It Wasn't the Square Windows - The Crashes of the de Havilland Comet
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- čas přidán 15. 12. 2023
- You have seen the documentaries. You have seen the CZcams videos. Everyone knows the square windows caused the breakups of the de Havilland Comet, except they didn't.
When I first uploaded this video in August of 2019, there were no videos on CZcams covering modern analysis of the crashes of the de Havilland Comet. Every documentary and CZcams video about the de Havilland Comet blamed the square windows. However, a little research shows that modern analysis disputes this.
Here are the links to the references in the video:
www.faa.gov/lessons_learned/t...
vietnamwcm.files.wordpress.co...
Petter Hörnfeldt (Mentour Pilot) has recently posted a video also explaining the real reason for the de Havilland Comet's crashes: Mentour Now! - YOU have Misunderstood The De Havilland Comet. It Wasn’t the Windows! • YOU have Misunderstood... - Věda a technologie
As a child I flew on the Comet from London to Singapore and back to see my family for summer holidays. It was pure luxury after supercharged piston planes like the Constellation and Super G Constellation. It took 2.5 days and nights on those and it took a week to recover from the noise and vibration. Then came the whispering giant, the Bristol Britannia. It was big and roomy and the turboprop engines so much smoother. Journey time cut to just about 2 days and nights. Then I flew the Comet. It was so fast and quiet. I was lucky. My father’s boss in Malaya lost his son on the one that went down. RIP.
Glad you made retirement
😊
@@thomasauslander3757
De Havilland (Of England) Comets were not grounded after 1970 due to structural problems.
*_It's interesting that some of the aircraft on the list should really have been noticeably safer than the Comet due to being a similar type but of much later design & manufacture but they definately were not safer._*
How things were back then -
*_Accident losses - % of aircraft built._*
DeHavilland Comet 4 UK 14%
DeHavilland Comet all mks 17%
Vickers VC10 UK 5%
*_The DH Comet had better safety than or similar safety to many other commercial passenger aircraft of a similar era_*
Douglas DC-1 99%
Douglas DC-2 47%
Douglas DC-3 30%
Douglas DC-4 26%
Boeing s300 72%
Boeing 307 70%
Boeing 247 48%
Boeing 707 20%
Lockheed L-049/149 Constellation 30%
Lockheed Electra Turboprop 29%
Fairchild FH-227 30%
McDonnell Douglas DC-8 14%
Sud Aviation Caravelle 15%
Canadair CL-44 Turboprop 46%
Convair CV-580 Turboprop 22%
A comparison of more recent aircraft.
Accident losses comparison examples.
1970s - 1980s
% of total Aircraft built
Similar aircraft type, date / decade, useage, size.
Biz Jets
BAe-125-800 1.7 %
Beechcraft Beechjet 400 2.2 %
Cessna 550 Citation II 7.1 %
Learjet 35 / 36 12 %
Beechcraft 1900 6%
Dassault Falcon 10 11.5%
Aérospatiale SN.601 22.5%
Medium size jets / Turboprops.
BAe-146 5.1%
Fokker 100 6%
McDonnell Douglas DC-9-30 9.5%
Fairchild FH-227 30%
McDonnell Douglas DC-8 14%
Canadair CL-44 Turboprop 46%
Convair CV-580 Turboprop 22%
Beechcraft, Fokker, McDonnell Douglass, Learjet, Fairchild, Aerospatiale, Canadair, Convair companies defunct.
All Comets, including some Comet 1s, had full civilian use certification at some point after 1954, civilian use certification only being withdrawn after commercial flying stopped. Examples were flying until 1997 - one example did a signals research global circumnavigation flight series in 1993 via Australia virtually without a rest travelling 28000 miles, only had an ice warning indicator issue during the flights.
*The DH Comet - World Firsts.*
1st gas turbine jet powered airliner. 1st high altitude 8psi pressurised full fuselage length passenger cabin airliner, not a trivial feature as structure strength required for pressurisation considerably exceeded strength required for normal flying stress. Nobody else had done anything similar before the Comet.
The b-47 used 2 relatively small, heavily built pressurised modules (the aircraft where 6 had their wings fold up in 2 months while flying & some had their wings fall off while parked).
The 1937 Boeing piston engined airliner pressurised passenger cabin was pressurised to 2 psi only - in fact that could easily be done as the normal unpressurized fuselage cabin structure strength for flying stresses only was all that was needed to be adequate so no significant weight increase issues needed addressing.
1st all hydraulically powered flying surface controls & actuators airliner with under carriage wheel disk brakes + ABS.
1st jet airliner to cross the Atlantic.
1st jet aircraft to do a world circumnavigation flights series.
*Of course De Havilland had prior experience building many all metal construction airframe aircraft including thousands of jet powered fighter aircraft that were primarily of metal construction with pressurised cockpits & jet engines built by De-Havilland & we know the world's first all metal construction airframe airliner was built in England in the 1920s by Handley Page.*
*_De Havilland did indeed always work to better than industry standards at the time, used up to date knowledge for the design & no evidence of negligence or criminal negligence was ever produced in relation to the DH Comet._*
The course of De Havilland & the general UK aerospace industry sector was not affected even slightly by the DH Comet.
*_Other interesting World firsts_*
_World's first turboprop aircraft._
*Vickers Viscount Turboprop Airliner 1947.*
*A 1945 Gloster Meteor Aircraft with Turboprop Gas Turbine Engine.*
👍 & 🙂 & of course 😎 indeed.
*C H E E R S* & without doubt -
_Toodle_ -PIP- *Old* *_Chap._*
. .... . ... . ... .. ... .... ... ....
Ivcxivcxivcxcxiivxvivcxiccxxcc
Interestingly, Neville Shute wrote "No Highway" in 1948 about a new aircraft mysteriously crashing (and the reluctant hero accidentally finds himself on an at-risk plane) due to metal fatigue.
And this is why we have 2 ground test airframes...the CAST (Complete Airframe Static test ) and the DADT (Damage and Durability Test )
Airframe fatigue testing was still in it's infancy during the Comet years. In the 70's, 80's & 90's my father worked for many years in an airframe materials (& fatigue) testing laboratory. Indeed he once explained (and showed) to me that for the majority of fatigue cracks they found during testing of the many different parts, rivet & screw holes were the most likely place for fatigue cracks to start. Interestingly, once a fatigue crack has started you can actually halt its further progress by drilling a hole through the end of the crack.
They also did much testing on adhesives and glued airframe construction, as well as on composite materials. Adhesives weakness were found to be peeling forces much more so than shear stress forces.
Once the airframe (or part) had successfully withstood the required number of flight simulations in order to receive an airworthiness certification, a final residual strength test was then done in which they stressed the airframe (or part) to the point of destruction. This final residual strength test also needed to pass a certain minimum requirement.
That's not true, fatigue testing in pressurized cabins was well-known and understood by the 1950s, the truth is de Havilland lacking in experience with the design of metal aircraft and pressurized cabins made very high risk decisions and many egregious errors that could have been prevented if de Havilland had simply followed industry standards at the time.
The truth is de Havilland was decades behind in aircraft technology and was still building aircraft primarily from wood and linen fabric... obsolete WW1 technology.
@@sandervanderkammen9230 That was my point; as far as I am aware the pioneering research done in airframe fatigue testing was by Arthur Wills of the Aeronautical Research Laboratory in 1947, presenting the results in 1949. Fatigue testing on the Comet started in 1949 under regulations set by the Air Registration Board, which were continuously being revised following research done by the RAF, with updated standards adopted by the ARB in 1953. De Havilland were following the industry standards at the time, but with fatigue testing of pressurised airframes being a very young area of research, these standards were continuously being revised.
@maidsandmuses *Junkers and Boeing were the world's leaders in pressurized aircraft and both conducted exhaustive research, development, and successful mass production during the 1930s, as did Douglas and Lockheed.*
*The Royal Aircraft Establishment and de Havilland received technical data on metal fatigue in pressurized cabins from the Boeing B-29 program during WW2.*
*Boeing by 1950 had produced over 5,000 aircraft with pressurized cabins, while de Havilland was still building aircraft primarily from wood and linen fabric when the Comet was in development.*
*The Comet Disaster is conclusive evidence that de Havilland simply lacked the required experience and technology to produce a large all-metal pressurized aircraft made from riveted aluminum alloys.*
@@sandervanderkammen9230
Kharzeestan Krappenz DiktorBummer Jurkzxoffenz etc and co - they should all note good with much awestruckness & extreme wonderment.
*UPDATE MORE BREAKING NEWS ETC*
De Havilland (Of England) Comets were not grounded after 1970 due to structural problems.
*_It's interesting that some of the aircraft on the list should really have been noticeably safer than the Comet due to being a similar type but of much later design & manufacture but they definately were not safer._*
How things were back then -
*_Accident losses - % of aircraft built._*
DeHavilland Comet 4 UK 14%
DeHavilland Comet all mks 17%
Vickers VC10 UK 5%
*_The DH Comet had better safety than or similar safety to many other commercial passenger aircraft of a similar era_*
Douglas DC-1 99%
Douglas DC-2 47%
Douglas DC-3 30%
Douglas DC-4 26%
Boeing s300 72%
Boeing 307 70%
Boeing 247 48%
Boeing 707 20%
Lockheed L-049/149 Constellation 30%
Lockheed Electra Turboprop 29%
Fairchild FH-227 30%
McDonnell Douglas DC-8 14%
Sud Aviation Caravelle 15%
Canadair CL-44 Turboprop 46%
Convair CV-580 Turboprop 22%
A comparison of more recent aircraft.
Accident losses comparison examples.
1970s - 1980s
% of total Aircraft built
Similar aircraft type, date / decade, useage, size.
Biz Jets
BAe-125-800 1.7 %
Beechcraft Beechjet 400 2.2 %
Cessna 550 Citation II 7.1 %
Learjet 35 / 36 12 %
Beechcraft 1900 6%
Dassault Falcon 10 11.5%
Aérospatiale SN.601 22.5%
Medium size jets / Turboprops.
BAe-146 5.1%
Fokker 100 6%
McDonnell Douglas DC-9-30 9.5%
Fairchild FH-227 30%
McDonnell Douglas DC-8 14%
Canadair CL-44 Turboprop 46%
Convair CV-580 Turboprop 22%
Beechcraft, Fokker, McDonnell Douglass, Learjet, Fairchild, Aerospatiale, Canadair, Convair companies defunct.
All Comets, including some Comet 1s, had full civilian use certification at some point after 1954, civilian use certification only being withdrawn after commercial flying stopped. Examples were flying until 1997 - one example did a signals research global circumnavigation flight series in 1993 via Australia virtually without a rest travelling 28000 miles, only had an ice warning indicator issue during the flights.
*The DH Comet - World Firsts.*
1st gas turbine jet powered airliner. 1st high altitude 8psi pressurised full fuselage length passenger cabin airliner, not a trivial feature as structure strength required for pressurisation considerably exceeded strength required for normal flying stress. Nobody else had done anything similar before the Comet.
The b-47 used 2 relatively small, heavily built pressurised modules (the aircraft where 6 had their wings fold up in 2 months while flying & some had their wings fall off while parked).
The 1937 Boeing piston engined airliner pressurised passenger cabin was pressurised to 2 psi only - in fact that could easily be done as the normal unpressurized fuselage cabin structure strength for flying stresses only was all that was needed to be adequate so no significant weight increase issues needed addressing.
1st all hydraulically powered flying surface controls & actuators airliner with under carriage wheel disk brakes + ABS.
1st jet airliner to cross the Atlantic.
1st jet aircraft to do a world circumnavigation flights series.
*Of course De Havilland had prior experience building many all metal construction airframe aircraft including thousands of jet powered fighter aircraft that were primarily of metal construction with pressurised cockpits & jet engines built by De-Havilland & we know the world's first all metal construction airframe airliner was built in England in the 1920s by Handley Page.*
*_De Havilland did indeed always work to better than industry standards at the time, used up to date knowledge for the design & no evidence of negligence or criminal negligence was ever produced in relation to the DH Comet._*
The course of De Havilland & the general UK aerospace industry sector was not affected even slightly by the DH Comet.
*_Other interesting World firsts_*
_World's first turboprop aircraft._
*Vickers Viscount Turboprop Airliner 1947.*
*A 1945 Gloster Meteor Aircraft with Turboprop Gas Turbine Engine.*
They might like to answer these questions.
*Which airline has just ordered*
*60 RR England Trent XWB Engines*
*& What aircraft are the engines for?*
_Bonus question for 10 points._
Which country has the
*World's Highest Combined Per Capita*
*Nuclear + Defence + Aerospace Sector Activity?*
👍 & 🙂 & of course 😎 indeed.
*C H E E R S* & without doubt -
_Toodle_ -PIP- *Old* *_Chap._*
. .... . ... . ... .. ... .... . ....... ... ....
Ivcxivcxivcxcxiivxvcvcvcivcxiccxxcc
Why
So.... it wasn't the square windows. It was metal fatigue caused by square windows. 😠 So, it was square windows. Got it.
I have a book written by the investigater. It was the windows. He was due to fly back to Britain in a Comet for the investigation. He rebooked the flight!
Metal fatigue caused by aluminum skins that were too thin and brittle, de Havilland Comet lacked several simple construction details that were already common practice in pressurized cabins
Yep. The rivet lines failed at the corners. The failure was caused by high stress at the window corners. The stresses were high because the window corners were squarish, and the added stress from riveting didn't help. The bonding method would probably have not resulted in failures. It was the two issues interacting. But, yes, the title of the video is misleading / clickbaity just like every other youtube video.
@@major__kong Wreckage recovered from the sea confirmed that the passenger windows were not involved in the catastrophic in-flight structural failures.
The Square windows theory has been completely debunked as a red herring, a total fabrication concocted by de Havilland long before the actual cause was found.
The entire structure of the Comet was inadequate, poorly designed and constructed with aluminum skins that were too thin and made from an alloy (AL2014B) that was too brittle, the Comet lacked proper Rip-stop doubler joints and the fuselage frame hoops were too narrow and spaced to far apart to prevent cracks from joining up with adjacent panels.
de Havilland used an extremely crude and unreliable method of installing riveted fasteners and its quality control standards were very poor.
@@WilhelmKarsten The pictures I'm looking at in the video show rivet line tearing near the window corners. Like I said, it was a combination of things, some of which you mentioned.
Enjoyed your video immensely, thank you.There can't ever be enough aircraft channels on Ytube, I'm sure.Welcome,good sir,I look forward to your future content.
*Krapper & co 😅😅😅👍🇮🇪*
🇨🇳 Have they had chicken chow mein for dinner today🇨🇳?
*They might like to try reading the questions & attempt a coherent reply in glorious victorious ENGLISH. THE WORLDS MOST WIDELY SPOKEN VICTORIOUS GLoRIOUS PEOPLE'S INTERNATIONAL LANGUAGE & THE MANDATORY VICTORIOUS GLoRIOUS PEOPLE'S COMMERCIAL AVIATION LANGUAGE.*
*Wrong Answer.*
They might like to memorize.
*_More than 33,000 Whittle style centrifugal compressor internal combustion gas turbine aircraft engines have been produced, from the time Whittle demonstrated his aircraft engine for the first time in the world, to the present date._*
*How many fixed wing & rotating wing aircraft types have used the Whittle Gas turbine aircraft engine including reverse flow combuster type engines?*
Also, if they would like to discuss inventions, the gas turbine was invented in the people's republic of glorious England before the 1800s. Which glorious & infinitely superior & always victorious English person invented the gas turbine engine before 1800?
*_DON'T TRY INTIMATING ME SONNY?_*
*JUST THE FAX HERE BOY*
@@Paul-Nicer58Just answer the question *Please name a single British company that still makes British jet aircraft in the UK???*
Chow Mein gobblers should be aware.
*_Accident losses - % of aircraft built._*
DeHavilland Comet 4 UK 14%
DeHavilland Comet all mks 17%
Vickers VC10 UK 5%
Boeing 707 USA *20%*
Lockheed Electra USA *29%*
Chow Mein gobblers should be aware.
*_Accident losses - % of aircraft built._*
DeHavilland Comet 4 UK 14%
DeHavilland Comet all mks 17%
Vickers VC10 UK 5%
Boeing 707 USA *20%*
Lockheed Electra USA *29%*
😂😂😂😂😂
Great video. Thanks for this video uploader. ☺️
This is an outstanding and throroughly researched video documentary on the failure of the de Havilland Comet. Most of the others found on CZcams are far less rigorous and, in many instances, erroneous.
@sandervanderkammen9230
*UPDATE MORE BREAKING NEWS ETC*
De Havilland (Of England) Comets / Nimrods were not grounded after 1970 due to structural problems.
Of course it should indeed be noted that as far as flying stresses are concerned the Comet & Nimrod had particularly robust airframes.
*_It's interesting that some of the aircraft on the list should really have been noticeably safer than the Comet due to being a similar type but of much later design & manufacture but they definately were not safer._*
How things were back then -
*_Accident losses - % of aircraft built._*
DeHavilland Comet 4 UK 14%
DeHavilland Comet all mks 17%
Vickers VC10 UK 5%
*_The DH Comet had better safety than or similar safety to many other commercial passenger aircraft of a similar era_*
Douglas DC-1 99%
Douglas DC-2 47%
Douglas DC-3 30%
Douglas DC-4 26%
Boeing s300 72%
Boeing 307 70%
Boeing 247 48%
Boeing 707 20%
Lockheed L-049/149 Constellation 30%
Lockheed Electra Turboprop 29%
Fairchild FH-227 30%
McDonnell Douglas DC-8 14%
Sud Aviation Caravelle 15%
Canadair CL-44 Turboprop 46%
Convair CV-580 Turboprop 22%
A comparison of more recent aircraft.
Accident losses comparison examples.
1970s - 1980s
% of total Aircraft built
Similar aircraft type, date / decade, useage, size.
Biz Jets
BAe-125-800 1.7 %
Beechcraft Beechjet 400 2.2 %
Cessna 550 Citation II 7.1 %
Learjet 35 / 36 12 %
Beechcraft 1900 6%
Dassault Falcon 10 11.5%
Aérospatiale SN.601 22.5%
Medium size jets / Turboprops.
BAe-146 5.1%
Fokker 100 6%
McDonnell Douglas DC-9-30 9.5%
Fairchild FH-227 30%
McDonnell Douglas DC-8 14%
Canadair CL-44 Turboprop 46%
Convair CV-580 Turboprop 22%
Beechcraft, Fokker, McDonnell Douglass, Learjet, Fairchild, Aerospatiale, Canadair, Convair companies defunct.
All Comets, including some Comet 1s, had full civilian use certification at some point after 1954, civilian use certification only being withdrawn after commercial flying stopped. Examples were flying until 1997 - one example did a signals research global circumnavigation flight series in 1993 via Australia virtually without a rest travelling 28000 miles, only had an ice warning indicator issue during the flights.
*The DH Comet - World Firsts.*
1st gas turbine jet powered airliner. 1st high altitude 8psi pressurised full fuselage length passenger cabin airliner, not a trivial feature as structure strength required for pressurisation considerably exceeded strength required for normal flying stress. Nobody else had done anything similar before the Comet.
The b-47 used 2 relatively small, heavily built pressurised modules (the aircraft where 6 had their wings fold up in 2 months while flying & some had their wings fall off while parked).
The 1937 Boeing piston engined airliner pressurised passenger cabin was pressurised to 2 psi only - in fact that could easily be done as the normal unpressurized fuselage cabin structure strength for flying stresses only was all that was needed to be adequate so no significant weight increase issues needed addressing.
1st all hydraulically powered flying surface controls & actuators airliner with under carriage wheel disk brakes + ABS.
1st jet airliner to cross the Atlantic.
1st jet aircraft to do a world circumnavigation flights series.
*Of course De Havilland had prior experience building many all metal construction airframe aircraft including thousands of jet powered fighter aircraft that were primarily of metal construction with pressurised cockpits & jet engines built by De-Havilland & we know the world's first all metal construction airframe airliner was built in England in the 1920s by Handley Page.*
*_De Havilland did indeed always work to better than industry standards at the time, used up to date knowledge for the design & no evidence of negligence or criminal negligence was ever produced in relation to the DH Comet._*
The course of De Havilland & the general UK aerospace industry sector was not affected even slightly by the DH Comet.
*_Other interesting World firsts_*
_World's first turboprop aircraft._
*Vickers Viscount Turboprop Airliner 1947.*
*A 1945 Gloster Meteor Aircraft with Turboprop Gas Turbine Engine.*
People might like to have a go at these questions.
*Which airline has just ordered*
*60 RR England Trent XWB Engines*
*& What aircraft are the engines for?*
_Bonus question for 10 points._
Which country has the
*World's Highest Combined Per Capita*
*Nuclear + Defence + Aerospace Sector Activity?*
👍 & 🙂 & of course 😎 indeed.
Cheers.
_Toodle_ -PIP- *Old* *_Chaps / Chapesses._*
.....
. .... . ... . ... ..
... .... ... ....
Ivcxivcxiv
cxcxii
vxvivcxic
cxxcc
I pointed this out recently to another YT and received only derision. Glad you are reinforcing the real facts.
me too,,, people forget cockpit windows are square,,, its not as simple as that but access panels are or can be square doors are oblong,, the structure can take it if designed right
Most of what you see or read in the media about the Comet Disaster is based on a theory presented by de Havilland long before the true cause of the catastrophic in-flight structural failures was revealed.
de Havilland used aluminum skins that were too thin and brittle.
They didn't properly overlap the sheets and the frames were not strong enough to prevent cracks from joining up with adjacent panels.
These were all very basic engineering mistakes made because d-H had little experience in building aircraft from riveted aluminum, they were still building jet aircraft fuselages primarily from wood and fabric.
@@sandervanderkammen9230 They used bonding, not riveting.
@Swaggerlot *That's completely false, the Comet Disaster was caused by bad design and construction of riveted aluminum alloy airframes.*
@@sandervanderkammen9230 Redux bonding was used extensively to attach skins to stringers rather than rivets.
Great video. I wasn’t aware of this, thanks for the great summary of the facts.
Chicken Chow Mein Munchers should be aware.
*_Accident losses - % of aircraft built._*
DeHavilland Comet 4 UK 14%
DeHavilland Comet all mks 17%
Vickers VC10 UK 5%
Boeing 707 USA *20%*
Lockheed Electra USA *29%*
Chow Mein gobblers should be aware.
*_Accident losses - % of aircraft built._*
DeHavilland Comet 4 UK 14%
DeHavilland Comet all mks 17%
Vickers VC10 UK 5%
Boeing 707 USA *20%*
Lockheed Electra USA *29%*
Chow Mein gobblers should be aware.
*_Accident losses - % of aircraft built._*
DeHavilland Comet 4 UK 14%
DeHavilland Comet all mks 17%
Vickers VC10 UK 5%
Boeing 707 USA *20%*
Lockheed Electra USA *29%*
Chow Mein gobblers should be aware.
*_Accident losses - % of aircraft built._*
DeHavilland Comet 4 UK 14%
DeHavilland Comet all mks 17%
Vickers VC10 UK 5%
Boeing 707 USA *20%*
Lockheed Electra USA *29%*
Age 6 or 7 I flew from Nicosia Cyprus to England and back again with my parents in about 1961 or 1962 in a Comet 4B. We stopped in Athens (Ellinikon, old airport) Looking down on Athens as the sun rose is etched into my memory, as was looking down on the snow of the Swiss Alps in bright sunshine. Very memorable. The aircraft was very comfortable as I remember.
Your very lucky to still be alive... the Comet is the most dangerous jet airliner in history.
@@WilhelmKarsten
@sandervanderkammen9230
Kharzeestan Krappenz DiktorBummer Jurkzxoffenz etc and co - they should all note good with much awestruckness & extreme wonderment.
*UPDATE MORE BREAKING NEWS ETC*
De Havilland (Of England) Comets were not grounded after 1970 due to structural problems.
*_It's interesting that some of the aircraft on the list should really have been noticeably safer than the Comet due to being a similar type but of much later design & manufacture but they definately were not safer._*
How things were back then -
*_Accident losses - % of aircraft built._*
DeHavilland Comet 4 UK 14%
DeHavilland Comet all mks 17%
Vickers VC10 UK 5%
*_The DH Comet had better safety than or similar safety to many other commercial passenger aircraft of a similar era_*
Douglas DC-1 99%
Douglas DC-2 47%
Douglas DC-3 30%
Douglas DC-4 26%
Boeing s300 72%
Boeing 307 70%
Boeing 247 48%
Boeing 707 20%
Lockheed L-049/149 Constellation 30%
Lockheed Electra Turboprop 29%
Fairchild FH-227 30%
McDonnell Douglas DC-8 14%
Sud Aviation Caravelle 15%
Canadair CL-44 Turboprop 46%
Convair CV-580 Turboprop 22%
A comparison of more recent aircraft.
Accident losses comparison examples.
1970s - 1980s
% of total Aircraft built
Similar aircraft type, date / decade, useage, size.
Biz Jets
BAe-125-800 1.7 %
Beechcraft Beechjet 400 2.2 %
Cessna 550 Citation II 7.1 %
Learjet 35 / 36 12 %
Beechcraft 1900 6%
Dassault Falcon 10 11.5%
Aérospatiale SN.601 22.5%
Medium size jets / Turboprops.
BAe-146 5.1%
Fokker 100 6%
McDonnell Douglas DC-9-30 9.5%
Fairchild FH-227 30%
McDonnell Douglas DC-8 14%
Canadair CL-44 Turboprop 46%
Convair CV-580 Turboprop 22%
Beechcraft, Fokker, McDonnell Douglass, Learjet, Fairchild, Aerospatiale, Canadair, Convair companies defunct.
All Comets, including some Comet 1s, had full civilian use certification at some point after 1954, civilian use certification only being withdrawn after commercial flying stopped. Examples were flying until 1997 - one example did a signals research global circumnavigation flight series in 1993 via Australia virtually without a rest travelling 28000 miles, only had an ice warning indicator issue during the flights.
*The DH Comet - World Firsts.*
1st gas turbine jet powered airliner. 1st high altitude 8psi pressurised full fuselage length passenger cabin airliner, not a trivial feature as structure strength required for pressurisation considerably exceeded strength required for normal flying stress. Nobody else had done anything similar before the Comet.
The b-47 used 2 relatively small, heavily built pressurised modules (the aircraft where 6 had their wings fold up in 2 months while flying & some had their wings fall off while parked).
The 1937 Boeing piston engined airliner pressurised passenger cabin was pressurised to 2 psi only - in fact that could easily be done as the normal unpressurized fuselage cabin structure strength for flying stresses only was all that was needed to be adequate so no significant weight increase issues needed addressing.
1st all hydraulically powered flying surface controls & actuators airliner with under carriage wheel disk brakes + ABS.
1st jet airliner to cross the Atlantic.
1st jet aircraft to do a world circumnavigation flights series.
*Of course De Havilland had prior experience building many all metal construction airframe aircraft including thousands of jet powered fighter aircraft that were primarily of metal construction with pressurised cockpits & jet engines built by De-Havilland & we know the world's first all metal construction airframe airliner was built in England in the 1920s by Handley Page.*
*_De Havilland did indeed always work to better than industry standards at the time, used up to date knowledge for the design & no evidence of negligence or criminal negligence was ever produced in relation to the DH Comet._*
The course of De Havilland & the general UK aerospace industry sector was not affected even slightly by the DH Comet.
*_Other interesting World firsts_*
_World's first turboprop aircraft._
*Vickers Viscount Turboprop Airliner 1947.*
*A 1945 Gloster Meteor Aircraft with Turboprop Gas Turbine Engine.*
They might like to answer these questions.
*Which airline has just ordered*
*60 RR England Trent XWB Engines*
*& What aircraft are the engines for?*
_Bonus question for 10 points._
Which country has the
*World's Highest Combined Per Capita*
*Nuclear + Defence + Aerospace Sector Activity?*
👍 & 🙂 & of course 😎 indeed.
Cheers.
_Toodle_ -PIP- *Old* *_Chap._*
. .... . ... . .
.. .. ... .... ... ....
Ivcxivcxivcxcxiiv
xvivcxiccxxcc
Excellent analysis!
*UPDATE MORE BREAKING NEWS ETC*
De Havilland (Of England) Comets / Nimrods were not grounded after 1970 due to structural problems.
Of course it should indeed be noted that as far as flying stresses are concerned the Comet & Nimrod had particularly robust airframes.
*_It's interesting that some of the aircraft on the list should really have been noticeably safer than the Comet due to being a similar type but of much later design & manufacture but they definately were not safer._*
How things were back then -
*_Accident losses - % of aircraft built._*
DeHavilland Comet 4 UK 14%
DeHavilland Comet all mks 17%
Vickers VC10 UK 5%
*_The DH Comet had better safety than or similar safety to many other commercial passenger aircraft of a similar era_*
Douglas DC-1 99%
Douglas DC-2 47%
Douglas DC-3 30%
Douglas DC-4 26%
Boeing s300 72%
Boeing 307 70%
Boeing 247 48%
Boeing 707 20%
Lockheed L-049/149 Constellation 30%
Lockheed Electra Turboprop 29%
Fairchild FH-227 30%
McDonnell Douglas DC-8 14%
Sud Aviation Caravelle 15%
Canadair CL-44 Turboprop 46%
Convair CV-580 Turboprop 22%
A comparison of more recent aircraft.
Accident losses comparison examples.
1970s - 1980s
% of total Aircraft built
Similar aircraft type, date / decade, useage, size.
Biz Jets
BAe-125-800 1.7 %
Beechcraft Beechjet 400 2.2 %
Cessna 550 Citation II 7.1 %
Learjet 35 / 36 12 %
Beechcraft 1900 6%
Dassault Falcon 10 11.5%
Aérospatiale SN.601 22.5%
Medium size jets / Turboprops.
BAe-146 5.1%
Fokker 100 6%
McDonnell Douglas DC-9-30 9.5%
Fairchild FH-227 30%
McDonnell Douglas DC-8 14%
Canadair CL-44 Turboprop 46%
Convair CV-580 Turboprop 22%
Beechcraft, Fokker, McDonnell Douglass, Learjet, Fairchild, Aerospatiale, Canadair, Convair companies defunct.
All Comets, including some Comet 1s, had full civilian use certification at some point after 1954, civilian use certification only being withdrawn after commercial flying stopped. Examples were flying until 1997 - one example did a signals research global circumnavigation flight series in 1993 via Australia virtually without a rest travelling 28000 miles, only had an ice warning indicator issue during the flights.
*The DH Comet - World Firsts.*
1st gas turbine jet powered airliner. 1st high altitude 8psi pressurised full fuselage length passenger cabin airliner, not a trivial feature as structure strength required for pressurisation considerably exceeded strength required for normal flying stress. Nobody else had done anything similar before the Comet.
The b-47 used 2 relatively small, heavily built pressurised modules (the aircraft where 6 had their wings fold up in 2 months while flying & some had their wings fall off while parked).
The 1937 Boeing piston engined airliner pressurised passenger cabin was pressurised to 2 psi only - in fact that could easily be done as the normal unpressurized fuselage cabin structure strength for flying stresses only was all that was needed to be adequate so no significant weight increase issues needed addressing.
1st all hydraulically powered flying surface controls & actuators airliner with under carriage wheel disk brakes + ABS.
1st jet airliner to cross the Atlantic.
1st jet aircraft to do a world circumnavigation flights series.
*Of course De Havilland had prior experience building many all metal construction airframe aircraft including thousands of jet powered fighter aircraft that were primarily of metal construction with pressurised cockpits & jet engines built by De-Havilland & we know the world's first all metal construction airframe airliner was built in England in the 1920s by Handley Page.*
*_De Havilland did indeed always work to better than industry standards at the time, used up to date knowledge for the design & no evidence of negligence or criminal negligence was ever produced in relation to the DH Comet._*
The course of De Havilland & the general UK aerospace industry sector was not affected even slightly by the DH Comet.
*_Other interesting World firsts_*
_World's first turboprop aircraft._
*Vickers Viscount Turboprop Airliner 1947.*
*A 1945 Gloster Meteor Aircraft with Turboprop Gas Turbine Engine.*
People might like to have a go at these questions.
*Which airline has just ordered*
*60 RR England Trent XWB Engines*
*& What aircraft are the engines for?*
_Bonus question for 10 points._
Which country has the
*World's Highest Combined Per Capita*
*Nuclear + Defence + Aerospace Sector Activity?*
👍 & 🙂 & of course 😎 indeed.
Cheers.
_Toodle_ -PIP- *Old* *_Chaps / Chapesses._*
. .... . ... . ... ..
... .... ... ....
Ivcxivcxivcxcxii
vxvivcxiccxxcc
Personally I think this is one of the most beautiful aircraft ever made.
Yes, it was.
It was also the worst engineering failure in commercial aviation history, 492 people killed out of pure incompetence and criminal negligence.
A truly shameful and humiliating chapter in British aviation history
@@Woffy. Sorry lad, Boeing built the first pressurized airliner and Germany built first pressurized aircraft and the first pressurized jet.
The Boeing B-47 flew higher, faster and with a higher cabin pressure differential 2 years earlier.
de Havilland and the Royal Aircraft Establishment received technical data on metal fatigue in pressurized cabins from the B-29 program during WW2.
The Junkers Ju-86 was flying pressurized to over 52,000 feet during WW2.
By 1949 Boeing had manufactured 5,000 pressurized aircraft.
The Boeing Jet Stratoliner first flew on July 15th 1954, before anyone (including de Havilland) knew what caused the catastrophic in-flight structural failures of the Comet Disaster.
Thank you for the correction, no it was not the first my error. I think I was triggered by your comment 'It was the worst ... etc. Yes it was bad but not the worst. I was not including military airframes which were built like brick shithouses. @@WilhelmKarsten
@@Woffy. No worries, it happens.
The de Haviland Comet does indeed have the highest loss rate and fatalities statistics of any jet airliner.
Comet 1 has a 46% loss rate and the highest fatalities statistics. The Comet 4 is a close 2nd place..
39 hull loss accidents and 492 deaths in just 1.7 million hours of total flight time...
You were over 1,000 times more likely to die on a Comet than a Boeing 737 Max.
The stress is on the outside (finger side) of your paper clamp, not the inside. I dont know how those cracks came to be there, but whatever put them there it was not repeated pressure from your fingers.
The video has quite a lot of tripe & pork included, not to be taken seriously.
@@Paul-mh9pr *Please name a single British company that still makes British jet aircraft in the UK???*
Chow Mein gobblers should be aware.
*_Accident losses - % of aircraft built._*
DeHavilland Comet 4 UK 14%
DeHavilland Comet all mks 17%
Vickers VC10 UK 5%
Boeing 707 USA *20%*
Lockheed Electra USA *29%*
Chow Mein gobblers should be aware.
*_Accident losses - % of aircraft built._*
DeHavilland Comet 4 UK 14%
DeHavilland Comet all mks 17%
Vickers VC10 UK 5%
Boeing 707 USA *20%*
Lockheed Electra USA *29%*
😂😂😂😂😂😂😂😂
Thanks for a new slant for an old question. Probably
Neville shute, one of the design team of the project, back in the 60-70s wrote about the metal fatigue problems, in his autobiography," sliderule" can't quite recall details, but i think he was of the mind that, shape didnt really cause the metal fatigue but it was inherit in the design and the british he felt, unlike american co.s didn't have enough investment in design researching and engineering and new aviation advances.but thats the gist i think of what i recall reading then.
Metal fatigue was well-known and understood by the industry at the time... both the Royal Aircraft Establishment and de Havilland had received data on metal fatigue in pressurized cabins from the Boeing B-29 program during WW2.
But.. In some Discovery documentary i watched many years ago, it was said that the window frames were supposed to be glued but a production engineer was complaining for one of the managers -"we have to build fixtures and it is a lot of trouble, can't we simply use rivets instead?"
And according to that documentary, the manager said -"alright, use rivets"..
Maybe it's not a design flaw after all then
There have been a couple of British documentaries (with American language versions) that are appallingly bad, just absolute revisionist garbage.
The Comet Disaster is the worst engineering failure in commercial jet aviation history, the result of engineering incompetence and criminal negligence.
The aluminum skins on Comet were made too thin, (just 1mm)
And an alloy that was too brittle (AL2014B)
The Comet lacked proper rip-stop doubler joints, standard for pressurized cabins at the time.
And the fuselage reinforcement hoops were too weak and spaced too far apart to prevent cracks from joining up with adjacent panels.
The Comet also had other fatal flaws the de Havilland attempted to cover-up, several runway excursions that were caused by a major design flaw in the engine inlets, and flight controls and flaps that were poorly designed and needed remedial engineering work to fix.
The tragedy of the Comet Disaster was that it could have been easily prevented if de Havilland had simply followed well-known and understood industry standards for construction of pressurized cabins made from riveted aluminum alloys.
@@sandervanderkammen9230
@sandervanderkammen9230
They might like to consider -
Comet Accident Losses Brief Comparison.
A brief comparison & view of how thing were then.
Accident Losses, % of total Aircraft built.
Lockheed Electra. USA. Turboprop.
29% Accident Losses
Vickers Viscount UK
29% Accident Losses
1st turboprop pressurised cabin metal airframe construction aircraft in the world. 10 years ahead of the Lockheed Electra.
Boeing 707 USA
20% Accident Losses
DeHavilland Comet all mks UK
17% Accident Losses
DeHavilland Comet 4 UK
14% Accident Losses
Vickers VC10 UK
A very popular aircraft with passengers,
BOAC continually lied about it being loss making in order to obtain govt subsidies.
5% Accident Losses & had a very good passenger crash survival rate for the period.
@@sandervanderkammen9230
*Krapper & co 😅😅😅👍🇮🇪*
🇨🇳 Have they had chicken chow mein for dinner today🇨🇳?
*They might like to try reading the questions & attempt a coherent reply in glorious victorious ENGLISH. THE WORLDS MOST WIDELY SPOKEN VICTORIOUS GLoRIOUS PEOPLE'S INTERNATIONAL LANGUAGE & THE MANDATORY VICTORIOUS GLoRIOUS PEOPLE'S COMMERCIAL AVIATION LANGUAGE.*
*Wrong Answer.*
They might like to memorize.
*_More than 33,000 Whittle style centrifugal compressor internal combustion gas turbine aircraft engines have been produced, from the time Whittle demonstrated his aircraft engine for the first time in the world, to the present date._*
*How many fixed wing & rotating wing aircraft types have used the Whittle Gas turbine aircraft engine including reverse flow combuster type engines?*
Also, if they would like to discuss inventions, the gas turbine was invented in the people's republic of glorious England before the 1800s. Which glorious & infinitely superior & always victorious English person invented the gas turbine engine before 1800?
*_DON'T TRY INTIMATING ME SONNY?_*
*JUST THE FAX HERE BOY*
@@sandervanderkammen9230
They can take notice.
*_Chicken Chow mein is nice?_*
Bs by the way, total 😂
No evidence of negligence or criminality or not working to better than industry standards exists.
*DH had built large numbers of metal construction airframe aircraft before the Comet.*
Comet all Mks loss rate 17%
*_Comet 4 loss rate 14%_*
Boeing 707 loss rate 20%
Lockheed Electra 29%
Vickers VC10 5%
@@Paul-Nicer58 *Please name a single British company that still makes British jet aircraft in the UK???*
When countersunk rivets were used in panels with thin outer skins the rivet holes had to be "dimpled" into a doubler strip under the skin (unlike your drawing at 9.32 to 9.35), the original process pressed the dimples into a former after the hole was drilled. Some of these dimples caused small cracks to spread out from the edge of the hole - crack starters! After the full Comet 1 crash investigation the process was changed for the Comet 4 and the dimples were produced by a spinning tool and the inspection for cracks was tightened right up.
But there were many other significant design changes on later Comets because the design stresses used for the original design were just too high. For example, the Comet 2 (only used by the RAF), in addition to having the square windows replaced by oval ones during production, had external doubler plates under the rear wing spars because without them the spars would have failed due to fatigue.
Chow Mein gobblers should be aware.
*_Accident losses - % of aircraft built._*
DeHavilland Comet 4 UK 14%
DeHavilland Comet all mks 17%
Vickers VC10 UK 5%
Boeing 707 USA *20%*
Lockheed Electra USA *29%*
Chow Mein gobblers should be aware.
*_Accident losses - % of aircraft built._*
DeHavilland Comet 4 UK 14%
DeHavilland Comet all mks 17%
Vickers VC10 UK 5%
Boeing 707 USA *20%*
Lockheed Electra USA *29%*
Chow Mein gobblers should be aware.
*_Accident losses - % of aircraft built._*
DeHavilland Comet 4 UK 14%
DeHavilland Comet all mks 17%
Vickers VC10 UK 5%
Boeing 707 USA *20%*
Lockheed Electra USA *29%*
😅😅😅😅
Surprising that your bag clip failed outwards! Was it pressurized??
The amazing bag clip disaster was something to do with the wonderful video author be blissfully unaware of some very important facts rather incredibly.
I worked in the stress office at Dehavilland (which had become HSA by the time I joined in 1974). The Departmental head was Ralph Hare at the time, he was ending his career as mine was starting . The window reinforcing doublers were designed to be Redux bonded but order books were full and Ralph was asked by Manufacturing Director if they could rivet them on which was quicker ( not cheaper). The idea that “square windows” caused the disasters has somehow become folklore but as clearly shown in your images window apertures were radiused in the corners to reduce stress concentrations. As you say the punched rivet holes introduced tiny micro cracks in the surface of the holes which propagated with cabin pressurisation/ depressurisation cycles. If a new test specimen had been used for the fatigue test then the true ( reduced) fatigue life would have been found but the test was done using the previously used ( and passed) cabin over pressure test specimen. As you say the cold working of the material around the crack tip increases the material strength and so although the micro cracks were present at the start of the fatigue test , the cracks developed much more slowly than they would have done on a fresh test specimen and gave a false outcome. It is important to know that the inquiry concluded DH were working at or beyond the current state of knowledge at the time and shows the hidden risks of being “the first” with new technology.
Ralph was a real Gent and all round top banana having been one of the original 9 members of the DH Mosquito design team. It was one of his biggest regrets that he had allowed Manufacturing to change to rivets. There was an interview on CZcams where he says this but not sure if its still on here.
Wreckage recovered from the sea confirmed that the passenger windows were not related in any way with the catastrophic in-flight structural failures.
The explosive cabin rupture was along the crown of the fuselage were de Havilland had used aluminum skins that were thinner than the rest of the pressure cabin.
AL2014B alloy is too brittle for the application and the Comet lacked proper rip-stop doubler joints and the fuselage reinforcement hoops were too weak and spaced too far apart to prevent cracks from joining up with adjacent panels.
The riveting techniques were also found to be well below industry standards for pressurized cabins and a disturbing number of manufacturing defects were found on completed aircraft that had completely eascaped QC inspection.
@@sandervanderkammen9230
@sandervanderkammen9230
Kharzeestan Krappenz DiktorBummer Jurkzxoffenz etc and co - they should all note good with much awestruckness & extreme wonderment.
*UPDATE MORE BREAKING NEWS ETC*
De Havilland (Of England) Comets were not grounded after 1970 due to structural problems.
*_It's interesting that some of the aircraft on the list should really have been noticeably safer than the Comet due to being a similar type but of much later design & manufacture but they definately were not safer._*
How things were back then -
*_Accident losses - % of aircraft built._*
DeHavilland Comet 4 UK 14%
DeHavilland Comet all mks 17%
Vickers VC10 UK 5%
*_The DH Comet had better safety than or similar safety to many other commercial passenger aircraft of a similar era_*
Douglas DC-1 99%
Douglas DC-2 47%
Douglas DC-3 30%
Douglas DC-4 26%
Boeing s300 72%
Boeing 307 70%
Boeing 247 48%
Boeing 707 20%
Lockheed L-049/149 Constellation 30%
Lockheed Electra Turboprop 29%
Fairchild FH-227 30%
McDonnell Douglas DC-8 14%
Sud Aviation Caravelle 15%
Canadair CL-44 Turboprop 46%
Convair CV-580 Turboprop 22%
A comparison of more recent aircraft.
Accident losses comparison examples.
1970s - 1980s
% of total Aircraft built
Similar aircraft type, date / decade, useage, size.
Biz Jets
BAe-125-800 1.7 %
Beechcraft Beechjet 400 2.2 %
Cessna 550 Citation II 7.1 %
Learjet 35 / 36 12 %
Beechcraft 1900 6%
Dassault Falcon 10 11.5%
Aérospatiale SN.601 22.5%
Medium size jets / Turboprops.
BAe-146 5.1%
Fokker 100 6%
McDonnell Douglas DC-9-30 9.5%
Fairchild FH-227 30%
McDonnell Douglas DC-8 14%
Canadair CL-44 Turboprop 46%
Convair CV-580 Turboprop 22%
Beechcraft, Fokker, McDonnell Douglass, Learjet, Fairchild, Aerospatiale, Canadair, Convair companies defunct.
All Comets, including some Comet 1s, had full civilian use certification at some point after 1954, civilian use certification only being withdrawn after commercial flying stopped. Examples were flying until 1997 - one example did a signals research global circumnavigation flight series in 1993 via Australia virtually without a rest travelling 28000 miles, only had an ice warning indicator issue during the flights.
*The DH Comet - World Firsts.*
1st gas turbine jet powered airliner. 1st high altitude 8psi pressurised full fuselage length passenger cabin airliner, not a trivial feature as structure strength required for pressurisation considerably exceeded strength required for normal flying stress. Nobody else had done anything similar before the Comet.
The b-47 used 2 relatively small, heavily built pressurised modules (the aircraft where 6 had their wings fold up in 2 months while flying & some had their wings fall off while parked).
The 1937 Boeing piston engined airliner pressurised passenger cabin was pressurised to 2 psi only - in fact that could easily be done as the normal unpressurized fuselage cabin structure strength for flying stresses only was all that was needed to be adequate so no significant weight increase issues needed addressing.
1st all hydraulically powered flying surface controls & actuators airliner with under carriage wheel disk brakes + ABS.
1st jet airliner to cross the Atlantic.
1st jet aircraft to do a world circumnavigation flights series.
*Of course De Havilland had prior experience building many all metal construction airframe aircraft including thousands of jet powered fighter aircraft that were primarily of metal construction with pressurised cockpits & jet engines built by De-Havilland & we know the world's first all metal construction airframe airliner was built in England in the 1920s by Handley Page.*
*_De Havilland did indeed always work to better than industry standards at the time, used up to date knowledge for the design & no evidence of negligence or criminal negligence was ever produced in relation to the DH Comet._*
The course of De Havilland & the general UK aerospace industry sector was not affected even slightly by the DH Comet.
*_Other interesting World firsts_*
_World's first turboprop aircraft._
*Vickers Viscount Turboprop Airliner 1947.*
*A 1945 Gloster Meteor Aircraft with Turboprop Gas Turbine Engine.*
They might like to answer these questions.
*Which airline has just ordered*
*60 RR England Trent XWB Engines*
*& What aircraft are the engines for?*
_Bonus question for 10 points._
Which country has the
*World's Highest Combined Per Capita*
*Nuclear + Defence + Aerospace Sector Activity?*
👍 & 🙂 & of course 😎 indeed.
Cheers.
_Toodle_ -PIP- *Old* *_Chap._*
. .... . ... . ... ..
... .... ... ....
Ivcxivcxivcxcx
iivxvivcxiccxxcc
@@sandervanderkammen9230
_"Wreckage recovered from the sea confirmed that the passenger windows were not related in any way with the catastrophic in-flight structural failures"???._
*The windows shape & anything to do with hatches, doors & windows is relevant of course. The fact that wreckage from one aircraft incident or the water tank test fuselage showed a particular fracture route doesn't definately allow a particular conclusion regarding the window shape one way or the other.*
_"The explosive cabin rupture was along the crown of the fuselage where de Havilland had used aluminum skins that were thinner than the rest of the pressure cabin"??_
*The fuselage crown skin thickness relative to the rest of the fuselage skin is irrelevant & was not a cause of any incidents.*
_"AL2014B alloy is too brittle for the application"???_
*The particular alloys used passed all De Havilland's tests, the alloy used became unavailable as improved alloys had been developed which had nothing to do with the Comet.*
_"The Comet lacked proper rip-stop doubler joints and the fuselage reinforcement hoops were too weak and spaced too far apart to prevent cracks from joining up with adjacent panels"?_
*Obviously rip stop doublers were used, frames (hoops) were not too weak & frames (hoops) were not spaced too far apart.*
_"The riveting techniques were also found to be well below industry standards for pressurized cabins"??_
*De Havilland had extensive experience with all metal airframe aircraft construction. A protracted and extensive testing programme involving fuselage tests & other assemblies & component testing showed riveting techniques used were acceptable.*
_"A disturbing number of manufacturing defects were found on completed aircraft that had completely escaped QC inspection"?_
*De Havilland had extensive prior experience with all metal airframe aircraft construction. A protracted and extensive testing programme involving fuselage tests & other testing showed riveting techniques used & manufacturing & QC methods & procedures were acceptable. It is not the case that a disturbing number of defects were found on completed aircraft that had completely escaped QC inspection.*
....... .. . .
xcvccxc
*C H E E R S.* 😎
@@petemaly8950 *Name a British jet aircraft still in production in the UK.???*
@@petemaly8950 *Name a British jet aircraft still in production in the UK.???*
That's very well explained and narrated. Thanks Bob!
It really were these crashes that broke the British aircraft industries back, which was a pity.
Both de Havilland and the entire British aircraft industry was already in steep decline after the devastation of WW2.
de Havilland was decades behind in aircraft technology and was still building aircraft primarily from wood and fabric well into the Jet Age.
@@Paul-mh9pr That's a completely false narrative, de Havilland was decades behind in aircraft technology and the Comet 1 was so badly designed that it's airworthiness certificate was permanently revoked.
The aircraft needed to be completely redesigned to be airworthy
@@Paul-mh9pr You are very, very confused and misinformed about the Comet Disaster.
Comet was the worst engineering failure in aviation history...the aircraft was so flawed and badly designed that even after several failed attempts to make the Comet 1 safe they could not meet certification requirements and the Comet 4 was a completely redesigned aircraft.
Comet 1 had its airworthiness certification permanently revoked
@@Paul-mh9pr de Havilland was a deeply troubled company that was still trying to build aircraft from wood and fabric well into the Jet Age...
Comet 1 wasn't even an all-metal design, Comet 1 still made extensive use of plywood in its construction... a hopelessly outdated and backwards design.
@@WilhelmKarsten
Wrong. You are presenting an entirely false picture.
The Comet simply attracted a lot of attention due to its highly advanced design & construction. DH was designing jet engine from first principles & building them.
DH used the most advanced design & construction techniques & processes anywhere in the world at the time.
The Comet was not built from plywood, chipboard & pva wood glue from the DIY store. In fact the highly advanced adhesives actually used are still currently manufactured & used in the aerospace industry today.
Changes made to the aircraft were simply mostly to look like something was being done &:most changes were changes that would have been actioned regardless & many changes were carried out just in case. The original design & construction were good. There were problems but at the time that was expected.
The most significant changes were more powerful engines & pointing the engine exhausts away from the fuselage.
There was never a complete redesign.
Fascinating and well described insight! Thank you.
Chow Mein gobblers should be aware.
*_Accident losses - % of aircraft built._*
DeHavilland Comet 4 UK 14%
DeHavilland Comet all mks 17%
Vickers VC10 UK 5%
Boeing 707 USA *20%*
Lockheed Electra USA *29%*
Chow Mein gobblers should be aware.
*_Accident losses - % of aircraft built._*
DeHavilland Comet 4 UK 14%
DeHavilland Comet all mks 17%
Vickers VC10 UK 5%
Boeing 707 USA *20%*
Lockheed Electra USA *29%*
Chow Mein gobblers should be aware.
*_Accident losses - % of aircraft built._*
DeHavilland Comet 4 UK 14%
DeHavilland Comet all mks 17%
Vickers VC10 UK 5%
Boeing 707 USA *20%*
Lockheed Electra USA *29%*
WELL DONE
You got it right, punched rivet holes and incorrect test procedure caused this.
Also the aluminum sheets on the roof were too thin and all were made from AL2014B an alloy so brittle it's not used anymore.
The Comet also lacked overlapping rip-stop doubler joints and the fuselage reinforcement hoops and stringers were too weak to prevent cracks from joining up with adjacent panels.
@@sandervanderkammen9230
_"Wreckage recovered from the sea confirmed that the passenger windows were not related in any way with the catastrophic in-flight structural failures"???._
*The windows shape & anything to do with hatches, doors & windows is relevant of course. The fact that wreckage from one aircraft incident or the water tank test fuselage showed a particular fracture route doesn't definately allow a particular conclusion regarding the window shape one way or the other.*
_"The explosive cabin rupture was along the crown of the fuselage where de Havilland had used aluminum skins that were thinner than the rest of the pressure cabin"??_
*The fuselage crown skin thickness relative to the rest of the fuselage skin is irrelevant & was not a cause of any incidents.*
_"AL2014B alloy is too brittle for the application"???_
*The particular alloys used passed all De Havilland's tests, the alloy used became unavailable as improved alloys had been developed which had nothing to do with the Comet.*
_"The Comet lacked proper rip-stop doubler joints and the fuselage reinforcement hoops were too weak and spaced too far apart to prevent cracks from joining up with adjacent panels"?_
*Obviously rip stop doublers were used, frames (hoops) were not too weak & frames (hoops) were not spaced too far apart.*
_"The riveting techniques were also found to be well below industry standards for pressurized cabins"??_
*De Havilland had extensive experience with all metal airframe aircraft construction. A protracted and extensive testing programme involving fuselage tests & other assemblies & component testing showed riveting techniques used were acceptable.*
_"A disturbing number of manufacturing defects were found on completed aircraft that had completely escaped QC inspection"?_
*De Havilland had extensive prior experience with all metal airframe aircraft construction. A protracted and extensive testing programme involving fuselage tests & other testing showed riveting techniques used & manufacturing & QC methods & procedures were acceptable. It is not the case that a disturbing number of defects were found on completed aircraft that had completely escaped QC inspection.*
Metal fatigue begins at the atomic level. Stress shears the atomic covalent bonds along a plane. The bonds reform at new shifted location when the stress removed. After sufficient stress cycles, the atomic dislocations coalesce into a microscopic crack. From new to failure, most of the fatigue life is at the atomic level, once a crack forms, failure is near.
This dislocation biz happens at stress levels significantly below the materials yield point.
DeHavilland’s initial testing procedure enhanced fatigue life by inducing beneficial residual stresses. These residual stresses must be overcome by applied stresses before the dislocations resume. Residual stress techniques (shot peening, ballizing) are common plane fabrication processes. Cheers
Chow Mein gobblers should be aware.
*_Accident losses - % of aircraft built._*
DeHavilland Comet 4 UK 14%
DeHavilland Comet all mks 17%
Vickers VC10 UK 5%
Boeing 707 USA *20%*
Lockheed Electra USA *29%*
Chow Mein gobblers should be aware.
*_Accident losses - % of aircraft built._*
DeHavilland Comet 4 UK 14%
DeHavilland Comet all mks 17%
Vickers VC10 UK 5%
Boeing 707 USA *20%*
Lockheed Electra USA *29%*
Chow Mein gobblers should be aware.
*_Accident losses - % of aircraft built._*
DeHavilland Comet 4 UK 14%
DeHavilland Comet all mks 17%
Vickers VC10 UK 5%
Boeing 707 USA *20%*
Lockheed Electra USA *29%*
*de Havilland Aircraft Company,*
*Our Motto:*
*_"50% isnt really that bad is it?"_*
Chow Mein gobblers should be aware.
*_Accident losses - % of aircraft built._*
DeHavilland Comet 4 UK 14%
DeHavilland Comet all mks 17%
Vickers VC10 UK 5%
Boeing 707 USA *20%*
Lockheed Electra USA *29%*
Why did you keep showing Comet 4s when it was the Comet 1 models that crashed?
There are very few photos of the Comet 1, half of them crashed in the first 2 years, the rest were chopped up and scrapped or modified into military transports.
I remember having seen a Nimrod on Air show in Berlin. It seems to be a military version of the Comet.
@engelbertkalkum8146 That's a common misconception that I once believed, the Hawker Siddeley H.S 801 Nimrod is actually a completely different aircraft, designed by a different company decades later and has no significant parts or sub-assemblies shared in common...
@@sandervanderkammen9230 Nimrod started as Comet 4C. The prototypes were even originally built as Comets. The rest was built new, and not modified passenger Comets, that is correct, but it was the same basic design. deHavilland became part of Hawker-Siddeley in 1959. (Later BAe)
@hepphepps8356 The Hawker Siddeley HS.801 Nimrod is not a Comet, it is a completely different aircraft from a different company, different factory decades later and has a different type certification.
The Nimrod has different wings, engines, fuselage and empennage, and different avionics and ancillary systems.
There are no significant parts or sub-assemblies shared in common.
*The Comet Disaster is the worst engineering failure in commercial jet aviation history.*
@sandervanderkammen9230
*UPDATE MORE BREAKING NEWS ETC*
De Havilland (Of England) Comets / Nimrods were not grounded after 1970 due to structural problems.
Of course it should indeed be noted that as far as flying stresses are concerned the Comet & Nimrod had particularly robust airframes.
*_It's interesting that some of the aircraft on the list should really have been noticeably safer than the Comet due to being a similar type but of much later design & manufacture but they definately were not safer._*
How things were back then -
*_Accident losses - % of aircraft built._*
DeHavilland Comet 4 UK 14%
DeHavilland Comet all mks 17%
Vickers VC10 UK 5%
*_The DH Comet had better safety than or similar safety to many other commercial passenger aircraft of a similar era_*
Douglas DC-1 99%
Douglas DC-2 47%
Douglas DC-3 30%
Douglas DC-4 26%
Boeing s300 72%
Boeing 307 70%
Boeing 247 48%
Boeing 707 20%
Lockheed L-049/149 Constellation 30%
Lockheed Electra Turboprop 29%
Fairchild FH-227 30%
McDonnell Douglas DC-8 14%
Sud Aviation Caravelle 15%
Canadair CL-44 Turboprop 46%
Convair CV-580 Turboprop 22%
A comparison of more recent aircraft.
Accident losses comparison examples.
1970s - 1980s
% of total Aircraft built
Similar aircraft type, date / decade, useage, size.
Biz Jets
BAe-125-800 1.7 %
Beechcraft Beechjet 400 2.2 %
Cessna 550 Citation II 7.1 %
Learjet 35 / 36 12 %
Beechcraft 1900 6%
Dassault Falcon 10 11.5%
Aérospatiale SN.601 22.5%
Medium size jets / Turboprops.
BAe-146 5.1%
Fokker 100 6%
McDonnell Douglas DC-9-30 9.5%
Fairchild FH-227 30%
McDonnell Douglas DC-8 14%
Canadair CL-44 Turboprop 46%
Convair CV-580 Turboprop 22%
Beechcraft, Fokker, McDonnell Douglass, Learjet, Fairchild, Aerospatiale, Canadair, Convair companies defunct.
All Comets, including some Comet 1s, had full civilian use certification at some point after 1954, civilian use certification only being withdrawn after commercial flying stopped. Examples were flying until 1997 - one example did a signals research global circumnavigation flight series in 1993 via Australia virtually without a rest travelling 28000 miles, only had an ice warning indicator issue during the flights.
*The DH Comet - World Firsts.*
1st gas turbine jet powered airliner. 1st high altitude 8psi pressurised full fuselage length passenger cabin airliner, not a trivial feature as structure strength required for pressurisation considerably exceeded strength required for normal flying stress. Nobody else had done anything similar before the Comet.
The b-47 used 2 relatively small, heavily built pressurised modules (the aircraft where 6 had their wings fold up in 2 months while flying & some had their wings fall off while parked).
The 1937 Boeing piston engined airliner pressurised passenger cabin was pressurised to 2 psi only - in fact that could easily be done as the normal unpressurized fuselage cabin structure strength for flying stresses only was all that was needed to be adequate so no significant weight increase issues needed addressing.
1st all hydraulically powered flying surface controls & actuators airliner with under carriage wheel disk brakes + ABS.
1st jet airliner to cross the Atlantic.
1st jet aircraft to do a world circumnavigation flights series.
*Of course De Havilland had prior experience building many all metal construction airframe aircraft including thousands of jet powered fighter aircraft that were primarily of metal construction with pressurised cockpits & jet engines built by De-Havilland & we know the world's first all metal construction airframe airliner was built in England in the 1920s by Handley Page.*
*_De Havilland did indeed always work to better than industry standards at the time, used up to date knowledge for the design & no evidence of negligence or criminal negligence was ever produced in relation to the DH Comet._*
The course of De Havilland & the general UK aerospace industry sector was not affected even slightly by the DH Comet.
*_Other interesting World firsts_*
_World's first turboprop aircraft._
*Vickers Viscount Turboprop Airliner 1947.*
*A 1945 Gloster Meteor Aircraft with Turboprop Gas Turbine Engine.*
People might like to have a go at these questions.
*Which airline has just ordered*
*60 RR England Trent XWB Engines*
*& What aircraft are the engines for?*
_Bonus question for 10 points._
Which country has the
*World's Highest Combined Per Capita*
*Nuclear + Defence + Aerospace Sector Activity?*
Cheers.
_Toodle_ -PIP- *Old* *_Chaps / Chapesses._*
..
@@petemaly8950 *Name a British jet aircraft still in production in the UK.???*
@@sandervanderkammen9230
_*Fryed Ryce Muncherz Krappenz DiktorBummer KARZEESTAN Jurkzxoffenzstadt & co - they should all note with much awestruckness and great wonderment.
*****
*How come they can't answer simple questions - why is that?*
*****
*_DID SOMEBODY ACTUALLY SAY SOMEWHERE THAT THERE'S AIRLINER ASSEMBLY LINES OR SIMILAR IN THE UK OR IRELAND OR THAT Airbus or BOW-WING is actually British? (B-47 wings on many occasions folded up in flight or dropped off while parked)._*
Of course Brazil makes very good airliners & Brazil is 100th down list along with Indonesia for wealth per capita.
*Norway Holland Denmark Ireland Belgium - Top 20 wealth per capita - Don't make airliners - its as simple as that.*
BAe Systems & RR combined now do more Airbus work than Germany on an absolute basis & significantly more work than that on a per capita basis.
Per capita for the home nation BAe Systems is the world's largest defence contractor.
_BAe systems announced the recent £4 Billion takeover of Colorado based US based Ball Aerospace._
*BAE systems now does a significantly higher value of work for Airbus than it did when it was a major Airbus shareholder before 2005.*
*_RR now owns US Engine maker Allison for example which does classified Aerospace work for the US Govt._*
The UK has more important stuff to do these days.
_Routine simple passenger aircraft airframe assembly is becoming more of a 3rd world / trailer park area thing._
EG -
*_The DH Comet - world's first high altitude capable pressurised passenger cabin jet airliner in regular service, world's first jet airliner aircraft to cross the Atlantic, worlds first jet airliner aircraft to complete a global circumnavigation flight series._*
*They might try to sensibly answer this question - why do they believe that BAE Systems & RR (aero engines etc) & other companies, for example should be doing anything other than what they currently do & where do they get the idea from that the DH Comet had any affect at all on the progression UK aerospace sector.*
*Anybody currently flying on a widebody airliner stands a good chance of being on an aircraft powered by RR gas turbine aero engines built in England.*
📯📯📯📯
*The New RR Trent Ultrafan*
*Built In England*
*_World's Largest (see T&Cs)_*
*_Gas Turbine Aero Engine_*
📯📯📯📯
👍Manufactured by the people on a small island with less than 1% of the world's population.👍
*_A typical but small glimpse of what goes on in the very internationally orientated British aerospace sector._* -
Boeing Apache Attack Helicopter.
AH-64: *75 UK suppliers,* 7% UK content, global fleet of 1280+ aircraft.
*F35B more than 130 UK Suppliers, more than 30% UK content.*
*_F35A & F35C more than 130 UK Suppliers, more than 15% UK content._*
They might like to answer these questions.
*Which airline has just ordered*
*60 RR England Trent XWB Engines*
*& What aircraft are the engines for?*
_Bonus question for 10 extra points._
Which country has the
*World's Highest Combined Per Capita*
*Nuclear / Defence / Aerospace Sector Activity?*
👍 & 🙂 & of course 😎 indeed.
*Cheers* &
_Toodle_ -PIP- *Old* *_Chap._*
. ... . . .. ...... . . .
.. . . ..... . .....
ccicci vvivvix
xixxiccicvcci
I flew in a Comet from Dublin to London and thought it was a beautiful aircraft.
You're very lucky to be alive... the Comet has the highest loss rate and fatalities statistics of any jet airliner in history
The problem was sorted at that stage for this pioneering aircraft regrettably the arrival of the B720/B707s on the scene nailed it sales prospects,@@sandervanderkammen9230
@hughdoyle7059 *The Comet 4 has the highest loss rate and fatalities statistics of any jet airliner in history except for the Comet 1.*
@hughdoyle7059 *Yes, the Boeing 707 certainly was a pioneering aircraft that completely revolutionized air travel and the aviation industry...its the first successful (airworthy) jet airliner in history.*
*Cheers mate.*
The commercial mistake (often repeated) was for the results of the British testing being shared with the US.
That's dark...😮
*That's a completely false narrative that completely crumbles upon the slightest scrutiny, the Boeing 707 series first flew on July 15th 1954, before anyone(including d-H) understood what caused the catastrophic in-flight structural failures.*
*The tragedy of the Comet Disaster was that it could have been easily prevented if de Havilland had simply followed well-known and understood industry standards pioneered by Boeing, Junkers, Douglas and Lockheed.*
@@sandervanderkammen9230
Kharzeestan Krappenz DiktorBummer Jurkzxoffenz etc and co - they should all note good with much awestruckness & extreme wonderment.
*UPDATE MORE BREAKING NEWS ETC*
The standard 707 doing airline duty only with no big military budget lasted about 22 years. Extensive modifications were made to the 707 design after the Comet incidents.
De Havilland (Of England) Comets were not grounded after 1970 due to structural problems.
*_It's interesting that some of the aircraft on the list should really have been noticeably safer than the Comet due to being a similar type but of much later design & manufacture but they definately were not safer._*
How things were back then -
*_Accident losses - % of aircraft built._*
DeHavilland Comet 4 UK 14%
DeHavilland Comet all mks 17%
Vickers VC10 UK 5%
*_The DH Comet had better safety than or similar safety to many other commercial passenger aircraft of a similar era_*
Douglas DC-1 99%
Douglas DC-2 47%
Douglas DC-3 30%
Douglas DC-4 26%
Boeing s300 72%
Boeing 307 70%
Boeing 247 48%
Boeing 707 20%
Lockheed L-049/149 Constellation 30%
Lockheed Electra Turboprop 29%
Fairchild FH-227 30%
McDonnell Douglas DC-8 14%
Sud Aviation Caravelle 15%
Canadair CL-44 Turboprop 46%
Convair CV-580 Turboprop 22%
A comparison of more recent aircraft.
Accident losses comparison examples.
1970s - 1980s
% of total Aircraft built
Similar aircraft type, date / decade, useage, size.
Biz Jets
BAe-125-800 1.7 %
Beechcraft Beechjet 400 2.2 %
Cessna 550 Citation II 7.1 %
Learjet 35 / 36 12 %
Beechcraft 1900 6%
Dassault Falcon 10 11.5%
Aérospatiale SN.601 22.5%
Medium size jets / Turboprops.
BAe-146 5.1%
Fokker 100 6%
McDonnell Douglas DC-9-30 9.5%
Fairchild FH-227 30%
McDonnell Douglas DC-8 14%
Canadair CL-44 Turboprop 46%
Convair CV-580 Turboprop 22%
Beechcraft, Fokker, McDonnell Douglass, Learjet, Fairchild, Aerospatiale, Canadair, Convair companies defunct.
All Comets, including some Comet 1s, had full civilian use certification at some point after 1954, civilian use certification only being withdrawn after commercial flying stopped. Examples were flying until 1997 - one example did a signals research global circumnavigation flight series in 1993 via Australia virtually without a rest travelling 28000 miles, only had an ice warning indicator issue during the flights.
*The DH Comet - World Firsts.*
1st gas turbine jet powered airliner. 1st high altitude 8psi pressurised full fuselage length passenger cabin airliner, not a trivial feature as structure strength required for pressurisation considerably exceeded strength required for normal flying stress. Nobody else had done anything similar before the Comet.
The b-47 used 2 relatively small, heavily built pressurised modules (the aircraft where 6 had their wings fold up in 2 months while flying & some had their wings fall off while parked).
The 1937 Boeing piston engined airliner pressurised passenger cabin was pressurised to 2 psi only - in fact that could easily be done as the normal unpressurized fuselage cabin structure strength for flying stresses only was all that was needed to be adequate so no significant weight increase issues needed addressing.
1st all hydraulically powered flying surface controls & actuators airliner with under carriage wheel disk brakes + ABS.
1st jet airliner to cross the Atlantic.
1st jet aircraft to do a world circumnavigation flights series.
*Of course De Havilland had prior experience building many all metal construction airframe aircraft including thousands of jet powered fighter aircraft that were primarily of metal construction with pressurised cockpits & jet engines built by De-Havilland & we know the world's first all metal construction airframe airliner was built in England in the 1920s by Handley Page.*
*_De Havilland did indeed always work to better than industry standards at the time, used up to date knowledge for the design & no evidence of negligence or criminal negligence was ever produced in relation to the DH Comet._*
The course of De Havilland & the general UK aerospace industry sector was not affected even slightly by the DH Comet.
*_Other interesting World firsts_*
_World's first turboprop aircraft._
*Vickers Viscount Turboprop Airliner 1947.*
*A 1945 Gloster Meteor Aircraft with Turboprop Gas Turbine Engine.*
They might like to answer these questions.
*Which airline has just ordered*
*60 RR England Trent XWB Engines*
*& What aircraft are the engines for?*
_Bonus question for 10 points._
Which country has the
*World's Highest Combined Per Capita*
*Nuclear + Defence + Aerospace Sector Activity?*
👍 & 🙂 & of course 😎 indeed.
*C H E E R S* & without doubt -
_Toodle_ -PIP- *Old* *_Chap._*
. .... . ... . ... ..
... .... ... ....
Ivcxivcxivcxcxii
vxvivcxiccxxcc
Where Ever etc
VERY interesting & informative!
Isn't it amazing how many different little details it takes to analyze a failure?
Now if only the airlines had kept the L-1011 in service, I'd bet that those bonded fuselages would still be running safe & sound... 80)
Chow Mein gobblers should be aware.
*_Accident losses - % of aircraft built._*
DeHavilland Comet 4 UK 14%
DeHavilland Comet all mks 17%
Vickers VC10 UK 5%
Boeing 707 USA *20%*
Lockheed Electra USA *29%*
Maybe they should have stopped flying out of rome
Well explained, sir.
Chow Mein gobblers should be aware.
*_Accident losses - % of aircraft built._*
DeHavilland Comet 4 UK 14%
DeHavilland Comet all mks 17%
Vickers VC10 UK 5%
Boeing 707 USA *20%*
Lockheed Electra USA *29%*
*The de Havilland Comet was the worst engineering failure in commercial jet aviation history.*
ha ha ... no that's your own 737
@Jack-bs6zb *Comet 1 had a 46% loss rate... that would be equal to over 6,000 Boeing 737 crashes...*
*Compared to the Comet, the 737 has an EXCELLENT statistical safety record.*
@@sandervanderkammen9230
Fryed Ryce Muncherz shud note -
*_How things were back then._*
*_Accident losses - % of aircraft built._*
DeHavilland Comet 4 UK 14%
DeHavilland Comet all mks 17%
Vickers VC10 UK 5%
Douglas DC-1 99%
Douglas DC-2 47%
Douglas DC-3 30%
Douglas DC-4 26%
Boeing s300 72%
Boeing 247 48%
Boeing 707 20%
Lockheed Electra 29%
@@Peppa_Wiggles23 *NAME A SINGLE BRITISH COMPANY THAT STILL MAKES BRITISH JET AIRCRAFT?*
Fryed Ryce Muncherz might like to recognise & must immediately & diligently memorize -??
*_DID SOMEBODY ACTUALLY SAY SOMEWHERE THAT THERE'S AIRLINER ASSEMBLY LINES OR SIMILAR IN THE UK OR IRELAND OR THAT Airbus is actually British?_*
*Of course Brazil make airliners - 100th down list along with Indonesia for wealth per capita.*
Norway Holland Denmark Ireland Belgium - Top 20 wealth per capita - Don't make airliners - totally as simple as that.
BAE systems announced recent £4 Billion takeover of Colorado based US based Ball Aerospace.
BAE systems now doesa significantly higher value of work for Airbus than it did when it was a major Airbus shareholder before 2005.
RR now owns US Engine maker Allison - does classified Aerospace work for the US Govt
The UK has more important stuff to do these days.
Routine Simple Passenger Aircraft Airframe assembly is becoming more of a 3rd world / trailer park area thing.
The comet gave way to the very successful bae Nimrod maritime aircraft
Search for - Report of The Court of Inquiry G-ALYP & G-ALYY. Then Paragraph 95 ... " The cause of the accident .... was the structural failure of the pressure cabin brought about by fatigue."
Excellent summary!
The engineering and manufacturing flaws of the Comet remind me of the same problems that plagued the Titanic…
Now, had the Comet not suffered these accidents and proven to be a good airplane, how would that have impacted DeHavilland and the British aerospace industry, as well as the US industry? I’d bet the same as today with a U.S. and European duopoly, but it probably would’ve happened sooner as opposed to the 80s.
The aircraft industry in the UK was already in deep trouble with the end of the war and to be honest de Havilland did not have a great reputation for safety before the Comet... in fact they were probably the least able to develop a large modern jet transport.
@@WilhelmKarsten
Wrong. You are presenting an entirely false picture.
The Comet simply attracted a lot of attention due to its highly advanced design & construction. DH was designing jet engine from first principles & building them.
DH used the most advanced design & construction techniques & processes anywhere in the world at the time.
The Comet was not built from plywood, chipboard & pva wood glue from the DIY store. In fact the highly advanced adhesives actually used are still currently manufactured & used in the aerospace industry.
Changes made to the aircraft were simply mostly to look like something was being done &:most changes were changes that would have been actioned regardless & many changes were carried out just in case. The original design & construction were good. There were problems but at the time that was expected.
The most significant changes were more powerful engines & pointing the engine exhausts away from the fuselage.
There was never a complete redesign.
@@Paul-mh9prThe facts are irrefutable, the Comet Disaster is the worst engineering failure in commercial aviation history.
The Comet has the highest loss rate and fatalities statistics of any jet airliner in history
@@Paul-mh9pr de Haviland was decades behind in aircraft technology and the real tragedy of the Comet Disaster was that it could have been easily prevented if de Haviland had simply followed well-known and understood industry standards for the design and construction of pressurized cabins made from riveted aluminum alloys.
The Comet Disaster is the result of gross engineering incompetence and criminal negligence.
A truly shameful and humiliating chapter in British aviation history
@@WilhelmKarsten
They might like to stop talking gibberish & provide sources for the various ridiculous claims they keep repeating parrot fashion might they not.
Anyway.
A Comparison - for an idea of how things were back then.
Lockheed Electra
US.
First flew 1957
First US turboprop airliner
4 engine turboprop.
Pressurised passenger cabin.
Three aircraft were lost in fatal accidents between February 1959 and March 1960. After the third crash, the FAA limited the Electra's speed until the cause could be determined.[7] After an extensive investigation, two of the crashes (in September 1959 and March 1960) were found to be caused by an engine-mount problem. The mounting of the gearbox cracked, and the reduced rigidity enabled a phenomenon called "whirl mode flutter"
Could cause wing destruction.
The three aircraft accidents did not result in the type being grounded.
Vickers Viscount.
UK.
First flew 1948, 10 years before the Electra.
4 engine turboprop.
RR Dart engines.
Pressurised passenger cabin.
As the Comet story shows: every reason has to have another reason to happen. The square windows were publicly blamed over decades. I even learned that from a technical publication in Germany in the late 60s - exposing how much engineers have learned from this "mishap" and used rounded windows solely. That however wasn't even half the truth as I learned much later. But - you know - you are always more clever in hindsight. How I see it ? The *engineers* at that time did what they supposedly could have done, approved and tested their theories intensely. Maybe in addition the pencil sharpeners might have torpedoed the work in a way due to complexity and therefore cost constrains using rivets instead of glue and smash in the rivets instead of drilling them for a faster production process. As usual. Thanks for showing !
The real tragedy of the Comet Disaster was that it could have been easily prevented if de Havilland had simply followed well-known and understood industry standards for design and construction of pressurized cabins made from riveted aluminum alloys.
The only lesson learned from the Comet Disaster was that aircraft manufacturers could no longer be trusted to conduct their own crash investigations (and de Havilland only had real experience in building aircraft made primarily from wood and fabric)
The shape of the passenger windows had absolutely nothing to do with the catastrophic in-flight structural failures... this red herring was debunked when wreckage was recovered from the sea.
Unfortunately, engineering incompetence and criminal negligence is responsible for the 492 innocent lives lost, a truly shameful and humiliating chapter in British history.
@@sandervanderkammen9230
@sandervanderkammen9230
Kharzeestan Krappenz DiktorBummer Jurkzxoffenz etc and co - they should all note good with much awestruckness & extreme wonderment.
*UPDATE MORE BREAKING NEWS ETC*
De Havilland (Of England) Comets were not grounded after 1970 due to structural problems.
*_It's interesting that some of the aircraft on the list should really have been noticeably safer than the Comet due to being a similar type but of much later design & manufacture but they definately were not safer._*
How things were back then -
*_Accident losses - % of aircraft built._*
DeHavilland Comet 4 UK 14%
DeHavilland Comet all mks 17%
Vickers VC10 UK 5%
*_The DH Comet had better safety than or similar safety to many other commercial passenger aircraft of a similar era_*
Douglas DC-1 99%
Douglas DC-2 47%
Douglas DC-3 30%
Douglas DC-4 26%
Boeing s300 72%
Boeing 307 70%
Boeing 247 48%
Boeing 707 20%
Lockheed L-049/149 Constellation 30%
Lockheed Electra Turboprop 29%
Fairchild FH-227 30%
McDonnell Douglas DC-8 14%
Sud Aviation Caravelle 15%
Canadair CL-44 Turboprop 46%
Convair CV-580 Turboprop 22%
A comparison of more recent aircraft.
Accident losses comparison examples.
1970s - 1980s
% of total Aircraft built
Similar aircraft type, date / decade, useage, size.
Biz Jets
BAe-125-800 1.7 %
Beechcraft Beechjet 400 2.2 %
Cessna 550 Citation II 7.1 %
Learjet 35 / 36 12 %
Beechcraft 1900 6%
Dassault Falcon 10 11.5%
Aérospatiale SN.601 22.5%
Medium size jets / Turboprops.
BAe-146 5.1%
Fokker 100 6%
McDonnell Douglas DC-9-30 9.5%
Fairchild FH-227 30%
McDonnell Douglas DC-8 14%
Canadair CL-44 Turboprop 46%
Convair CV-580 Turboprop 22%
Beechcraft, Fokker, McDonnell Douglass, Learjet, Fairchild, Aerospatiale, Canadair, Convair companies defunct.
All Comets, including some Comet 1s, had full civilian use certification at some point after 1954, civilian use certification only being withdrawn after commercial flying stopped. Examples were flying until 1997 - one example did a signals research global circumnavigation flight series in 1993 via Australia virtually without a rest travelling 28000 miles, only had an ice warning indicator issue during the flights.
*The DH Comet - World Firsts.*
1st gas turbine jet powered airliner. 1st high altitude 8psi pressurised full fuselage length passenger cabin airliner, not a trivial feature as structure strength required for pressurisation considerably exceeded strength required for normal flying stress. Nobody else had done anything similar before the Comet.
The b-47 used 2 relatively small, heavily built pressurised modules (the aircraft where 6 had their wings fold up in 2 months while flying & some had their wings fall off while parked).
The 1937 Boeing piston engined airliner pressurised passenger cabin was pressurised to 2 psi only - in fact that could easily be done as the normal unpressurized fuselage cabin structure strength for flying stresses only was all that was needed to be adequate so no significant weight increase issues needed addressing.
1st all hydraulically powered flying surface controls & actuators airliner with under carriage wheel disk brakes + ABS.
1st jet airliner to cross the Atlantic.
1st jet aircraft to do a world circumnavigation flights series.
*Of course De Havilland had prior experience building many all metal construction airframe aircraft including thousands of jet powered fighter aircraft that were primarily of metal construction with pressurised cockpits & jet engines built by De-Havilland & we know the world's first all metal construction airframe airliner was built in England in the 1920s by Handley Page.*
*_De Havilland did indeed always work to better than industry standards at the time, used up to date knowledge for the design & no evidence of negligence or criminal negligence was ever produced in relation to the DH Comet._*
The course of De Havilland & the general UK aerospace industry sector was not affected even slightly by the DH Comet.
*_Other interesting World firsts_*
_World's first turboprop aircraft._
*Vickers Viscount Turboprop Airliner 1947.*
*A 1945 Gloster Meteor Aircraft with Turboprop Gas Turbine Engine.*
They might like to answer these questions.
*Which airline has just ordered*
*60 RR England Trent XWB Engines*
*& What aircraft are the engines for?*
_Bonus question for 10 points._
Which country has the
*World's Highest Combined Per Capita*
*Nuclear + Defence + Aerospace Sector Activity?*
👍 & 🙂 & of course 😎 indeed.
*C H E E R S* & without doubt -
_Toodle_ -PIP- *Old* *_Chap._*
. .... . ... . ... .. ... ..
.. ... ....
Ivcxivcxivcxcx
iivxvivcxiccxxcc
Undoubtedly of course.
It was also that because de Haviland had to use a less powerful jet engine, the plane's metal skin was also thinner than originally envisaged. Had the Comet I went with a more powerful engine originally planned, the plane would have been built with a thicker skin, and it's likely the failures would not have happened until at least 2-3 years later in the life cycle of the plane.
The Comet 1 had many fatal flaws, being dangerously underpowered and made with unsuitable materials is just two of them.
The Comet 1 was found to have so many fatal flaws in its design that its airworthiness certification was permanently revoked.
de Havilland was forced to do a complete redesign of the entire aircraft to achieve certification.
@@sandervanderkammen9230@sandervanderkammen9230 😂Vickers Viscount 1st in the world Turboprop Pressurised Passenger Cabin Metal Construction Airliner flew 10 years before the Lockheed Electra Turboprop. The Viscount had a better safety record.
The Boeing 707 & Lockheed Electra had significantly worse safety numbers than the DH Comet.
No evidence of Dehavilland negligence or criminality or not working to better than industry standards at the time exists.
Karzeestan / vindurrkrapper
*Probably* exceedingly *_weird_* or what?
*AI Parrot Bot?*
Just the *FAX SONNY!*
*_ANSWER THE QUESTION LAD_*
*_Don't try intimating me boy._*
@@sandervanderkammen9230@sandervanderkammen9230 😂Vickers Viscount 1st in the world Turboprop Pressurised Passenger Cabin Metal Construction Airliner flew 10 years before the Lockheed Electra Turboprop. The Viscount had a better safety record.
The Boeing 707 & Lockheed Electra had significantly worse safety numbers than the DH Comet.
No evidence of Dehavilland negligence or criminality or not working to better than industry standards at the time exists.
Karzeestan / vindurrkrapper
*Probably* exceedingly *_weird_* or what?
*AI Parrot Bot?*
Just the *FAX SONNY!*
*_ANSWER THE QUESTION LAD_*
*_Don't try intimating me boy._*
@@Paul-mh9pr @petemaly8950 *HI Peppa Wiggles!*
*PLEASE NAME A SINGLE BRITISH COMPANY THAT STILL MAKES BRITISH JET AIRCRAFT IN THE UK?*
@@sandervanderkammen9230
*_WHAT_*
The fact that they punched the rivet holes is a massive 'red flag'. That operation induces cracks around the hole that need to be removed by drilling. You can NEVER get a clean separation of material when it is sheared. Ergo, ALL brackets require the edges to be polished after the guillotine process....especially in radius's
However, having said that it would have been far better to drill undersize & then 'Cold Worked' the holes to the required diameter. This method was used to increase the life of major structural components around the MLG support beam brackets on C130 aircraft.
Chow Mein gobblers should be aware.
*_Accident losses - % of aircraft built._*
DeHavilland Comet 4 UK 14%
DeHavilland Comet all mks 17%
Vickers VC10 UK 5%
Boeing 707 USA *20%*
Lockheed Electra USA *29%*
Yes it was
Many years ago I heard that the engineers had, in fact, intended to glue the window in, not rivet them. The sales team said that no buyer would buy the plane with glued windows, and insisted on rivets.
That's true, but the adhesive bonding was deleted to save money.
The important thing to remember is, as disturbing as this sounds the passenger windows had absolutely nothing to do with the catastrophic in-flight structural failures.
Wreckage recovered from the sea confirmed that the windows were not involved.
de Havilland used aluminum sheets that were far too thin on the top off the fuselage and chose the wrong alloy, AL2014B is too brittle.
The Comet also lacked proper overlapping Rip-stop doubler joints and the fuselage frame hoops were too narrow and spaced to far apart to prevent cracks from joining up with adjacent panels.
The square windows theory is nothing more than a red herring.
Chow Mein gobblers should be aware.
*_Accident losses - % of aircraft built._*
DeHavilland Comet 4 UK 14%
DeHavilland Comet all mks 17%
Vickers VC10 UK 5%
Boeing 707 USA *20%*
Lockheed Electra USA *29%*
. *Hey Pete, Paully Peppa!*
*NAME A BRITISH JET AIRCRAFT STILL IN PRODUCTION?*
@@sandervanderkammen9230
*WHAT*
* Neuronally challenged infantile Chow Mein Munchers should note*
*_DID SOMEBODY SAY THERE'S AIRLINER ASSEMBLY LINES OR SIMILAR IN THE UK OR IRELAND?_*
😅😅👍😅😅
@sandervanderkammen9230
*WHAT*
*Chow Mein Munchers should note*
*_DID SOMEBODY SAY THERE'S AIRLINER ASSEMBLY LINES OR SIMILAR IN THE UK OR IRELAND?_*
😅😅👍😅😅
During my time at A,V,Roe Woodford their Vulcan cabins were pressure tested for only 5psi and the hanger was cleared of none essentiol personel in spite of being much smaller than an airliner.
Chow Mein gobblers should be aware.
*_Accident losses - % of aircraft built._*
DeHavilland Comet 4 UK 14%
DeHavilland Comet all mks 17%
Vickers VC10 UK 5%
Boeing 707 USA *20%*
Lockheed Electra USA *29%*
The first airliner to fly would have been the canadian AVRO 102 called the AVRO JETLINER , but because avro's parent company was British they had the runway at Malton airport torn up for resurfacing when it was ready to fly ..making Canada loose at being first 😢😢
The first successful airworthy jet airliner is the Boeing Jet Stratoliner (707 family)
@@WilhelmKarsten
Wrong. You are presenting an entirely false picture.
The 707 was not a safe aircraft & was not the first jet airliner.
You are presenting an entirely false picture.
The Comet simply attracted a lot of attention due to its highly advanced design & construction. DH was designing jet engine from first principles & building them.
DH used the most advanced design & construction techniques & processes anywhere in the world at the time.
The Comet was not built from plywood, chipboard & pva wood glue from the DIY store. In fact the highly advanced adhesives actually used are still currently manufactured & used in the aerospace industry.
Changes made to the aircraft were simply mostly to look like something was being done &:most changes were changes that would have been actioned regardless & many changes were carried out just in case. The original design & construction were good. There were problems but at the time that was expected.
The most significant changes were more powerful engines & pointing the engine exhausts away from the fuselage.
There was never a complete redesign.
The Comet simply attracted a lot of attention due to its highly advanced design & construction. DH was designing jet engine from first principles & building them.
DH used the most advanced design & construction techniques & processes anywhere in the world at the time.
The Comet was not built from plywood, chipboard & pva wood glue from the DIY store. In fact the highly advanced adhesives actually used are still currently manufactured & used in the aerospace industry.
Changes made to the aircraft were simply mostly to look like something was being done &:most changes were changes that would have been actioned regardless & many changes were carried out just in case. The original design & construction were good. There were problems but at the time that was expected.
The most significant changes were more powerful engines & pointing the engine exhausts away from the fuselage.
There was never a complete redesign.
@@WilhelmKarsten
The Boeing 707 of course having a particularly bad safety record setting the record for the most people killed in one incident at the time.
As of January 2019, the Boeing 707 (865;aircraft built) has been in 261 incidents and 174 hull-loss accidents with a total of 3,039 fatalities. The deadliest incident involving the 707 was the Agadir air disaster which took place on August 3, 1975, with 188 fatalities.
On January 14, 2019, a Saha Airlines cargo flight crashed, killing 15 people and seriously injuring one more person. It was the last civil 707 in operation.
@@Paul-mh9pr There is absolutely no evidence to support your twisted, false revisionist narrative.
de Havilland was still building wood and fabric covered biplanes when Junkers invented the first all-metal, fully pressurized aircraft in 1931.
The Junkers Ju-86 was flying pressurized to over 52,000 feet during WW2.
Boeing built the first pressurized airliner in 1938, followed by Lockheed, Douglas and Junkers.
These were all-metal aircraft.
De Havilland was still building aircraft primarily from wood and fabric well into the Jet Age.
@@Paul-mh9pr There were almost 2,000 aircraft in the Boeing Jet Stratoliner series including all the variants.
Only 114 Comets were ever built.
The Comet has the worst safety record of ANY jet transport aircraft with the highest loss rate and fatalities statistics.
The Boeing 707 family is still in service and is expected to remain flying until at least 2050.
Comet 4 was grounded in 1980 due to metal fatigue damage.
The conclusion of the fastening method being the origin of the fatal cracks is fascinating. Proof that science is seldom "Settled" and we need to keep an open and inquiring mind.
People seem to be more focused on the origin of the crack, this is not what caused the catastrophic in-flight structural failures.
We find small cracks on planes all the time, the issue with Comet, it's fatal flaw was what allowed these cracks to spread and join up so rapidly that it ripped the plane apart.
de Havilland cut corners, allowed narrow safety margins, made bad calculations and produced faulty test data.
This was a direct result of attempting to save weight at the expense of safety and durability.
What killed 426 people was just bad design and construction methods
@@WilhelmKarsten
Wrong. You are presenting an entirely false picture.
The Comet simply attracted a lot of attention due to its highly advanced design & construction. DH was designing jet engine from first principles & building them.
DH used the most advanced design & construction techniques & processes anywhere in the world at the time.
The Comet was not built from plywood, chipboard & pva wood glue from the DIY store. In fact the highly advanced adhesives actually used are still currently manufactured & used in the aerospace industry.
Changes made to the aircraft were simply mostly to look like something was being done &:most changes were changes that would have been actioned regardless & many changes were carried out just in case. The original design & construction were good. There were problems but at the time that was expected.
The most significant changes were more powerful engines & pointing the engine exhausts away from the fuselage.
There was never a complete redesign.
@@Paul-mh9prThe facts are irrefutable, the Comet Disaster is the worst engineering failure in commercial aviation history.
The Comet has the highest loss rate and fatalities statistics of any jet airliner in history
@@Paul-mh9prde Haviland was decades behind in aircraft technology and the real tragedy of the Comet Disaster was that it could have been easily prevented if de Haviland had simply followed well-known and understood industry standards for the design and construction of pressurized cabins made from riveted aluminum alloys.
The Comet Disaster is the result of gross engineering incompetence and criminal negligence.
A truly shameful and humiliating chapter in British aviation history
@@WilhelmKarsten
They might like to stop talking gibberish & provide sources for the various ridiculous claims they keep repeating parrot fashion might they not.
Anyway.
A Comparison - for an idea of how things were back then for anyone interested in facts
Lockheed Electra
US.
First flew 1957
First US turboprop airliner
4 engine turboprop.
Pressurised passenger cabin.
Three aircraft were lost in fatal accidents between February 1959 and March 1960. After the third crash, the FAA limited the Electra's speed until the cause could be determined.[7] After an extensive investigation, two of the crashes (in September 1959 and March 1960) were found to be caused by an engine-mount problem. The mounting of the gearbox cracked, and the reduced rigidity enabled a phenomenon called "whirl mode flutter"
Could cause wing destruction.
The three aircraft accidents did not result in the type being grounded for some reason that nobody can put their finger on or get to the bottom of.
Vickers Viscount.
UK.
First flew 1948, 10 years before the Electra.
4 engine turboprop.
RR Dart engines.
Pressurised passenger cabin.
At the time of the DH Comet DH of course were designing jet engines from first principles & manufacturing the jet engines.
About 25 years ago there was a TV programme in England about the comet and amongst other things it was made clear that the engineers knew at the time that the skin was too thin but they were overruled when they made objections because it was necessary to use the thin skin to save on weight.
It was a great plane but also a disaster and it paid the price for being a pioneer
de Havilland was no pioneer in pressurized aircraft, they lagged decades behind in modern aircraft technology.
Comet 1 had numerous fatal design flaws including aluminum skins that were too thin but also inferior materials that were too brittle and lacked critical overlapping rip-stop doubler joints.
Inadequate riveted fastners and poor quality control.
The fuselage reinforcement hoops were too weak and spaced too far apart to prevent cracks from joining up with adjacent panels.
2 crashed as a direct result of the fatally flawed placement of the engine inlets in the wings leading edge along with flaps that were ineffective and a flawed hydraulic flight control system.
de Havilland installed thicker skins and smaller windows but the Comet 1 was deemed too unsafe and it's airworthiness certification was permanently revoked.
The Comet 4 is a completely redesigned aircraft that share a little in common with the deadly Comet 1.
This would have made Boeing jealous.
@@Torontotootwo Why would Boeing be jealous? Their aircraft were a decade ahead of anything that de Havilland had.
@@TorontotootwoBoeing built the first successful airworthy jet airliner
@@WilhelmKarsten
*_Accident losses - % of aircraft built._*
DeHavilland Comet 4 UK 14%
DeHavilland Comet all mks 17%
Vickers VC10 UK 5%
Boeing 707 USA *20%*
Lockheed Electra USA *29%*
Extremely interesting. If they had only had that foresight back in those pioneering days of jet passenger aircraft.
Boeing, Douglas, Junkers and Lockheed did... it was de Havillands that lagged more than a decade behind in aircraft technology.
Karzeestan / vindurrkrapper
*Probably* exceedingly *_weird_* or what?
*AI Parrot Bot?*
Just the *FAX SONNY!*
*_ANSWER THE QUESTION SONNY_*
Vickers Viscount 1st in the world Turboprop Pressurised Passenger Cabin Metal Construction Airliner flew 10 years before the Lockheed Electra Turboprop. The Viscount had a better safety record.
The Boeing 707 & Lockheed Electra had significantly worse safety numbers than the DH Comet.
Karzeestan / vindurrkrapper
*Probably* exceedingly *_weird_* or what?
*AI Parrot Bot?*
Just the *FAX SONNY!*
*_ANSWER THE QUESTION LAD_*
@@Paul-mh9pr @petemaly8950 *HI Peppa Wiggles!*
*PLEASE NAME A SINGLE BRITISH COMPANY THAT STILL MAKES BRITISH JET AIRCRAFT IN THE UK?*
@@sandervanderkammen9230
Vickers Viscount 1st in the world Turboprop Pressurised Passenger Cabin Metal Construction Airliner flew 10 years before the Lockheed Electra Turboprop. The Viscount had a better safety record.
The Boeing 707 & Lockheed Electra had significantly worse safety numbers than the DH Comet.
Boeing 707 29% Accident Airframe losses.
Lockheed Electra 29% Accident Airframe losses.
DH Comet 17% Accident Airframe losses.
No evidence of Dehavilland negligence or criminality or not working to better than industry standards at the time exists.
Karzeestan / vindurrkrapper
*Probably* exceedingly *_weird_* or what?
*AI Parrot Bot?*
Just the *FAX SONNY!*
*_ANSWER THE QUESTION LAD_*
*_Don't try intimating me boy._*
Thanks for sharing. 😉👌🏻
Chow Mein gobblers should be aware.
*_Accident losses - % of aircraft built._*
DeHavilland Comet 4 UK 14%
DeHavilland Comet all mks 17%
Vickers VC10 UK 5%
Boeing 707 USA *20%*
Lockheed Electra USA *29%*
Chow Mein gobblers should be aware.
*_Accident losses - % of aircraft built._*
DeHavilland Comet 4 UK 14%
DeHavilland Comet all mks 17%
Vickers VC10 UK 5%
Boeing 707 USA *20%*
Lockheed Electra USA *29%*
I believe that the windows and reinforcement was designed to be glued in but this was changed by production for same unknown reasons.
The Comet had aluminum skins that were too thin and made from an alloy that was too brittle.
The Comet also lacked Rip-stop doubler joints and the wrong methods were used to install the rivets
@@WilhelmKarsten
Problems involved included for example the antenna hatch having been reworked badly due to manufacturing errors when it should have been scrapped.
The basic design was good & there is no evidence that there was anything wrong with the early DH Comets.
@@Paul-mh9pr Comet 1 was riddled with fatal design flaws, serious engineering incompetence and criminal negligence
@@WilhelmKarsten
@WilhelmKarsten
Provide evidence with links to sources that the DH Comet was not the most advanced high altitude pressurised passenger cabin jet airliner in the world at the time using design methods & construction methods & materials that were always better than industry standard. Including the design & materials selection for upholstery, toilet roll holders, light switches, curtains, partitions, bulkheads, pressure bulkheads, door handles, plumbing pipes & magazine holders.
Also provide evidence with links to sources that DH were guilty of criminal negligence.
Of course Most changes made were simply to look like changes had been made.
Comparison - for an idea of how things were back then generally -
Lockheed Electra
US.
First flew 1957 10 years after the Viscount.
First US turboprop airliner
4 engine turboprop.
Pressurised passenger cabin.
Of the total of 170 Electras built, as of June 2011, 58 have been written off because of crashes and other accidents.
29% of aircraft in hull loss accidents.
6 fatalities per aircraft.
Hull-losses: 59
Hull-loss accidents: 49
with a total of 1037 fatalities
Criminal occurences (hull-losses ): 1
with a total of 0 fatalities
Hijackings: 6
with a total of 1 fatalities
Survival rate:
12.0% of all occupants survived fatal accidents.
Three aircraft were lost in fatal accidents between February 1959 and March 1960. After the third crash, the FAA limited the Electra's speed until the cause could be determined.[7] After an extensive investigation, two of the crashes (in September 1959 and March 1960) were found to be caused by an engine-mount problem. The mounting of the gearbox cracked, and the reduced rigidity enabled a phenomenon called "whirl mode flutter"
Could cause wing destruction.
The three aircraft accidents did not result in the type being grounded for some unfathomable reason, odd isn't it?
Vickers Viscount.
UK.
First flew 1948 10 years before the Electra.
4 engine turboprop.
RR Dart engines.
Pressurised passenger cabin.
All 707s that were doing full time airline service are now scrapped or in museums. The only aircraft still flight worthy are those that were military or became military before the end of their design life or are in long term storage, or are engaged in low hours situations & so all have generally very low flying hours.
@@petemaly8950 *JUST NAME A SINGLE BRITISH COMPANY THAT STILL MAKES BRITISH JET AIRCRAFT IN THE UK?*
I remember these trajedies as I remember Concorde's. A terrible shame in each case. I don't know which was worse.
Certainly the two biggest financial failures in history..
Both were disasters for the UK aircraft industry which was already in a tailspin and headed for total collapse.
Okay! So it wasn't the square windows, but it was the square windows? "Failure of the skin in fatigue at the corner of a window, originating at a small defect in the skin. "
It wasn't the windows, the wreckage recovered later confirmed that they were not involved in the catastrophic in-flight structural failures.
Further investigation shows that any cracks at that frame station would have resulted in a catastrophic crack propagating along the carbin towards the tail ripping the aircraft apart.
The airframe was simply too weak.
The aluminum skins were too thin and too brittle, the lack of proper Rip-stop doubler joints and the fuselage frame hoops were too thin and spaced too far apart to prevent cracks from joining up with adjacent panels.
@@WilhelmKarsten
Supply sources for the claims.
DH was designing from first principles & building jet engines at the time.
The Comet was one of the most advanced passenger aircraft to be built at the time.
The design was essentially ok & one of the aircraft that crashed showed evidence of having a number of manufacturing faults involving the antenna hatch assembly which somehow ended up being used when it should have been scrapped.
Construction & riveting were to normal industry standards at the time.
@@Paul-mh9pr The Comet had aluminum skins that were too thin, just 1mm thick and made from an alloy that was too brittle and completely unsuitable.
de Havilland used AL2014B a material that was way below Industry standards at the time.
The Comet lacked proper Rip-stop doubler joints, another well-known Industry standard.
de Havilland used punch cut rivet holes and formed the rivet head with a hydraulic press tool... an extremely crude, primitive technique that was well below industry standards
The fuselage frame hoops were too narrow and weak, they were spaced too far apart to prevent cracks from joining up with adjacent panels, this and the other design defects combined to allow tiny cracks to join up and propagating instanously to cause the catastrophic in-flight structural failures
@@WilhelmKarsten
Provide evidence with links to sources that the DH Comet was not the most advanced high altitude pressurised passenger cabin jet airliner in the world at the time using design methods & construction methods & materials that were always better than industry standard. Including the design & materials selection for upholstery, toilet roll holders, light switches, curtains, partitions, bulkheads, pressure bulkheads, door handles, plumbing pipes & magazine holders.
Also provide evidence with links to sources that DH were guilty of criminal negligence.
Comparison - for an idea of how things were back then -
Lockheed Electra
US.
First flew 1957 10 years after the Viscount.
First US turboprop airliner
4 engine turboprop.
Pressurised passenger cabin.
Of the total of 170 Electras built, as of June 2011, 58 have been written off because of crashes and other accidents.
29% of aircraft in hull loss accidents.
6 fatalities per aircraft.
Hull-losses: 59
Hull-loss accidents: 49
with a total of 1037 fatalities
Criminal occurences (hull-losses ): 1
with a total of 0 fatalities
Hijackings: 6
with a total of 1 fatalities
Survival rate:
12.0% of all occupants survived fatal accidents.
Three aircraft were lost in fatal accidents between February 1959 and March 1960. After the third crash, the FAA limited the Electra's speed until the cause could be determined.[7] After an extensive investigation, two of the crashes (in September 1959 and March 1960) were found to be caused by an engine-mount problem. The mounting of the gearbox cracked, and the reduced rigidity enabled a phenomenon called "whirl mode flutter"
Could cause wing destruction.
The three aircraft accidents did not result in the type being grounded for some unfathomable reason, odd isn't it?
Vickers Viscount.
UK.
First flew 1948 10 years before the Electra.
4 engine turboprop.
RR Dart engines.
Pressurised passenger cabin.
All 707s that were doing full time airline service are now scrapped or in museums. The only aircraft still flight worthy are those that were military or became military before the end of their design life or are in long term storage, or are engaged in low hours situations & so all have generally very low flying hours.
@@petemaly8950 *JUST NAME A SINGLE BRITISH COMPANY THAT STILL MAKES BRITISH JET AIRCRAFT IN THE UK?*
The 1951 movie No Highway in the Sky (Jimmy Stewart, Marlene Dietrich) has a plot eerily built around a new model of airliner suffering metal fatigue - 5 years before the Comet crashed & before the Comet entered service.
Amazing…I had seen the movie and always assumed it was based on the Comet crashes. Nope-1951, based on a novel from 1948. Even novelists knew about metal fatigue
One thing I’ve always wondered about: why did they do the ultimate load (not sure if that’s the right term) test before the fatigue testing? First, wouldn’t certification require that fuselage meet the (seemingly modest) ultimate load requirements at the end of its life? Second, if you’re going to use the same fuselage AND plan on testing to well past the certification standards, it would make sense to have all the testing complete in case it failed at, say, 1.9 times the design load.
Great video. I’m pretty familiar with the content, but stayed interested throughout. Looking forward to more of your work
No Highway is a 1948 novel by Nevil Shute
Chow Mein gobblers should be aware.
*_Accident losses - % of aircraft built._*
DeHavilland Comet 4 UK 14%
DeHavilland Comet all mks 17%
Vickers VC10 UK 5%
Boeing 707 USA *20%*
Lockheed Electra USA *29%*
Chow Mein gobblers should be aware.
*_Accident losses - % of aircraft built._*
DeHavilland Comet 4 UK 14%
DeHavilland Comet all mks 17%
Vickers VC10 UK 5%
Boeing 707 USA *20%*
Lockheed Electra USA *29%*
An interesting post, for sure! Gluing alone has good resistance to tension but poor peel strength. Bonded and riveted laminated structures have both resistance to tension and good peel resistance. Forming the rivet holes at the time was likely fraught with danger. Punched holes are perfectly round as opposed to drilled holes. I've yet to see a demonstrably perfect round hole in an aluminium skin. Media or laser cutting was not a technology used at the time. It was probably perceived as a way to create a "Better" hole formed by punching. I'd hazard a guess that punched holes create a bit of localised work hardening of the immediate area. THE problem for the early jet airliner builders was a lack of proper information as the technology at the time was still new. Heat treating the finished skins after the holes were punched was likely no to have been thought of at the time. We need to remember it was only 50 years before these aircraft that powered flight used bicycle parts and wood frames covered with cloth!
AL2014B is not a suitable alloy for pressurized cabins and the skins on the crown of the cabin were only half the thickness of the sides (just 1mm) far too thin.
The Comet lacked proper overlapping Rip-stop doubler joints and the fuselage frame hoops were too narrow and spaced to far apart to prevent cracks from joining up with adjacent panels.
Drilling and reaming rivet holes was the industry standard as was pre-dimpling before rivet setting and head forming.
Die cutting and press forming was not suitable for riveting pressure skins, quality control standards at de Havilland was poor. Significant cracks were found that created during assembly and escaped inspection.
😂Vickers Viscount 1st in the world Turboprop Pressurised Passenger Cabin Metal Construction Airliner flew 10 years before the Lockheed Electra Turboprop. The Viscount had a better safety record.
The Boeing 707 & Lockheed Electra had significantly worse safety numbers than the DH Comet.
No evidence of Dehavilland negligence or criminality or not working to better than industry standards at the time exists.
Karzeestan / vindurrkrapper
*Probably* exceedingly *_weird_* or what?
*AI Parrot Bot?*
Just the *FAX SONNY!*
*_ANSWER THE QUESTION LAD_*
*_Don't try intimating me boy._*
@@WilhelmKarsten
@sandervanderkammen9230
They might like to consider -
Comet Accident Losses Brief Comparison.
A brief comparison & view of how thing were then.
Accident Losses, % of total Aircraft built.
Lockheed Electra. USA. Turboprop.
29% Accident Losses
Vickers Viscount UK
29% Accident Losses
1st turboprop pressurised cabin metal airframe construction aircraft in the world. 10 years ahead of the Lockheed Electra.
Boeing 707 USA
20% Accident Losses
DeHavilland Comet all mks UK
17% Accident Losses
DeHavilland Comet 4 UK
14% Accident Losses
Vickers VC10 UK
A very popular aircraft with passengers,
BOAC continually lied about it being loss making in order to obtain govt subsidies.
5% Accident Losses & had a very good passenger crash survival rate for the period.
@@Paul-Nicer58 *Please name a single British company that still makes British jet aircraft in the UK???*
@@sandervanderkammen9230
Chiney leydies should be vlly aware -
De Havilland were making many all metal construction airframe aircraft before the Comet.
The world's first all metal construction airframe airliner was produced by Handley Page in the 1920s.
Accident loss rates - % of total built -
Comet all mks 17%
Comet 4 14%
Vickers VC10 5%
Douglas DC-1 99%
Douglas DC-2 47%
Douglas DC-3 30%
Douglas DC-4 26%
Boeing s300 Stratoliner 72%
Boeing 247 48%
Boeing 707 USA . *20%*
Lockheed Electra USA. *29%*
OK so they should have over pressurised the fuselage before putting it into service.
They should have learned to build planes out of metal... de Havilland only knew how to build planes made of wood and fabric
@@sandervanderkammen9230
Kharzeestan Krappenz DiktorBummer Jurkzxoffenz etc and co - they should all note good with much awestruckness & extreme wonderment.
*UPDATE MORE BREAKING NEWS ETC*
De Havilland (Of England) Comets were not grounded after 1970 due to structural problems.
*_It's interesting that some of the aircraft on the list should really have been noticeably safer than the Comet due to being a similar type but of much later design & manufacture but they definately were not safer._*
How things were back then -
*_Accident losses - % of aircraft built._*
DeHavilland Comet 4 UK 14%
DeHavilland Comet all mks 17%
Vickers VC10 UK 5%
*_The DH Comet had better safety than or similar safety to many other commercial passenger aircraft of a similar era_*
Douglas DC-1 99%
Douglas DC-2 47%
Douglas DC-3 30%
Douglas DC-4 26%
Boeing s300 72%
Boeing 307 70%
Boeing 247 48%
Boeing 707 20%
Lockheed L-049/149 Constellation 30%
Lockheed Electra Turboprop 29%
Fairchild FH-227 30%
McDonnell Douglas DC-8 14%
Sud Aviation Caravelle 15%
Canadair CL-44 Turboprop 46%
Convair CV-580 Turboprop 22%
A comparison of more recent aircraft.
Accident losses comparison examples.
1970s - 1980s
% of total Aircraft built
Similar aircraft type, date / decade, useage, size.
Biz Jets
BAe-125-800 1.7 %
Beechcraft Beechjet 400 2.2 %
Cessna 550 Citation II 7.1 %
Learjet 35 / 36 12 %
Beechcraft 1900 6%
Dassault Falcon 10 11.5%
Aérospatiale SN.601 22.5%
Medium size jets / Turboprops.
BAe-146 5.1%
Fokker 100 6%
McDonnell Douglas DC-9-30 9.5%
Fairchild FH-227 30%
McDonnell Douglas DC-8 14%
Canadair CL-44 Turboprop 46%
Convair CV-580 Turboprop 22%
Beechcraft, Fokker, McDonnell Douglass, Learjet, Fairchild, Aerospatiale, Canadair, Convair companies defunct.
All Comets, including some Comet 1s, had full civilian use certification at some point after 1954, civilian use certification only being withdrawn after commercial flying stopped. Examples were flying until 1997 - one example did a signals research global circumnavigation flight series in 1993 via Australia virtually without a rest travelling 28000 miles, only had an ice warning indicator issue during the flights.
*The DH Comet - World Firsts.*
1st gas turbine jet powered airliner. 1st high altitude 8psi pressurised full fuselage length passenger cabin airliner, not a trivial feature as structure strength required for pressurisation considerably exceeded strength required for normal flying stress. Nobody else had done anything similar before the Comet.
The b-47 used 2 relatively small, heavily built pressurised modules (the aircraft where 6 had their wings fold up in 2 months while flying & some had their wings fall off while parked).
The 1937 Boeing piston engined airliner pressurised passenger cabin was pressurised to 2 psi only - in fact that could easily be done as the normal unpressurized fuselage cabin structure strength for flying stresses only was all that was needed to be adequate so no significant weight increase issues needed addressing.
1st all hydraulically powered flying surface controls & actuators airliner with under carriage wheel disk brakes + ABS.
1st jet airliner to cross the Atlantic.
1st jet aircraft to do a world circumnavigation flights series.
*Of course De Havilland had prior experience building many all metal construction airframe aircraft including thousands of jet powered fighter aircraft that were primarily of metal construction with pressurised cockpits & jet engines built by De-Havilland & we know the world's first all metal construction airframe airliner was built in England in the 1920s by Handley Page.*
*_De Havilland did indeed always work to better than industry standards at the time, used up to date knowledge for the design & no evidence of negligence or criminal negligence was ever produced in relation to the DH Comet._*
The course of De Havilland & the general UK aerospace industry sector was not affected even slightly by the DH Comet.
*_Other interesting World firsts_*
_World's first turboprop aircraft._
*Vickers Viscount Turboprop Airliner 1947.*
*A 1945 Gloster Meteor Aircraft with Turboprop Gas Turbine Engine.*
They might like to answer these questions.
*Which airline has just ordered*
*60 RR England Trent XWB Engines*
*& What aircraft are the engines for?*
_Bonus question for 10 points._
Which country has the
*World's Highest Combined Per Capita*
*Nuclear + Defence + Aerospace Sector Activity?*
👍 & 🙂 & of course 😎 indeed.
*C H E E R S* & without doubt -
_Toodle_ -PIP- *Old* *_Chap._*
. .... . ... . .. ...... ..
... .... ... ....
Ivcxivcxivcvcxcx
iivxvivcxcciccxxcc
Where
No but the stress concentrations caused by the sharp corners of the windows contributed to the mid air explosive decompresion. The faiture was initiated from a rivet hole defect at a cut out for the ADF on top of the fuselage at the front. A fatigue crack propagated from that defect eventually becoming critical and the rest is history.
The evidence has completely debunked the square windows theory... it had absolutely nothing to do with the shape of the windows.
@@WilhelmKarsten
Kharzeestan Krappenz DiktorBummer Jurkzxoffenz etc and co - they should all note good with much awestruckness & extreme wonderment.
*UPDATE MORE BREAKING NEWS ETC*
De Havilland (Of England) Comets were not grounded after 1970 due to structural problems.
*_It's interesting that some of the aircraft on the list should really have been noticeably safer than the Comet due to being a similar type but of much later design & manufacture but they definately were not safer._*
How things were back then -
*_Accident losses - % of aircraft built._*
DeHavilland Comet 4 UK 14%
DeHavilland Comet all mks 17%
Vickers VC10 UK 5%
*_The DH Comet had better safety than or similar safety to many other commercial passenger aircraft of a similar era_*
Douglas DC-1 99%
Douglas DC-2 47%
Douglas DC-3 30%
Douglas DC-4 26%
Boeing s300 72%
Boeing 307 70%
Boeing 247 48%
Boeing 707 20%
Lockheed L-049/149 Constellation 30%
Lockheed Electra Turboprop 29%
Fairchild FH-227 30%
McDonnell Douglas DC-8 14%
Sud Aviation Caravelle 15%
Canadair CL-44 Turboprop 46%
Convair CV-580 Turboprop 22%
A comparison of more recent aircraft.
Accident losses comparison examples.
1970s - 1980s
% of total Aircraft built
Similar aircraft type, date / decade, useage, size.
Biz Jets
BAe-125-800 1.7 %
Beechcraft Beechjet 400 2.2 %
Cessna 550 Citation II 7.1 %
Learjet 35 / 36 12 %
Beechcraft 1900 6%
Dassault Falcon 10 11.5%
Aérospatiale SN.601 22.5%
Medium size jets / Turboprops.
BAe-146 5.1%
Fokker 100 6%
McDonnell Douglas DC-9-30 9.5%
Fairchild FH-227 30%
McDonnell Douglas DC-8 14%
Canadair CL-44 Turboprop 46%
Convair CV-580 Turboprop 22%
Beechcraft, Fokker, McDonnell Douglass, Learjet, Fairchild, Aerospatiale, Canadair, Convair companies defunct.
All Comets, including some Comet 1s, had full civilian use certification at some point after 1954, civilian use certification only being withdrawn after commercial flying stopped. Examples were flying until 1997 - one example did a signals research global circumnavigation flight series in 1993 via Australia virtually without a rest travelling 28000 miles, only had an ice warning indicator issue during the flights.
*The DH Comet - World Firsts.*
1st gas turbine jet powered airliner. 1st high altitude 8psi pressurised full fuselage length passenger cabin airliner, not a trivial feature as structure strength required for pressurisation considerably exceeded strength required for normal flying stress. Nobody else had done anything similar before the Comet.
The b-47 used 2 relatively small, heavily built pressurised modules (the aircraft where 6 had their wings fold up in 2 months while flying & some had their wings fall off while parked).
The 1937 Boeing piston engined airliner pressurised passenger cabin was pressurised to 2 psi only - in fact that could easily be done as the normal unpressurized fuselage cabin structure strength for flying stresses only was all that was needed to be adequate so no significant weight increase issues needed addressing.
1st all hydraulically powered flying surface controls & actuators airliner with under carriage wheel disk brakes + ABS.
1st jet airliner to cross the Atlantic.
1st jet aircraft to do a world circumnavigation flights series.
*Of course De Havilland had prior experience building many all metal construction airframe aircraft including thousands of jet powered fighter aircraft that were primarily of metal construction with pressurised cockpits & jet engines built by De-Havilland & we know the world's first all metal construction airframe airliner was built in England in the 1920s by Handley Page.*
*_De Havilland did indeed always work to better than industry standards at the time, used up to date knowledge for the design & no evidence of negligence or criminal negligence was ever produced in relation to the DH Comet._*
The course of De Havilland & the general UK aerospace industry sector was not affected even slightly by the DH Comet.
*_Other interesting World firsts_*
_World's first turboprop aircraft._
*Vickers Viscount Turboprop Airliner 1947.*
*A 1945 Gloster Meteor Aircraft with Turboprop Gas Turbine Engine.*
They might like to answer these questions.
*Which airline has just ordered*
*60 RR England Trent XWB Engines*
*& What aircraft are the engines for?*
_Bonus question for 10 points._
Which country has the
*World's Highest Combined Per Capita*
*Nuclear + Defence + Aerospace Sector Activity?*
👍 & 🙂 & of course 😎 indeed.
Cheers.
_Toodle_ -PIP- *Old* *_Chap._*
. .... . ... .
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xvivcxiccxxcc
The 'square windows' myth (they had rounded corners) has been comprehensively debunked numerous times over the years.
I recommend that you look for the following on CZcams:
The deHavilland Comet Disaster - a Story of Fatigue, a lecture given by Prof Paul Withey.
It's the video of a lecture I attended on 28 April 2019.
He absolutely debunks the myth.
Excellent comment, Yes, it's a very good lecture.
@WilhelmKarsten The Comet 1's windows were actually rectangular with rounded corners. If you take a look at a B.737 and imagine its windows rotated through 90 degrees, they would be almost identical to the Comet's windows, with only a small increase in the corner radii.
Does anyone on here know why the Comet, so far as I know, was the only airliner to have the engines integrated with the wings? This seems to be more elegant and, to someone like me who knows nothing about these matters, less stressful on the structure than having them hanging on brackets from the wings?
The Comet's engine configuration makes for a clean pleasing look. However, there are some drawbacks to the design. Turbojet engines like a clean smooth airflow to operate well. In a tight turn airflow to wing root mounted engines is somewhat negatively impacted by turbulence caused by the fuselage. The main wing spar (the part that gives wings their strength) has to pass by the engines close to the point of maximum stress, ie. close to the fuselage, this adds complexity and weight to the design. Another issue, especially with early turbojets, was engine maintenance, access is much easier with wing mounted pod engines. Lastly, wing mounted engines load the wing more evenly than root mounted engines, meaning the main spar is loaded less at the wing root and can be lighter. Having said all of that, it’s still my view that the Comet was a most beautiful, if sadly flawed, aircraft.
@petcatznz thanks for your detailed and informative reply. Aspects of design at which I would never have guessed. And yes you are right, the Comet did look good, even futuristic, but sadly not so practical.
*De Havilland designed the Comet based on a popular aerodynamic theory at the time that proved to be later found in testing to be completely wrong.*
*The placement of the engine inlets in the wings leading edge proved to be a fatal flaw that is responsible for several hull loss accidents.*
*No other aircraft manufacturers have ever copied this design flaw, it is widely known as an example of bad aerodynamic theory and practice.*
@@sandervanderkammen9230 thanks 🙂
The Canadian built Avro Jetliner, which first flew days after the Comet’s first flight, also had engines enclosed within the wings….. but not quite as fully enclosed as the Comet.
Saving pennies costs lives as simple as that
British planes are not very safe... even British operators refused to buy them
@@WilhelmKarsten
😂
Vickers Viscount 1st in the world Turboprop Pressurised Passenger Cabin Metal Construction Airliner flew 10 years before the Lockheed Electra Turboprop. The Viscount had a better safety record.
The Boeing 707 & Lockheed Electra had significantly worse safety numbers than the DH Comet.
No evidence of Dehavilland negligence or criminality or not working to better than industry standards at the time exists.
Karzeestan / vindurrkrapper
*Probably* exceedingly *_weird_* or what?
*AI Parrot Bot?*
Just the *FAX SONNY!*
*_ANSWER THE QUESTION LAD_*
*_Don't try intimating me boy._*
@@WilhelmKarsten far too broad ranging comment. the failure of the UK aircraft industry was mainly caused by poor decisions by the various governments, not excessive safety problems, would you fly on a 737 max?? thats a safety problem!!!
@@davedixon2068 It's a very honest and accurate comment, the folks that buy commercial jet aircraft don't watch fake news or biased media outlets...
British aircraft have a notoriously bad reputation for safety and reliability.
The UK aircraft industry was doomed after the country's defeat in WW2... the UK never recovered and was crippled by war debt, reparations and the loss of overseas territory.
I have, and certainly would fly on the 737 Max again, the Max has an excellent statistical safety record compared to the d-H Comet and even Concorde.
The Boeing 737 is the most successful aircraft in history with 15,000 sold, there are over 2,000 in the air as you read this, 1/3 of the people in the air right now are on board one, one takes-off or lands every 2 seconds.
Boeing has more orders now than it did in 2019.
Yeah it wasn’t the windows, it was the openings they fit in. Technicality.
Regardless it was a great looking airplane!
Wreckage recovered from the sea confirmed that the passenger windows were not related in any way with the catastrophic in-flight structural failures... the aluminum sheets are simply too thin and brittle and de Havilland did not design the fuselage strong enough to prevent cracks from joining up with adjacent panels
@@sandervanderkammen9230
@sandervanderkammen9230
Kharzeestan Krappenz DiktorBummer Jurkzxoffenz etc and co - they should all note good with much awestruckness & extreme wonderment.
*UPDATE MORE BREAKING NEWS ETC*
De Havilland (Of England) Comets were not grounded after 1970 due to structural problems.
*_It's interesting that some of the aircraft on the list should really have been noticeably safer than the Comet due to being a similar type but of much later design & manufacture but they definately were not safer._*
How things were back then -
*_Accident losses - % of aircraft built._*
DeHavilland Comet 4 UK 14%
DeHavilland Comet all mks 17%
Vickers VC10 UK 5%
*_The DH Comet had better safety than or similar safety to many other commercial passenger aircraft of a similar era_*
Douglas DC-1 99%
Douglas DC-2 47%
Douglas DC-3 30%
Douglas DC-4 26%
Boeing s300 72%
Boeing 307 70%
Boeing 247 48%
Boeing 707 20%
Lockheed L-049/149 Constellation 30%
Lockheed Electra Turboprop 29%
Fairchild FH-227 30%
McDonnell Douglas DC-8 14%
Sud Aviation Caravelle 15%
Canadair CL-44 Turboprop 46%
Convair CV-580 Turboprop 22%
A comparison of more recent aircraft.
Accident losses comparison examples.
1970s - 1980s
% of total Aircraft built
Similar aircraft type, date / decade, useage, size.
Biz Jets
BAe-125-800 1.7 %
Beechcraft Beechjet 400 2.2 %
Cessna 550 Citation II 7.1 %
Learjet 35 / 36 12 %
Beechcraft 1900 6%
Dassault Falcon 10 11.5%
Aérospatiale SN.601 22.5%
Medium size jets / Turboprops.
BAe-146 5.1%
Fokker 100 6%
McDonnell Douglas DC-9-30 9.5%
Fairchild FH-227 30%
McDonnell Douglas DC-8 14%
Canadair CL-44 Turboprop 46%
Convair CV-580 Turboprop 22%
Beechcraft, Fokker, McDonnell Douglass, Learjet, Fairchild, Aerospatiale, Canadair, Convair companies defunct.
All Comets, including some Comet 1s, had full civilian use certification at some point after 1954, civilian use certification only being withdrawn after commercial flying stopped. Examples were flying until 1997 - one example did a signals research global circumnavigation flight series in 1993 via Australia virtually without a rest travelling 28000 miles, only had an ice warning indicator issue during the flights.
*The DH Comet - World Firsts.*
1st gas turbine jet powered airliner. 1st high altitude 8psi pressurised full fuselage length passenger cabin airliner, not a trivial feature as structure strength required for pressurisation considerably exceeded strength required for normal flying stress. Nobody else had done anything similar before the Comet.
The b-47 used 2 relatively small, heavily built pressurised modules (the aircraft where 6 had their wings fold up in 2 months while flying & some had their wings fall off while parked).
The 1937 Boeing piston engined airliner pressurised passenger cabin was pressurised to 2 psi only - in fact that could easily be done as the normal unpressurized fuselage cabin structure strength for flying stresses only was all that was needed to be adequate so no significant weight increase issues needed addressing.
1st all hydraulically powered flying surface controls & actuators airliner with under carriage wheel disk brakes + ABS.
1st jet airliner to cross the Atlantic.
1st jet aircraft to do a world circumnavigation flights series.
*Of course De Havilland had prior experience building many all metal construction airframe aircraft including thousands of jet powered fighter aircraft that were primarily of metal construction with pressurised cockpits & jet engines built by De-Havilland & we know the world's first all metal construction airframe airliner was built in England in the 1920s by Handley Page.*
*_De Havilland did indeed always work to better than industry standards at the time, used up to date knowledge for the design & no evidence of negligence or criminal negligence was ever produced in relation to the DH Comet._*
The course of De Havilland & the general UK aerospace industry sector was not affected even slightly by the DH Comet.
*_Other interesting World firsts_*
_World's first turboprop aircraft._
*Vickers Viscount Turboprop Airliner 1947.*
*A 1945 Gloster Meteor Aircraft with Turboprop Gas Turbine Engine.*
They might like to answer these questions.
*Which airline has just ordered*
*60 RR England Trent XWB Engines*
*& What aircraft are the engines for?*
_Bonus question for 10 points._
Which country has the
*World's Highest Combined Per Capita*
*Nuclear + Defence + Aerospace Sector Activity?*
👍 & 🙂 & of course 😎 indeed.
*C H E E R S* & without doubt -
_Toodle_ -PIP- *Old* *_Chap._*
. .... . ... . ... .. .. .
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Ivcxivcxivcxcxixccv
ivxvivcxiccxxcc
When
_"Wreckage recovered from the sea confirmed that the passenger windows were not related in any way with the catastrophic in-flight structural failures"???._
*The windows shape & anything to do with hatches, doors & windows is relevant of course. The fact that wreckage from one aircraft incident or the water tank test fuselage showed a particular fracture route doesn't definately allow a particular conclusion regarding the window shape one way or the other.*
_"The explosive cabin rupture was along the crown of the fuselage where de Havilland had used aluminum skins that were thinner than the rest of the pressure cabin"??_
*The fuselage crown skin thickness relative to the rest of the fuselage skin is irrelevant & was not a cause of any incidents.*
_"AL2014B alloy is too brittle for the application"???_
*The particular alloys used passed all De Havilland's tests, the alloy used became unavailable as improved alloys had been developed which had nothing to do with the Comet.*
_"The Comet lacked proper rip-stop doubler joints and the fuselage reinforcement hoops were too weak and spaced too far apart to prevent cracks from joining up with adjacent panels"?_
*Obviously rip stop doublers were used, frames (hoops) were not too weak & frames (hoops) were not spaced too far apart.*
_"The riveting techniques were also found to be well below industry standards for pressurized cabins"??_
*De Havilland had extensive experience with all metal airframe aircraft construction. A protracted and extensive testing programme involving fuselage tests & other assemblies & component testing showed riveting techniques used were acceptable.*
_"A disturbing number of manufacturing defects were found on completed aircraft that had completely escaped QC inspection"?_
*De Havilland had extensive prior experience with all metal airframe aircraft construction. A protracted and extensive testing programme involving fuselage tests & other testing showed riveting techniques used & manufacturing & QC methods & procedures were acceptable. It is not the case that a disturbing number of defects were found on completed aircraft that had completely escaped QC inspection.*
. ......... .
xcvcxv
Which
Plastic,synthetic, composite aircraft will fail similar to deep sea submersibles. The people are willing experimental subjects for a price😮
Composite aircraft like the 787 and A350 Have a predetermined cycle life when the plane must be scrapped due to deterioration of the resins and fibers.
A well made Aluminum aircraft like the Boeing 707 series can have a potential unlimited service life with proper maintenance... the limiting factor here is cost.
2:23 South American or South African?
The Comet in the 1950's, the 737max in the 2020's. History does not repeat, but it rhymes.
The Comet Disaster is the worst engineering failure in commercial aviation history, the Comet 1 had a 46% loss rate and had its airworthiness certification permanently revoked.
By comparison the 737Max has an excellent safety record
@@WilhelmKarsten I made a lot of parts for the 737max. They aren't having problems because of anything I did.
@@Stacie45Boeing has more orders now than it did in 2019, apparently the folks that actually buy jet airliners know something that the news media clowns don't?
@@Begeye-bh5ux Statistical death rates for the 737 are excellent compared to the Comet.
@@Begeye-bh5ux You clearly have no idea what you are talking about... the Boeing 737 has an excellent safety record compared to other aircraft... this are facts, not fake news or biased media rhetoric.
The 737 is the most successful aircraft in history with over *15,000* sold, that's fifteen THOUSAND with 3 zeros.
There are more than 2,000 737s in the air right now, nearly 1/3 of all the people in the air right now are on board a 737.
One takes off and lands every 2 seconds!
Not mentioned is harmonic frequency vibrations caused by the new turbine engines. All structures have a natural nodal point at any given frequency. This is the same for a bridge or a helicopter. The AS 350 A Star has a weight installed under the front seat to move in the opposite direction of this node and cancel it out. It is my opinion that the natural node of the Comet airframe was where the window broke.
Interesting theory but not something supported by any credible evidence.
The Comet Disaster was the result of engineering incompetence and criminal negligence.
de Havilland use aluminum skins that were way too thin (just 1mm) and a alloy that was too brittle and weak.
The Comet was built without proper overlapping rip-stop doubler joints and the fuselage reinforcement hoops were too weak and spaced too far apart to prevent cracks from joining up with adjacent panels.
The rivet work was poor designed and installed with poor techniques and workmanship, quality control standards were inadequate.
de Havilland had precious little experience in building aircraft from riveted aluminum and was still producing jets with fuselages made from wood and linen fabric into the 1950s.
They made beautiful flying machines with wood and linen fabric. Wood is the original composite material. The only problem is lack of skilled craftsmen and slow construction time.
@thomashesselgrave6898 Wood lacks consistent strength and durability, it deteriorates rapidly in the elements...of the 7,000 Mosquitos de Havilland built not a single one remains flying in original condition today, most suffered irrepairable water and rot damage within just a few years of service and were scrapped.
The technology and techniques used to make wood planes do not translate into aluminum aircraft with pressurized cabins.
By 1954 de Havilland was decades behind in aircraft technology and never successfully transitioned to building modern aircraft.
@@sandervanderkammen9230
They should note & remember if they don't want to look like they haven't got a clue all over YT.
*In fact Dehavilland was making all metal airframe aircraft before the Comet.*
DH previously used what was in fact a lignin fibre reinforced composite using advanced adhesives & resins which are still produced for the aerospace industry.
A little unknown fact Boing was going to make the Comet under License named 737 Xbox.
Strange how deHavilland, after 30 years of making aircraft could have made this mistake.
de Havilland had a very poor reputation for safety and had appalling loss rates.
D-H simply had no experience building large, all-metal pressurized aircraft...they were still building planes primarily from wood and linen fabric well into the 1950s.
@@sandervanderkammen9230
@sandervanderkammen9230
Kharzeestan Krappenz DiktorBummer Jurkzxoffenz etc and co - they should all note good with much awestruckness & extreme wonderment.
*UPDATE MORE BREAKING NEWS ETC*
De Havilland (Of England) Comets were not grounded after 1970 due to structural problems.
*_It's interesting that some of the aircraft on the list should really have been noticeably safer than the Comet due to being a similar type but of much later design & manufacture but they definately were not safer._*
How things were back then -
*_Accident losses - % of aircraft built._*
DeHavilland Comet 4 UK 14%
DeHavilland Comet all mks 17%
Vickers VC10 UK 5%
*_The DH Comet had better safety than or similar safety to many other commercial passenger aircraft of a similar era_*
Douglas DC-1 99%
Douglas DC-2 47%
Douglas DC-3 30%
Douglas DC-4 26%
Boeing s300 72%
Boeing 307 70%
Boeing 247 48%
Boeing 707 20%
Lockheed L-049/149 Constellation 30%
Lockheed Electra Turboprop 29%
Fairchild FH-227 30%
McDonnell Douglas DC-8 14%
Sud Aviation Caravelle 15%
Canadair CL-44 Turboprop 46%
Convair CV-580 Turboprop 22%
A comparison of more recent aircraft.
Accident losses comparison examples.
1970s - 1980s
% of total Aircraft built
Similar aircraft type, date / decade, useage, size.
Biz Jets
BAe-125-800 1.7 %
Beechcraft Beechjet 400 2.2 %
Cessna 550 Citation II 7.1 %
Learjet 35 / 36 12 %
Beechcraft 1900 6%
Dassault Falcon 10 11.5%
Aérospatiale SN.601 22.5%
Medium size jets / Turboprops.
BAe-146 5.1%
Fokker 100 6%
McDonnell Douglas DC-9-30 9.5%
Fairchild FH-227 30%
McDonnell Douglas DC-8 14%
Canadair CL-44 Turboprop 46%
Convair CV-580 Turboprop 22%
Beechcraft, Fokker, McDonnell Douglass, Learjet, Fairchild, Aerospatiale, Canadair, Convair companies defunct.
All Comets, including some Comet 1s, had full civilian use certification at some point after 1954, civilian use certification only being withdrawn after commercial flying stopped. Examples were flying until 1997 - one example did a signals research global circumnavigation flight series in 1993 via Australia virtually without a rest travelling 28000 miles, only had an ice warning indicator issue during the flights.
*The DH Comet - World Firsts.*
1st gas turbine jet powered airliner. 1st high altitude 8psi pressurised full fuselage length passenger cabin airliner, not a trivial feature as structure strength required for pressurisation considerably exceeded strength required for normal flying stress. Nobody else had done anything similar before the Comet.
The b-47 used 2 relatively small, heavily built pressurised modules (the aircraft where 6 had their wings fold up in 2 months while flying & some had their wings fall off while parked).
The 1937 Boeing piston engined airliner pressurised passenger cabin was pressurised to 2 psi only - in fact that could easily be done as the normal unpressurized fuselage cabin structure strength for flying stresses only was all that was needed to be adequate so no significant weight increase issues needed addressing.
1st all hydraulically powered flying surface controls & actuators airliner with under carriage wheel disk brakes + ABS.
1st jet airliner to cross the Atlantic.
1st jet aircraft to do a world circumnavigation flights series.
*Of course De Havilland had prior experience building many all metal construction airframe aircraft including thousands of jet powered fighter aircraft that were primarily of metal construction with pressurised cockpits & jet engines built by De-Havilland & we know the world's first all metal construction airframe airliner was built in England in the 1920s by Handley Page.*
*_De Havilland did indeed always work to better than industry standards at the time, used up to date knowledge for the design & no evidence of negligence or criminal negligence was ever produced in relation to the DH Comet._*
The course of De Havilland & the general UK aerospace industry sector was not affected even slightly by the DH Comet.
*_Other interesting World firsts_*
_World's first turboprop aircraft._
*Vickers Viscount Turboprop Airliner 1947.*
*A 1945 Gloster Meteor Aircraft with Turboprop Gas Turbine Engine.*
They might like to answer these questions.
*Which airline has just ordered*
*60 RR England Trent XWB Engines*
*& What aircraft are the engines for?*
_Bonus question for 10 points._
Which country has the
*World's Highest Combined Per Capita*
*Nuclear + Defence + Aerospace Sector Activity?*
👍 & 🙂 & of course 😎 indeed.
Cheers.
_Toodle_ -PIP- *Old* *_Chap._*
. .... . ... . ... ..
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Ivcxivcxivcxcxii
vxvivcxiccxxcc
@@petemaly8950*Name a British jet aircraft in production today in the UK???*
@@sandervanderkammen9230
Muncherz Krappenz DiktorBummer KARZEESTAN Jurkzxoffenzstadt & co - they should all note with much awe and great reverence.
*****
*How come they can't answer simple questions - why is that?*
*****
*_DID SOMEBODY ACTUALLY SAY SOMEWHERE THAT THERE'S AIRLINER ASSEMBLY LINES OR SIMILAR IN THE UK OR IRELAND OR THAT Airbus or BOW-WING is actually British? (B-47 wings on many occasions folded up in flight or dropped off while parked)._*
Of course Brazil makes very good airliners & Brazil is 100th down list along with Indonesia for wealth per capita.
*Norway Holland Denmark Ireland Belgium - Top 20 wealth per capita - Don't make airliners - its as simple as that.*
BAe Systems & RR combined now do more Airbus work than Germany on an absolute basis & significantly more work than that on a per capita basis.
Per capita for the home nation BAe Systems is the world's largest defence contractor.
_BAe systems announced the recent £4 Billion takeover of Colorado based US based Ball Aerospace._
*BAE systems now does a significantly higher value of work for Airbus than it did when it was a major Airbus shareholder before 2005.*
*_RR now owns US Engine maker Allison for example which does classified Aerospace work for the US Govt._*
The UK has more important stuff to do these days.
_Routine simple passenger aircraft airframe assembly is becoming more of a 3rd world / trailer park area thing._
EG -
*_The DH Comet - world's first high altitude capable pressurised passenger cabin jet airliner in regular service, world's first jet airliner aircraft to cross the Atlantic, worlds first jet airliner aircraft to complete a global circumnavigation flight series._*
*They might try to sensibly answer this question - why do they believe that BAE Systems & RR (aero engines etc) & other companies, for example should be doing anything other than what they currently do & where do they get the idea from that the DH Comet had any affect at all on the progression UK aerospace sector.*
*Anybody currently flying on a widebody airliner stands a good chance of being on an aircraft powered by RR gas turbine aero engines built in England.*
📯📯📯📯
*The New RR Trent Ultrafan*
*Built In England*
*_World's Largest (see T&Cs)_*
*_Gas Turbine Aero Engine_*
📯📯📯📯
👍Manufactured by the people on a small island with less than 1% of the world's population.👍
*_A typical but small glimpse of what goes on in the very internationally orientated British aerospace sector._* -
Boeing Apache Attack Helicopter.
AH-64: *75 UK suppliers,* 7% UK content, global fleet of 1280+ aircraft.
*F35B more than 130 UK Suppliers, more than 30% UK content.*
*_F35A & F35C more than 130 UK Suppliers, more than 15% UK content._*
They might like to answer these questions.
*Which airline has just ordered*
*60 RR England Trent XWB Engines*
*& What aircraft are the engines for?*
_Bonus question for 10 extra points._
Which country has the
*World's Highest Combined Per Capita*
*Nuclear / Defence / Aerospace Sector Activity?*
👍 & 🙂 & of course 😎 indeed.
Cheers.
_Toodle_ -PIP- *Old* *_Chap._*
. ... . . ..... . . ...
. . ... . .....
ccicci vivvixx
ixxiccicci
@sandervanderkammen9230
*UPDATE MORE BREAKING NEWS ETC*
De Havilland (Of England) Comets / Nimrods were not grounded after 1970 due to structural problems.
Of course it should indeed be noted that as far as flying stresses are concerned the Comet & Nimrod had particularly robust airframes.
*_It's interesting that some of the aircraft on the list should really have been noticeably safer than the Comet due to being a similar type but of much later design & manufacture but they definately were not safer._*
How things were back then -
*_Accident losses - % of aircraft built._*
DeHavilland Comet 4 UK 14%
DeHavilland Comet all mks 17%
Vickers VC10 UK 5%
*_The DH Comet had better safety than or similar safety to many other commercial passenger aircraft of a similar era_*
Douglas DC-1 99%
Douglas DC-2 47%
Douglas DC-3 30%
Douglas DC-4 26%
Boeing s300 72%
Boeing 307 70%
Boeing 247 48%
Boeing 707 20%
Lockheed L-049/149 Constellation 30%
Lockheed Electra Turboprop 29%
Fairchild FH-227 30%
McDonnell Douglas DC-8 14%
Sud Aviation Caravelle 15%
Canadair CL-44 Turboprop 46%
Convair CV-580 Turboprop 22%
A comparison of more recent aircraft.
Accident losses comparison examples.
1970s - 1980s
% of total Aircraft built
Similar aircraft type, date / decade, useage, size.
Biz Jets
BAe-125-800 1.7 %
Beechcraft Beechjet 400 2.2 %
Cessna 550 Citation II 7.1 %
Learjet 35 / 36 12 %
Beechcraft 1900 6%
Dassault Falcon 10 11.5%
Aérospatiale SN.601 22.5%
Medium size jets / Turboprops.
BAe-146 5.1%
Fokker 100 6%
McDonnell Douglas DC-9-30 9.5%
Fairchild FH-227 30%
McDonnell Douglas DC-8 14%
Canadair CL-44 Turboprop 46%
Convair CV-580 Turboprop 22%
Beechcraft, Fokker, McDonnell Douglass, Learjet, Fairchild, Aerospatiale, Canadair, Convair companies defunct.
All Comets, including some Comet 1s, had full civilian use certification at some point after 1954, civilian use certification only being withdrawn after commercial flying stopped. Examples were flying until 1997 - one example did a signals research global circumnavigation flight series in 1993 via Australia virtually without a rest travelling 28000 miles, only had an ice warning indicator issue during the flights.
*The DH Comet - World Firsts.*
1st gas turbine jet powered airliner. 1st high altitude 8psi pressurised full fuselage length passenger cabin airliner, not a trivial feature as structure strength required for pressurisation considerably exceeded strength required for normal flying stress. Nobody else had done anything similar before the Comet.
The b-47 used 2 relatively small, heavily built pressurised modules (the aircraft where 6 had their wings fold up in 2 months while flying & some had their wings fall off while parked).
The 1937 Boeing piston engined airliner pressurised passenger cabin was pressurised to 2 psi only - in fact that could easily be done as the normal unpressurized fuselage cabin structure strength for flying stresses only was all that was needed to be adequate so no significant weight increase issues needed addressing.
1st all hydraulically powered flying surface controls & actuators airliner with under carriage wheel disk brakes + ABS.
1st jet airliner to cross the Atlantic.
1st jet aircraft to do a world circumnavigation flights series.
*Of course De Havilland had prior experience building many all metal construction airframe aircraft including thousands of jet powered fighter aircraft that were primarily of metal construction with pressurised cockpits & jet engines built by De-Havilland & we know the world's first all metal construction airframe airliner was built in England in the 1920s by Handley Page.*
*_De Havilland did indeed always work to better than industry standards at the time, used up to date knowledge for the design & no evidence of negligence or criminal negligence was ever produced in relation to the DH Comet._*
The course of De Havilland & the general UK aerospace industry sector was not affected even slightly by the DH Comet.
*_Other interesting World firsts_*
_World's first turboprop aircraft._
*Vickers Viscount Turboprop Airliner 1947.*
*A 1945 Gloster Meteor Aircraft with Turboprop Gas Turbine Engine.*
People might like to have a go at these questions.
*Which airline has just ordered*
*60 RR England Trent XWB Engines*
*& What aircraft are the engines for?*
_Bonus question for 10 points._
Which country has the
*World's Highest Combined Per Capita*
*Nuclear + Defence + Aerospace Sector Activity?*
👍 & 🙂 & of course 😎 indeed.
Cheers.
_Toodle_ -PIP- *Old* *_Chaps / Chapesses._*
. .... . ... . ... ..
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It was deHavilland himself on his deathbed that said he should've reduxed the windows.
Rivet-bond ally structures is not just commonplace on aircraft but is also being seen in the autoindustry, Lotus, Morgan, Jaguar, Land Rover.
More lies from British revisionist "historians"
The wreckage recovered from the sea confirmed that the passenger windows were not involved in the catastrophic in-flight structural failures.
The Comet Disaster is the result of gross engineering incompetence and criminal negligence it's the worst engineering failure in commercial aviation history
Chow Mein gobblers should be aware.
*_Accident losses - % of aircraft built._*
DeHavilland Comet 4 UK 14%
DeHavilland Comet all mks 17%
Vickers VC10 UK 5%
Boeing 707 USA *20%*
Lockheed Electra USA *29%*
Pile of sow exhaust innit?
😅☢️😅
I was on the last commercial flight of a Dan Air comet 4b and i still have the souvenir package that we were given that day.
You're very luck to be alive...
@@WilhelmKarsten probably but I think things had improved by the late 1970s
@@user-xh3lz9xt4lThe official story was Dan Air retired the Comet 4s due to an accute shortage of spare parts, which is true (parts between the Comet and Nimrod are not interchangeable) it was not made public until years later that Dan Air accelerated retirement of its fleet of Comets after premature fatigue damage was found in the wing spars of all the remaining aircraft.
@@WilhelmKarsten I was too young to know that but maybe better not to have known.
He says “South American Airways” the caption says South African Airways (2:26) 😂
The title adds to “clickbait”. Makes money for the You-Tuber.. Might as well state it was aluminum…
Metal fatigue and stress on the body- lessons learned the hard way! That’s life….
The real tragedy of the Comet Disaster was that it could have been easily prevented if de Havilland had simply followed well-known and understood industry standards for construction of pressurized cabins made from riveted aluminum alloys.
de Havilland simply lacked experience with these types of structures, in fact they were still making jet aircraft made primarily from wood and linen fabric at the time.
yet another "what if"
from history
Chow Mein gobblers should be aware.
*_Accident losses - % of aircraft built._*
DeHavilland Comet 4 UK 14%
DeHavilland Comet all mks 17%
Vickers VC10 UK 5%
Boeing 707 USA *20%*
Lockheed Electra USA *29%*
@@petemaly8950*Please name a single British company that still makes commercial jet aircraft in the UK?*
@@sandervanderkammen9230
*WHAT*
* Neuronally challenged infantile Chow Mein Munchers should note*
*_DID SOMEBODY SAY THERE'S AIRLINER ASSEMBLY LINES OR SIMILAR IN THE UK OR IRELAND?_*
😅😅👍😅😅
Notice they even reinforced the outside skin to cope with the probably windows corners failure. Don’t think glue was that great then , but don’t think glue would do would do. Temperature inside and outside big variation . Plus co efficient of expansion. Difference. Not compatible
Wreckage recovered from the sea confirmed that the passenger windows were not related in any way with the catastrophic in-flight structural failures.
de Havilland was negligent in using aluminum skins that were far too thin and an alloy that was too brittle.
The Comet lacked proper rip-stop doubler joints and the fuselage reinforcement hoops were too weak and spaced too far apart to prevent cracks from joining up with adjacent panels.
The design of the riveted fastners and the method of construction was inadequate and well below industry standards for pressurized cabins.
de Havilland installed thicker skins on the roof section but the Comet modification were not enough to make the aircraft safe and its airworthiness certificate was permanently revoked.
Sooooo.....it was the square windows.
The windows were not square or related in any way to the catastrophic in-flight structural failures.
@@WilhelmKarstentrue the windows arent square they are oblong, but the were involved in the break up of the aircraft listen to what is actually said
@@davedixon2068 They had the same 5 inch radius as modern aircraft.
The square windows theory is a red herring that de Havilland put forward well before anyone knew the actual cause of the catastrophic in-flight structural failures.
Later, when wreckage recovered from the sea confirmed that the windows were not involved, it was a combination of engineering incompetence and criminal negligence.
De Havilland had used aluminum skins that were too thin and made from an alloy that was too brittle, the rivets were poorly designed and installed. The Comet lacked proper Rip-stop doubler joints and the fuselage frame hoops were too narrow and spaced to far apart to prevent cracks from joining up with adjacent panels.
Improper testing allowed these fatal flaws to enter service.
*Krapper & co 😅😅😅👍🇮🇪*
🇨🇳 Have they had chicken chow mein for dinner today🇨🇳?
*They might like to try reading the questions & attempt a coherent reply in glorious victorious ENGLISH. THE WORLDS MOST WIDELY SPOKEN VICTORIOUS GLoRIOUS PEOPLE'S INTERNATIONAL LANGUAGE & THE MANDATORY VICTORIOUS GLoRIOUS PEOPLE'S COMMERCIAL AVIATION LANGUAGE.*
*Wrong Answer.*
They might like to memorize.
*_More than 33,000 Whittle style centrifugal compressor internal combustion gas turbine aircraft engines have been produced, from the time Whittle demonstrated his aircraft engine for the first time in the world, to the present date._*
*How many fixed wing & rotating wing aircraft types have used the Whittle Gas turbine aircraft engine including reverse flow combuster type engines?*
Also, if they would like to discuss inventions, the gas turbine was invented in the people's republic of glorious England before the 1800s. Which glorious & infinitely superior & always victorious English person invented the gas turbine engine before 1800?
*_DON'T TRY INTIMATING ME SONNY?_*
*JUST THE FAX HERE BOY*
@@Paul-Nicer58 *Please name a single British company that still makes British jet aircraft in the UK???*
It was the two combined 🙄 Two videos on my channel hypothesize the chance MH370 successfully ditched in the southern Indian Ocean. Let me know what you think 👍
Clearly it was, and this was stated at the end. Don't bother watching.
Wreckage recovered from the sea confirmed that the passenger windows were not related in any way with the catastrophic in-flight structural failures.
Subsequent investigations revealed that the aluminum sheets on the roof were far too thin and weak and the AL2014B alloy was too brittle.
The Comet lacked proper overlapping rip-stop doubler joints and the fuselage reinforcement hoops were too weak and spaced too far apart to prevent cracks from joining up with adjacent panels.
The use of die cut holes and press form rivets was completely inappropriate and well below industry standards.
An appalling number of manufacturing defects were found on completed aircraft and the quality control standards were very poor.
@@sandervanderkammen9230
Kharzeestan Krappenz DiktorBummer Jurkzxoffenz etc and co - they should all note good with much awestruckness & extreme wonderment.
*UPDATE MORE BREAKING NEWS ETC*
De Havilland (Of England) Comets were not grounded after 1970 due to structural problems.
*_It's interesting that some of the aircraft on the list should really have been noticeably safer than the Comet due to being a similar type but of much later design & manufacture but they definately were not safer._*
How things were back then -
*_Accident losses - % of aircraft built._*
DeHavilland Comet 4 UK 14%
DeHavilland Comet all mks 17%
Vickers VC10 UK 5%
*_The DH Comet had better safety than or similar safety to many other commercial passenger aircraft of a similar era_*
Douglas DC-1 99%
Douglas DC-2 47%
Douglas DC-3 30%
Douglas DC-4 26%
Boeing s300 72%
Boeing 307 70%
Boeing 247 48%
Boeing 707 20%
Lockheed L-049/149 Constellation 30%
Lockheed Electra Turboprop 29%
Fairchild FH-227 30%
McDonnell Douglas DC-8 14%
Sud Aviation Caravelle 15%
Canadair CL-44 Turboprop 46%
Convair CV-580 Turboprop 22%
A comparison of more recent aircraft.
Accident losses comparison examples.
1970s - 1980s
% of total Aircraft built
Similar aircraft type, date / decade, useage, size.
Biz Jets
BAe-125-800 1.7 %
Beechcraft Beechjet 400 2.2 %
Cessna 550 Citation II 7.1 %
Learjet 35 / 36 12 %
Beechcraft 1900 6%
Dassault Falcon 10 11.5%
Aérospatiale SN.601 22.5%
Medium size jets / Turboprops.
BAe-146 5.1%
Fokker 100 6%
McDonnell Douglas DC-9-30 9.5%
Fairchild FH-227 30%
McDonnell Douglas DC-8 14%
Canadair CL-44 Turboprop 46%
Convair CV-580 Turboprop 22%
Beechcraft, Fokker, McDonnell Douglass, Learjet, Fairchild, Aerospatiale, Canadair, Convair companies defunct.
All Comets, including some Comet 1s, had full civilian use certification at some point after 1954, civilian use certification only being withdrawn after commercial flying stopped. Examples were flying until 1997 - one example did a signals research global circumnavigation flight series in 1993 via Australia virtually without a rest travelling 28000 miles, only had an ice warning indicator issue during the flights.
*The DH Comet - World Firsts.*
1st gas turbine jet powered airliner. 1st high altitude 8psi pressurised full fuselage length passenger cabin airliner, not a trivial feature as structure strength required for pressurisation considerably exceeded strength required for normal flying stress. Nobody else had done anything similar before the Comet.
The b-47 used 2 relatively small, heavily built pressurised modules (the aircraft where 6 had their wings fold up in 2 months while flying & some had their wings fall off while parked).
The 1937 Boeing piston engined airliner pressurised passenger cabin was pressurised to 2 psi only - in fact that could easily be done as the normal unpressurized fuselage cabin structure strength for flying stresses only was all that was needed to be adequate so no significant weight increase issues needed addressing.
1st all hydraulically powered flying surface controls & actuators airliner with under carriage wheel disk brakes + ABS.
1st jet airliner to cross the Atlantic.
1st jet aircraft to do a world circumnavigation flights series.
*Of course De Havilland had prior experience building many all metal construction airframe aircraft including thousands of jet powered fighter aircraft that were primarily of metal construction with pressurised cockpits & jet engines built by De-Havilland & we know the world's first all metal construction airframe airliner was built in England in the 1920s by Handley Page.*
*_De Havilland did indeed always work to better than industry standards at the time, used up to date knowledge for the design & no evidence of negligence or criminal negligence was ever produced in relation to the DH Comet._*
The course of De Havilland & the general UK aerospace industry sector was not affected even slightly by the DH Comet.
*_Other interesting World firsts_*
_World's first turboprop aircraft._
*Vickers Viscount Turboprop Airliner 1947.*
*A 1945 Gloster Meteor Aircraft with Turboprop Gas Turbine Engine.*
They might like to answer these questions.
*Which airline has just ordered*
*60 RR England Trent XWB Engines*
*& What aircraft are the engines for?*
_Bonus question for 10 points._
Which country has the
*World's Highest Combined Per Capita*
*Nuclear + Defence + Aerospace Sector Activity?*
👍 & 🙂 & of course 😎 indeed.
Cheers.
_Toodle_ -PIP- *Old* *_Chap._*
. .... . ... . ... .. ... ..
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@@sandervanderkammen9230
_"Wreckage recovered from the sea confirmed that the passenger windows were not related in any way with the catastrophic in-flight structural failures"???._
*The windows shape & anything to do with hatches, doors & windows is relevant of course. The fact that wreckage from one aircraft incident or the water tank test fuselage showed a particular fracture route doesn't definately allow a particular conclusion regarding the window shape one way or the other.*
_"The explosive cabin rupture was along the crown of the fuselage where de Havilland had used aluminum skins that were thinner than the rest of the pressure cabin"??_
*The fuselage crown skin thickness relative to the rest of the fuselage skin is irrelevant & was not a cause of any incidents.*
_"AL2014B alloy is too brittle for the application"???_
*The particular alloys used passed all De Havilland's tests, the alloy used became unavailable as improved alloys had been developed which had nothing to do with the Comet.*
_"The Comet lacked proper rip-stop doubler joints and the fuselage reinforcement hoops were too weak and spaced too far apart to prevent cracks from joining up with adjacent panels"?_
*Obviously rip stop doublers were used, frames (hoops) were not too weak & frames (hoops) were not spaced too far apart.*
_"The riveting techniques were also found to be well below industry standards for pressurized cabins"??_
*De Havilland had extensive experience with all metal airframe aircraft construction. A protracted and extensive testing programme involving fuselage tests & other assemblies & component testing showed riveting techniques used were acceptable.*
_"A disturbing number of manufacturing defects were found on completed aircraft that had completely escaped QC inspection"?_
*De Havilland had extensive prior experience with all metal airframe aircraft construction. A protracted and extensive testing programme involving fuselage tests & other testing showed riveting techniques used & manufacturing & QC methods & procedures were acceptable. It is not the case that a disturbing number of defects were found on completed aircraft that had completely escaped QC inspection.*
I might be wrong on this but I thought that the Comet was being pressurized to 1 atmosphere, about 14 psi, so a much higher pressure than later airliners using about 8 to 9 psi. If outside air pressure is 4.3psi at 30,000 ft, then pressuring the cabin to around 1 atmosphere would be doubling the stress in the fuselage structure compared with modern airliners.
That is incorrect, the de Havilland Comet was only pressurized to a maximum 7.25 psi. Lower than some aircraft already in service at the time.
The Comet Disaster is the direct result of poor design and construction.
de Havilland simply used aluminum skins that were too thin (just 1mm) and used an alloy that was too brittle (AL2014B)
The Comet lacked proper Rip-stop doubler joints that were already industry standard and had fuselage frame hoops and stringers that were too weak to prevent cracks from joining up with adjacent panels
2:15
@@Paul-mh9prMaximum cabin pressure differential for the Comet was 7.25 psi..
Boeing had aircraft with a 9.8 psi rating before the Comet
@@WilhelmKarsten
They might like to stop talking gibberish & provide sources for the various ridiculous claims they keep repeating parrot fashion might they not.
Anyway.
A Comparison - for an idea of how things were back then.
Lockheed Electra
US.
First flew 1957
First US turboprop airliner
4 engine turboprop.
Pressurised passenger cabin.
Three aircraft were lost in fatal accidents between February 1959 and March 1960. After the third crash, the FAA limited the Electra's speed until the cause could be determined.[7] After an extensive investigation, two of the crashes (in September 1959 and March 1960) were found to be caused by an engine-mount problem. The mounting of the gearbox cracked, and the reduced rigidity enabled a phenomenon called "whirl mode flutter"
Could cause wing destruction.
The three aircraft accidents did not result in the type being grounded.
Vickers Viscount.
UK.
First flew 1948, 10 years before the Electra.
4 engine turboprop.
RR Dart engines.
Pressurised passenger cabin.
@Peppa_Wiggles2 *The de Havilland Comet has the worst safety record of any jet airliner in history.*
*46% aircraft loss rate*
But the metal fatigue did start around the window in the top of the fuselage for radio communications
But it's not the cause of the catastrophic in-flight structural failures, the fatal flaws were the insufficient thickness and strength of the aluminum skins that were made from an alloy that was too brittle, badly designed and installed riveted fasteners, a lack of proper overlapping Rip-stop doubler joints and the fuselage frame hoops were too narrow and spaced to far apart to prevent cracks from joining up with adjacent panels.
Chow Mein gobblers should be aware.
*_Accident losses - % of aircraft built._*
DeHavilland Comet 4 UK 14%
DeHavilland Comet all mks 17%
Vickers VC10 UK 5%
Boeing 707 USA *20%*
Lockheed Electra USA *29%*
@@WilhelmKarsten
😂😂😂😂😂😂
@@petemaly8950 Comet 1 has a 46% loss rate
@@WilhelmKarsten
@sandervanderkammen9230
Kharzeestan Krappenz DiktorBummer Jurkzxoffenz etc and co - they should all note good with much awestruckness & extreme wonderment.
*UPDATE MORE BREAKING NEWS ETC*
De Havilland (Of England) Comets were not grounded after 1970 due to structural problems.
*_It's interesting that some of the aircraft on the list should really have been noticeably safer than the Comet due to being a similar type but of much later design & manufacture but they definately were not safer._*
How things were back then -
*_Accident losses - % of aircraft built._*
DeHavilland Comet 4 UK 14%
DeHavilland Comet all mks 17%
Vickers VC10 UK 5%
*_The DH Comet had better safety than or similar safety to many other commercial passenger aircraft of a similar era_*
Douglas DC-1 99%
Douglas DC-2 47%
Douglas DC-3 30%
Douglas DC-4 26%
Boeing s300 72%
Boeing 307 70%
Boeing 247 48%
Boeing 707 20%
Lockheed L-049/149 Constellation 30%
Lockheed Electra Turboprop 29%
Fairchild FH-227 30%
McDonnell Douglas DC-8 14%
Sud Aviation Caravelle 15%
Canadair CL-44 Turboprop 46%
Convair CV-580 Turboprop 22%
A comparison of more recent aircraft.
Accident losses comparison examples.
1970s - 1980s
% of total Aircraft built
Similar aircraft type, date / decade, useage, size.
Biz Jets
BAe-125-800 1.7 %
Beechcraft Beechjet 400 2.2 %
Cessna 550 Citation II 7.1 %
Learjet 35 / 36 12 %
Beechcraft 1900 6%
Dassault Falcon 10 11.5%
Aérospatiale SN.601 22.5%
Medium size jets / Turboprops.
BAe-146 5.1%
Fokker 100 6%
McDonnell Douglas DC-9-30 9.5%
Fairchild FH-227 30%
McDonnell Douglas DC-8 14%
Canadair CL-44 Turboprop 46%
Convair CV-580 Turboprop 22%
Beechcraft, Fokker, McDonnell Douglass, Learjet, Fairchild, Aerospatiale, Canadair, Convair companies defunct.
All Comets, including some Comet 1s, had full civilian use certification at some point after 1954, civilian use certification only being withdrawn after commercial flying stopped. Examples were flying until 1997 - one example did a signals research global circumnavigation flight series in 1993 via Australia virtually without a rest travelling 28000 miles, only had an ice warning indicator issue during the flights.
*The DH Comet - World Firsts.*
1st gas turbine jet powered airliner. 1st high altitude 8psi pressurised full fuselage length passenger cabin airliner, not a trivial feature as structure strength required for pressurisation considerably exceeded strength required for normal flying stress. Nobody else had done anything similar before the Comet.
The b-47 used 2 relatively small, heavily built pressurised modules (the aircraft where 6 had their wings fold up in 2 months while flying & some had their wings fall off while parked).
The 1937 Boeing piston engined airliner pressurised passenger cabin was pressurised to 2 psi only - in fact that could easily be done as the normal unpressurized fuselage cabin structure strength for flying stresses only was all that was needed to be adequate so no significant weight increase issues needed addressing.
1st all hydraulically powered flying surface controls & actuators airliner with under carriage wheel disk brakes + ABS.
1st jet airliner to cross the Atlantic.
1st jet aircraft to do a world circumnavigation flights series.
*Of course De Havilland had prior experience building many all metal construction airframe aircraft including thousands of jet powered fighter aircraft that were primarily of metal construction with pressurised cockpits & jet engines built by De-Havilland & we know the world's first all metal construction airframe airliner was built in England in the 1920s by Handley Page.*
*_De Havilland did indeed always work to better than industry standards at the time, used up to date knowledge for the design & no evidence of negligence or criminal negligence was ever produced in relation to the DH Comet._*
The course of De Havilland & the general UK aerospace industry sector was not affected even slightly by the DH Comet.
*_Other interesting World firsts_*
_World's first turboprop aircraft._
*Vickers Viscount Turboprop Airliner 1947.*
*A 1945 Gloster Meteor Aircraft with Turboprop Gas Turbine Engine.*
They might like to answer these questions.
*Which airline has just ordered*
*60 RR England Trent XWB Engines*
*& What aircraft are the engines for?*
_Bonus question for 10 points._
Which country has the
*World's Highest Combined Per Capita*
*Nuclear + Defence + Aerospace Sector Activity?*
👍 & 🙂 & of course 😎 indeed.
*C H E E R S* & without doubt -
_Toodle_ -PIP- *Old* *_Chap._*
. .... . ... . ... ..
... .... ... ....
Ivcxivcxivcxcxiivxvi
vcxiccxxcccxcxccx
Of course
Right. It was the fatigue test using a pre static tested fuselage which gave a rediculus long life whis was misleading
The subsequent investigations found over 100 fatal design flaws in the Comet 1 and it's airworthiness certificate was permanently revoked.
de Havilland was forced to do a complete redesign of the aircraft to meet safety requirements, Comet 4 is a completely new aircraft from nose to tail.
@@sandervanderkammen9230
Vickers Viscount 1st in the world Turboprop Pressurised Passenger Cabin Metal Construction Airliner flew 10 years before the Lockheed Electra Turboprop. The Viscount had a better safety record.
The Boeing 707 & Lockheed Electra had significantly *_worse safety numbers_* than the DH Comet.
Karzeestan / vindurrkrapper
*Probably* exceedingly *_weird_* or what?
*AI Parrot Bot?*
Just the *FAX SONNY!*
*_ANSWER THE QUESTION LAD_*
@@Paul-mh9prPlease name a single British company that still makes British jet aircraft in the UK?
@@WilhelmKarsten The British civil aircraft industry couldn't survive on its own making complete planes. Instead, they took a 20% stake in Airbus (since sold). Every civil Airbus wing is made in Britain. Rolls Royce builds large turbofan engines and is competitive with the American companies. If you are after complete jet aircraft. BAe builds Typhoon fighters.
@@garethonthetube That is completely false, most Airbus wings are not made in the UK, production was slashed after the cancelation of the A380, 340 and the passing of brexit.
Eurofighter Jagdflugzeug GmbH. Is not a British company, it's headquarters and main manufacturing facilities are in Germany.
GE-Safran is the largest manufacturer of jet engines in the world.
Please name a single British company that still makes British jet aircraft in the UK?
I us to fly on the comet 4 from London to Doha 1961
You're very lucky to be alive, the Comet has the highest loss rate and fatalities statistics of any jet airliner in history
@@Paul-mh9pr The Boeing 787 Dreamliner is the safest aircraft in the world.
Zero hull losses and Zero fatalities.
The Comet is the worst jet airliner in history and has the highest loss rate and fatalities statistics of any jet airliner
@@WilhelmKarsten
@WilhelmKarsten
One of the worst disasters was the 737 max for the most people killed per flight in a short space of time. due to design defects especially given that it was built by a company that had 60 years of experience for the aircraft type so no excuses! An aircraft that flew itself into the ground entirely automatically! Two times!
@@Paul-mh9pr The Boeing 737 Max has a much better safety record than the de Havilland Comet.
@@Paul-mh9pr The Boeing 737 Max has more orders now than it did in 2019.
The Boeing 737 is the most successful aircraft in history.
One third of all people in the air are on board a 737, one takes off or lands every 6 seconds there are 1,000 in the air at any time.
The Boeing 737 has flown more than 127 BILLION MILES.
Carried more than 19 BILLION passengers
No. This is a common misconception. The square windows were NOT the cause of the fatigue fracture although once started the fracture took the path of least resistance which was along the fuselage. In fact, wreckage recovered from one crash indicated the crack bypassed the windows altogether. No, the actual cause of the failure was due to the radome. It wasn't even a fault of the original design which was entirely adequate. Rather, the radome was increased in size when it was discovered the original apparatus and the attendant cut-out were inadequate. The opening was enlarged but additional reinforcement of the opening was skipped. In all cases, the point of origin of the crack was the radome. The split typically moved downwards to the door and then along the fuselage. We actually identified the point of origin early in the investigation but the revelation was met with incredulity and the water tank tests went ahead.
When the crack reached the door frame, it wouldn't have mattered what shape the windows were - the fuselage was certain to be torn apart by aerodynamic forces.
The water tank tests were instructional but we knew before we started what we'd find - to be honest the test was almost entirely redundant from a causal perspective. However it did provide a huge amount of information about airframe pressure cycles which was shared with the Americans. As it turned out, the 707 fuselage design benefited directly from this information as there were quite a few surprises for the engineers!
Round windows are used primarily because they are cheaper to manufacture and require less reinforcement. The Comet was reintroduced with the 4c which was, ironically, over-engineered. But by then the damage was done -t he Comet 4c was heavy, inefficient (cost-wise) and was capable of carrying only around 80 passengers. Sadly, the Comet 4c marked the beginning of the end for the British aviation industry which has since declined to zero. The Comet went on to become the Nimrod which was a fantastic maritime aircraft used for submarine hunting (amongst its many roles). The Nimrod also went to a (slightly) early demise due to being ruined by shoddy modifications and absurd government edicts.
I will be dead soon enough, and as such it is sad that knowledge of what actually happened will be lost, and an entirely false narrative will be the Comet's legacy.
The catastrophic in-flight structural failures were the direct result of engineering incompetence and criminal negligence.
That's a completely false myth, the Boeing 707 flew on July 15th 1954, before anyone including de Haviland knew what caused the catastrophic in-flight structural failures.
Nothing was learned from the Comet Disaster, it was a completely preventable tragedy.
@@WilhelmKarsten I can't take you seriously. Your level of knowledge is dismal
@@davidgapp1457 Spare us the British revisionist propaganda myths.
The Comet Disaster is the worst engineering failure in commercial jet aviation history.
FACT: de Havilland had very little experience with riveted aluminum airframe design and construction or pressurized cabins.
FACT: pressurized cabins had been around for 2 decades before the Comet Disaster.
FACT: de Havilland used aluminum skins that were too thin, Just 1mm thick on the crown of the passenger cabin where the fuselage catastrophically failed in-flight.
FACT: de Havilland used the wrong material, AL2014B is too brittle and completely unsuitable for pressure cabin skins.
FACT: de Havilland did not use overlapping Rip-stop doubler joints that were industry standard at the time.
FACT: the Comets fuselage frame hoops were too narrow and spaced too far apart to prevent cracks from joining up with adjacent panels.
FACT: de Havilland used inferior riveting techniques and riveted fasteners were poor quality with inadequate QC standards.
The rivet work on the Comet 1 was appallingly bad.
Any questions lad?
JUNKERS invented pressurized cabins made from riveted metal in 1931.
The Ju-86 was flying pressurized to over 52,000 feet during WW2.
Boeing built the first pressurized airliner in 1938 and by 1954 was the world's leader in pressurized aircraft.
The Royal Aircraft Establishment and de Havilland received data on metal fatigue in pressurized cabins from the B-29 program during WW2, unfortunately de Havilland only made aircraft from wood and fabric at the time and ignored this valuable data.
The real tragedy of the Comet Disaster was that it could have been easily prevented if de Haviland had simply followed well-known and understood industry standards for the design and construction of pressurized cabins made from riveted aluminum alloys.
The only lesson learned from the Comet Disaster was that the stakes had become too high to allow manufacturers to conduct their own crash investigations... de Havillands handling of the Comet investigations was reprehensible and amounts to a criminal act.
The Comet 1 had a staggering 46% loss rate, the worst jet airliner in history.
@WilhelmKarsten
Chicken Chow mein is nice Kharzeestan?
Bs by the way, total 😂
Comet all Mks loss rate 17%
*_Comet 4 loss rate 14%_*
Boeing 707 loss rate 20%
Lockheed Electra 29%
Vickers VC10 5%
@@Paul-Nicer58*Please name a single British company that still makes British jet aircraft in the UK????*
@@sandervanderkammen9230
*WHAT*
*Chow Mein Munchers should note*
*_DID SOMEBODY SAY THERE WAS ANY AIRLINER ASSEMBLY LINES OR SIMILAR IN THE UK OR IRELAND?_*
😅😅👍😅😅
@@Peppa_Wiggles23*Airbus SE and Spirit Aerosystems are not British companies.*
*WHAT*
* Neuronally challenged Chow Mein Munchers should note*
*_DID SOMEBODY SAY THERE'S AIRLINER ASSEMBLY LINES OR SIMILAR IN THE UK OR IRELAND?_*
😅😅👍😅😅
They didn’t help
Total red herring, wreckage recovered from the sea confirmed that the passenger windows were not related in any way with the catastrophic in-flight structural failures
Boeing would have jealous.
Why would Boeing be jealous?
😂Vickers Viscount 1st in the world Turboprop Pressurised Passenger Cabin Metal Construction Airliner flew 10 years before the Lockheed Electra Turboprop. The Viscount had a better safety record.
The Boeing 707 & Lockheed Electra had significantly worse safety numbers than the DH Comet.
No evidence of Dehavilland negligence or criminality or not working to better than industry standards at the time exists.
Karzeestan / vindurrkrapper
*Probably* exceedingly *_weird_* or what?
*AI Parrot Bot?*
Just the *FAX SONNY!*
*_ANSWER THE QUESTION LAD_*
*_Don't try intimating me boy._*
@@Paul-mh9pr *hi peppa Wiggles!* *Please name a single British company that still makes British jet aircraft in the UK???*
Members of our Royal Family including the late Queen are survivors of Comet 1 flights. How many others?
496 did not survive their flight on Comet... Comet 1 has a 46% loss rate... the worst safety record of any jet airliner.
@@sandervanderkammen9230@sandervanderkammen9230 😂Vickers Viscount 1st in the world Turboprop Pressurised Passenger Cabin Metal Construction Airliner flew 10 years before the Lockheed Electra Turboprop. The Viscount had a better safety record.
The Boeing 707 & Lockheed Electra had significantly worse safety numbers than the DH Comet.
No evidence of Dehavilland negligence or criminality or not working to better than industry standards at the time exists.
Karzeestan / vindurrkrapper
*Probably* exceedingly *_weird_* or what?
*AI Parrot Bot?*
Just the *FAX SONNY!*
*_ANSWER THE QUESTION LAD_*
*_Don't try intimating me boy._*
@@Paul-mh9pr *HI Peppa Wiggles!*
*PLEASE NAME A SINGLE BRITISH COMPANY THAT STILL MAKES BRITISH JET AIRCRAFT IN THE UK?*
@@sandervanderkammen9230
@WilhelmKarsten
*_Accident losses - % of aircraft built._*
DeHavilland Comet 4 UK 14%
DeHavilland Comet all mks 17%
Vickers VC10 UK 5%
Boeing 707 USA *20%*
Lockheed Electra USA *29%*
@@petemaly8950 *Please name a single British company that still makes British jet aircraft in the UK???*
Should have known better. The same thing happened to liberty ships during world war 2. Square hatches on decks led to ships breaking up under stress. Once rounded corners were used, the problem was cured. Maybe the US didnt make the facts available to the UK.
Actually both de Havilland and the Royal Aircraft Establishment received technical data on metal fatigue in pressurized cabins from the Boeing B-29 program during WW2.
The real tragedy of the Comet Disaster was that it could have been easily prevented if de Havilland had simply followed well-known and understood industry standards for construction of pressurized cabins made from riveted aluminum.
Another great british design
you are not convincing. seems the comedy of errors added up at the point of most likely failure, the square corners on the windows.
Wreckage recovered from the sea later confirmed that the passenger windows were not involved in the catastrophic in-flight structural failures.
de Havilland used aluminum skins that were too thin (just 1mm thick) and a aluminum alloy that was too brittle (AL2014B is not used for skins)
The Comet lacked proper Rip-stop doubler joints and the fuselage frame hoops were too narrow and spaced to far apart to prevent cracks from joining up with adjacent panels.
de Havillands calculations of the fuselage strength and its testing was all completely wrong... as was their theory of what caused the catastrophic failures.
Outside experts and consultants all agreed the it was not the shape of the passenger windows but de Havilland stuck with thier story and the media ran with it, it's a false urban myth that refuses to die.
@@WilhelmKarsten
DH was designing from first principles & building jet engines at the time.
The Comet was one of the most advanced passenger aircraft being built at the time.
The design & construction was essentially ok & one of the aircraft that crashed showed evidence of having a number of manufacturing faults involving the antenna hatch assembly which somehow ended up being used when it should have been scrapped.
The type of riveting used was to industry standard practice at the time.
@@Paul-mh9pr The de Havilland company was decades behind in aircraft technology.
The Comet Disaster was the direct result of Neolithic incompetence and criminal negligence
@@Paul-mh9pr d-H was decades behind in aircraft technology and the real tragedy of the Comet Disaster was that it could have been easily prevented if de Haviland had simply followed well-known and understood industry standards for the design and construction of pressurized cabins made from riveted aluminum alloys.
The Comet Disaster is the result of gross engineering incompetence and criminal negligence.
A truly shameful and humiliating chapter in British aviation history
@@WilhelmKarsten
Got any links to sources for those ridiculous claims.
It's obvious that DH were of course world leaders at the time makeing the first & most advanced all metal, pressurised cabin, jet powered, high altitude, passenger airliner in the world. They were also designing jet engines from first principles & building them.
All manufacturing was better than industry standards at the time including riveting & for example the adhesives developed & used are still today manufactured for use in the aerospace industry.
During the 1950s there were obviously aircraft with worse safety performances, it goes without saying.
Must say , those rivet work around the window frames looked pretty crude - Yikes !
The riveted fasteners were extremely poor on Comet, de Havilland experience building aircraft was primarily using wood and fabric
@@WilhelmKarsten
@WilhelmKarsten
Wrong. You are presenting an entirely false picture.
The 707 was not a safe aircraft & was not the first jet airliner.
You are presenting an entirely false picture.
The riveting methods used at the time were industry standard or better
The Comet simply attracted a lot of attention due to its highly advanced design & construction. DH was designing jet engine from first principles & building them.
DH used the most advanced design & construction techniques & processes anywhere in the world at the time.
The Comet was not built from plywood, chipboard & pva wood glue from the DIY store. In fact the highly advanced adhesives actually used are still currently manufactured & used in the aerospace industry.
Changes made to the aircraft were simply mostly to look like something was being done &:most changes were changes that would have been actioned regardless & many changes were carried out just in case. The original design & construction were good. There were problems but at the time that was expected.
The most significant changes were more powerful engines & pointing the engine exhausts away from the fuselage.
There was never a complete redesign.
The Comet simply attracted a lot of attention due to its highly advanced design & construction. DH was designing jet engine from first principles & building them.
DH used the most advanced design & construction techniques & processes anywhere in the world at the time.
The Comet was not built from plywood, chipboard & pva wood glue from the DIY store. In fact the highly advanced adhesives actually used are still currently manufactured & used in the aerospace industry.
Changes made to the aircraft were simply mostly to look like something was being done &:most changes were changes that would have been actioned regardless & many changes were carried out just in case. The original design & construction were good. There were problems but at the time that was expected.
The most significant changes were more powerful engines & pointing the engine exhausts away from the fuselage.
There was never a complete redesign.
@@Paul-mh9pr de Haviland was decades behind in aircraft technology and the real tragedy of the Comet Disaster was that it could have been easily prevented if de Haviland had simply followed well-known and understood industry standards for the design and construction of pressurized cabins made from riveted aluminum alloys.
The Comet Disaster is the result of gross engineering incompetence and criminal negligence.
A truly shameful and humiliating chapter in British aviation history
@@Paul-mh9prThe facts are irrefutable, the Comet Disaster is the worst engineering failure in commercial aviation history and is the result of gross engineering incompetence and criminal negligence
@@WilhelmKarsten
Provide evidence with links to sources that the DH Comet was not the most advanced high altitude pressurised passenger cabin jet airliner in the world at the time using design methods & construction methods & materials that were always better than industry standard. Including the design & materials selection for upholstery, toilet roll holders, light switches, curtains, partitions, bulkheads, pressure bulkheads, door handles, plumbing pipes & magazine holders.
Also provide evidence with links to sources that DH were guilty of criminal negligence.
Comparison - for an idea of how things were back then -
Lockheed Electra
US.
First flew 1957 10 years after the Viscount.
First US turboprop airliner
4 engine turboprop.
Pressurised passenger cabin.
Of the total of 170 Electras built, as of June 2011, 58 have been written off because of crashes and other accidents.
29% of aircraft in hull loss accidents.
6 fatalities per aircraft.
Hull-losses: 59
Hull-loss accidents: 49
with a total of 1037 fatalities
Criminal occurences (hull-losses ): 1
with a total of 0 fatalities
Hijackings: 6
with a total of 1 fatalities
Survival rate:
12.0% of all occupants survived fatal accidents.
Three aircraft were lost in fatal accidents between February 1959 and March 1960. After the third crash, the FAA limited the Electra's speed until the cause could be determined.[7] After an extensive investigation, two of the crashes (in September 1959 and March 1960) were found to be caused by an engine-mount problem. The mounting of the gearbox cracked, and the reduced rigidity enabled a phenomenon called "whirl mode flutter"
Could cause wing destruction.
The three aircraft accidents did not result in the type being grounded for some unfathomable reason, odd isn't it?
Vickers Viscount.
UK.
First flew 1948 10 years before the Electra.
4 engine turboprop.
RR Dart engines.
Pressurised passenger cabin.
All 707s that were doing full time airline service are now scrapped or in museums. The only aircraft still flight worthy are those that were military or became military before the end of their design life or are in long term storage, or are engaged in low hours situations & so all have generally very low flying hours.
hindsight ,........unfortunately ,.... is usually. best
Anyone knowledgeable on this topic could see the Comet Disaster coming... de Havilland had no real experience with riveted aluminum airframe design and construction, they were among the very last manufacturers of aircraft made primarily from wood and fabric, even their jet had wood and fabric fuselages.
The real tragedy of the Comet Disaster was that it could have been easily prevented if de Haviland had simply followed well-known and understood industry standards for the design and construction of pressurized cabins made from riveted aluminum alloys
@@WilhelmKarsten
Fryed Ryce Muncherz shud note -
*_How things were back then._*
*_Accident losses - % of aircraft built._*
DeHavilland Comet 4 UK 14%
DeHavilland Comet all mks 17%
Vickers VC10 UK 5%
Douglas DC-1 99%
Douglas DC-2 47%
Douglas DC-3 30%
Douglas DC-4 26%
Boeing s300 72%
Boeing 247 48%
Boeing 707 20%
Lockheed Electra 29%
DO THE LOCKHEED L-188 ELECTRA WITH THE WINGS RIPPING OFF DUE TO WHIRLMODE, PLEASE.
Thats why all airliners today have square windows.
They all have radius corners, in hindsight we know that the shape of the windows had absolutely nothing to do with the catastrophic in-flight structural failures of the Comet.
*Krapper & co 😅😅😅👍🇮🇪*
🇨🇳 Have they had chicken chow mein for dinner today🇨🇳?
*They might like to try reading the questions & attempt a coherent reply in glorious victorious ENGLISH. THE WORLDS MOST WIDELY SPOKEN VICTORIOUS GLoRIOUS PEOPLE'S INTERNATIONAL LANGUAGE & THE MANDATORY VICTORIOUS GLoRIOUS PEOPLE'S COMMERCIAL AVIATION LANGUAGE.*
*Wrong Answer.*
They might like to memorize.
*_More than 33,000 Whittle style centrifugal compressor internal combustion gas turbine aircraft engines have been produced, from the time Whittle demonstrated his aircraft engine for the first time in the world, to the present date._*
*How many fixed wing & rotating wing aircraft types have used the Whittle Gas turbine aircraft engine including reverse flow combuster type engines?*
Also, if they would like to discuss inventions, the gas turbine was invented in the people's republic of glorious England before the 1800s. Which glorious & infinitely superior & always victorious English person invented the gas turbine engine before 1800?
*_DON'T TRY INTIMATING ME SONNY?_*
*JUST THE FAX HERE BOY*
Crack was said to start at an adf antenna.
Also said the metal was thin because the engines weren't powerful enough so had to keep aircraft light.
Oh, click bait. "It's wasn't the square windows". But it was....
It was not the square windows, this red herring myth was completely debunked when wreckage recovered from the sea confirmed that the passenger windows were not related in any way with the catastrophic in-flight structural failures.
@sandervanderkammen9230
*UPDATE MORE BREAKING NEWS ETC*
De Havilland (Of England) Comets / Nimrods were not grounded after 1970 due to structural problems.
Issues related to the Comet's windows & their shape are indeed very relevant, if someone states it was the square windows or wasn't the square windows they probably don't have the complete picture of what the problems were.
Of course it should indeed be noted that as far as flying stresses are concerned the Comet & Nimrod had particularly robust airframes.
*_It's interesting that some of the aircraft on the list should really have been noticeably safer than the Comet due to being a similar type but of much later design & manufacture but they definately were not safer._*
How things were back then -
*_Accident losses - % of aircraft built._*
DeHavilland Comet 4 UK 14%
DeHavilland Comet all mks 17%
Vickers VC10 UK 5%
*_The DH Comet had better safety than or similar safety to many other commercial passenger aircraft of a similar era_*
Douglas DC-1 99%
Douglas DC-2 47%
Douglas DC-3 30%
Douglas DC-4 26%
Boeing s300 72%
Boeing 307 70%
Boeing 247 48%
Boeing 707 20%
Lockheed L-049/149 Constellation 30%
Lockheed Electra Turboprop 29%
Fairchild FH-227 30%
McDonnell Douglas DC-8 14%
Sud Aviation Caravelle 15%
Canadair CL-44 Turboprop 46%
Convair CV-580 Turboprop 22%
A comparison of more recent aircraft.
Accident losses comparison examples.
1970s - 1980s
% of total Aircraft built
Similar aircraft type, date / decade, useage, size.
Biz Jets
BAe-125-800 1.7 %
Beechcraft Beechjet 400 2.2 %
Cessna 550 Citation II 7.1 %
Learjet 35 / 36 12 %
Beechcraft 1900 6%
Dassault Falcon 10 11.5%
Aérospatiale SN.601 22.5%
Medium size jets / Turboprops.
BAe-146 5.1%
Fokker 100 6%
McDonnell Douglas DC-9-30 9.5%
Fairchild FH-227 30%
McDonnell Douglas DC-8 14%
Canadair CL-44 Turboprop 46%
Convair CV-580 Turboprop 22%
Beechcraft, Fokker, McDonnell Douglass, Learjet, Fairchild, Aerospatiale, Canadair, Convair companies defunct.
All Comets, including some Comet 1s, had full civilian use certification at some point after 1954, civilian use certification only being withdrawn after commercial flying stopped. Examples were flying until 1997 - one example did a signals research global circumnavigation flight series in 1993 via Australia virtually without a rest travelling 28000 miles, only had an ice warning indicator issue during the flights.
*The DH Comet - World Firsts.*
1st gas turbine jet powered airliner. 1st high altitude 8psi pressurised full fuselage length passenger cabin airliner, not a trivial feature as structure strength required for pressurisation considerably exceeded strength required for normal flying stress. Nobody else had done anything similar before the Comet.
The b-47 used 2 relatively small, heavily built pressurised modules (the aircraft where 6 had their wings fold up in 2 months while flying & some had their wings fall off while parked).
The 1937 Boeing piston engined airliner pressurised passenger cabin was pressurised to 2 psi only - in fact that could easily be done as the normal unpressurized fuselage cabin structure strength for flying stresses only was all that was needed to be adequate so no significant weight increase issues needed addressing.
1st all hydraulically powered flying surface controls & actuators airliner with under carriage wheel disk brakes + ABS.
1st jet airliner to cross the Atlantic.
1st jet aircraft to do a world circumnavigation flights series.
*Of course De Havilland had prior experience building many all metal construction airframe aircraft including thousands of jet powered fighter aircraft that were primarily of metal construction with pressurised cockpits & jet engines built by De-Havilland & we know the world's first all metal construction airframe airliner was built in England in the 1920s by Handley Page.*
*_De Havilland did indeed always work to better than industry standards at the time, used up to date knowledge for the design & no evidence of negligence or criminal negligence was ever produced in relation to the DH Comet._*
The course of De Havilland & the general UK aerospace industry sector was not affected even slightly by the DH Comet.
*_Other interesting World firsts_*
_World's first turboprop aircraft._
*Vickers Viscount Turboprop Airliner 1947.*
*A 1945 Gloster Meteor Aircraft with Turboprop Gas Turbine Engine.*
People might like to have a go at these questions.
*Which airline has just ordered*
*60 RR England Trent XWB Engines*
*& What aircraft are the engines for?*
_Bonus question for 10 points._
Which country has the
*World's Highest Combined Per Capita*
*Nuclear + Defence + Aerospace Sector Activity?*
Cheers.
_Toodle_ -PIP- *Old* *_Chaps / Chapesses._*
. ......
. .... . ... . ... ..
... ..
.. ... ....
Ivcxivcx
ivcxcxii
vxvivcxiccxxcc
It was the square windows ffs.
No it wasn't, wreckage recovered from the sea confirmed that the passenger windows were not involved in the catastrophic in-flight structural failures.
The Comet had aluminum skins that were too thin and brittle, lacked proper Rip-stop doubler joints and the fuselage frame hoops and stringers were too weak to prevent cracks from joining up with adjacent panels. de Havilland used riveting methods that were not appropriate for pressurized cabins and well below industry standards.
de Havilland simply lacked the experience to build all-metal aircraft with pressurized cabins... they were still building aircraft primarily from wood and fabric
4:34 😂😂😂 Are we supposed to take this nonsense seriously?
Wtaf.
Chow Mein gobblers should be aware.
*_Accident losses - % of aircraft built._*
DeHavilland Comet 4 UK 14%
DeHavilland Comet all mks 17%
Vickers VC10 UK 5%
Boeing 707 USA *20%*
Lockheed Electra USA *29%*
What a huge pile of bovine xkreemunt!?
😅👍😅😅
An idiotic report, and an unforgivable waste of 11 minutes of my life
Indeed, the Comet Disaster was simply the result of egregious engineering incompetence and criminal negligence on behalf of de Havilland, these people has no business, and certainly no experience building jet airliners... these clowns were still building planes out of wood and fabric in the 1950s.
@@sandervanderkammen9230
Kharzeestan Krappenz DiktorBummer Jurkzxoffenz etc and co - they should all note good with much awestruckness & extreme wonderment.
*UPDATE MORE BREAKING NEWS ETC*
De Havilland (Of England) Comets were not grounded after 1970 due to structural problems.
*_It's interesting that some of the aircraft on the list should really have been noticeably safer than the Comet due to being a similar type but of much later design & manufacture but they definately were not safer._*
How things were back then -
*_Accident losses - % of aircraft built._*
DeHavilland Comet 4 UK 14%
DeHavilland Comet all mks 17%
Vickers VC10 UK 5%
*_The DH Comet had better safety than or similar safety to many other commercial passenger aircraft of a similar era_*
Douglas DC-1 99%
Douglas DC-2 47%
Douglas DC-3 30%
Douglas DC-4 26%
Boeing s300 72%
Boeing 307 70%
Boeing 247 48%
Boeing 707 20%
Lockheed L-049/149 Constellation 30%
Lockheed Electra Turboprop 29%
Fairchild FH-227 30%
McDonnell Douglas DC-8 14%
Sud Aviation Caravelle 15%
Canadair CL-44 Turboprop 46%
Convair CV-580 Turboprop 22%
A comparison of more recent aircraft.
Accident losses comparison examples.
1970s - 1980s
% of total Aircraft built
Similar aircraft type, date / decade, useage, size.
Biz Jets
BAe-125-800 1.7 %
Beechcraft Beechjet 400 2.2 %
Cessna 550 Citation II 7.1 %
Learjet 35 / 36 12 %
Beechcraft 1900 6%
Dassault Falcon 10 11.5%
Aérospatiale SN.601 22.5%
Medium size jets / Turboprops.
BAe-146 5.1%
Fokker 100 6%
McDonnell Douglas DC-9-30 9.5%
Fairchild FH-227 30%
McDonnell Douglas DC-8 14%
Canadair CL-44 Turboprop 46%
Convair CV-580 Turboprop 22%
Beechcraft, Fokker, McDonnell Douglass, Learjet, Fairchild, Aerospatiale, Canadair, Convair companies defunct.
All Comets, including some Comet 1s, had full civilian use certification at some point after 1954, civilian use certification only being withdrawn after commercial flying stopped. Examples were flying until 1997 - one example did a signals research global circumnavigation flight series in 1993 via Australia virtually without a rest travelling 28000 miles, only had an ice warning indicator issue during the flights.
*The DH Comet - World Firsts.*
1st gas turbine jet powered airliner. 1st high altitude 8psi pressurised full fuselage length passenger cabin airliner, not a trivial feature as structure strength required for pressurisation considerably exceeded strength required for normal flying stress. Nobody else had done anything similar before the Comet.
The b-47 used 2 relatively small, heavily built pressurised modules (the aircraft where 6 had their wings fold up in 2 months while flying & some had their wings fall off while parked).
The 1937 Boeing piston engined airliner pressurised passenger cabin was pressurised to 2 psi only - in fact that could easily be done as the normal unpressurized fuselage cabin structure strength for flying stresses only was all that was needed to be adequate so no significant weight increase issues needed addressing.
1st all hydraulically powered flying surface controls & actuators airliner with under carriage wheel disk brakes + ABS.
1st jet airliner to cross the Atlantic.
1st jet aircraft to do a world circumnavigation flights series.
*Of course De Havilland had prior experience building many all metal construction airframe aircraft including thousands of jet powered fighter aircraft that were primarily of metal construction with pressurised cockpits & jet engines built by De-Havilland & we know the world's first all metal construction airframe airliner was built in England in the 1920s by Handley Page.*
*_De Havilland did indeed always work to better than industry standards at the time, used up to date knowledge for the design & no evidence of negligence or criminal negligence was ever produced in relation to the DH Comet._*
The course of De Havilland & the general UK aerospace industry sector was not affected even slightly by the DH Comet.
*_Other interesting World firsts_*
_World's first turboprop aircraft._
*Vickers Viscount Turboprop Airliner 1947.*
*A 1945 Gloster Meteor Aircraft with Turboprop Gas Turbine Engine.*
They might like to answer these questions.
*Which airline has just ordered*
*60 RR England Trent XWB Engines*
*& What aircraft are the engines for?*
_Bonus question for 10 points._
Which country has the
*World's Highest Combined Per Capita*
*Nuclear + Defence + Aerospace Sector Activity?*
👍 & 🙂 & of course 😎 indeed.
*C H E E R S* & without doubt -
_Toodle_ -PIP- *Old* *_Chap._*
. .... . ... . ... . ...
... .... ... ... ....
Ivcxivcxivcxcxiivx
vivcxiccxxcccxcv
American ignorance is everlasting
British incompetence brought down its entire aircraft industry....
@@WilhelmKarsten
Muncherz Krappenz DiktorBummer KARZEESTAN Jurkzxoffenzstadt & co - they should all note with much awestruckness and great wonderment.
*****
*How come they can't answer simple questions - why is that?*
*****
*_DID SOMEBODY ACTUALLY SAY SOMEWHERE THAT THERE'S AIRLINER ASSEMBLY LINES OR SIMILAR IN THE UK OR IRELAND OR THAT Airbus or BOW-WING is actually British? (B-47 wings on many occasions folded up in flight or dropped off while parked)._*
Of course Brazil makes very good airliners & Brazil is 100th down list along with Indonesia for wealth per capita.
*Norway Holland Denmark Ireland Belgium - Top 20 wealth per capita - Don't make airliners - its as simple as that.*
BAe Systems & RR combined now do more Airbus work than Germany on an absolute basis & significantly more work than that on a per capita basis.
Per capita for the home nation BAe Systems is the world's largest defence contractor.
_BAe systems announced the recent £4 Billion takeover of Colorado based US based Ball Aerospace._
*BAE systems now does a significantly higher value of work for Airbus than it did when it was a major Airbus shareholder before 2005.*
*_RR now owns US Engine maker Allison for example which does classified Aerospace work for the US Govt._*
The UK has more important stuff to do these days.
_Routine simple passenger aircraft airframe assembly is becoming more of a 3rd world / trailer park area thing._
EG -
*_The DH Comet - world's first high altitude capable pressurised passenger cabin jet airliner in regular service, world's first jet airliner aircraft to cross the Atlantic, worlds first jet airliner aircraft to complete a global circumnavigation flight series._*
*They might try to sensibly answer this question - why do they believe that BAE Systems & RR (aero engines etc) & other companies, for example should be doing anything other than what they currently do & where do they get the idea from that the DH Comet had any affect at all on the progression UK aerospace sector.*
*Anybody currently flying on a widebody airliner stands a good chance of being on an aircraft powered by RR gas turbine aero engines built in England.*
📯📯📯📯
*The New RR Trent Ultrafan*
*Built In England*
*_World's Largest (see T&Cs)_*
*_Gas Turbine Aero Engine_*
📯📯📯📯
👍Manufactured by the people on a small island with less than 1% of the world's population.👍
*_A typical but small glimpse of what goes on in the very internationally orientated British aerospace sector._* -
Boeing Apache Attack Helicopter.
AH-64: *75 UK suppliers,* 7% UK content, global fleet of 1280+ aircraft.
*F35B more than 130 UK Suppliers, more than 30% UK content.*
*_F35A & F35C more than 130 UK Suppliers, more than 15% UK content._*
They might like to answer these questions.
*Which airline has just ordered*
*60 RR England Trent XWB Engines*
*& What aircraft are the engines for?*
_Bonus question for 10 extra points._
Which country has the
*World's Highest Combined Per Capita*
*Nuclear / Defence / Aerospace Sector Activity?*
👍 & 🙂 & of course 😎 indeed.
Cheers.
_Toodle_ -PIP- *Old* *_Chap._*
. ... . . ..... . . ... . . ... . ...... . . .. . .
ccicci vivvixxvvvvvvvvvixxiccicci
Etc
Can we not have a thumbs down button added on youtube for the clickbait untruths in titles please youtube.....You WONT be getting my subscription for misleading titles
*IT WASN'T THE SQUARE WINDOWS.*
Don't stress it, I gave him a sub after reading your whiny post because I know how much the knowledge of that will really grind your gears.
@@sandervanderkammen9230
@sandervanderkammen9230
Kharzeestan Krappenz DiktorBummer Jurkzxoffenz etc and co - they should all note good with much awestruckness & extreme wonderment.
*UPDATE MORE BREAKING NEWS ETC*
De Havilland (Of England) Comets were not grounded after 1970 due to structural problems.
*_It's interesting that some of the aircraft on the list should really have been noticeably safer than the Comet due to being a similar type but of much later design & manufacture but they definately were not safer._*
How things were back then -
*_Accident losses - % of aircraft built._*
DeHavilland Comet 4 UK 14%
DeHavilland Comet all mks 17%
Vickers VC10 UK 5%
*_The DH Comet had better safety than or similar safety to many other commercial passenger aircraft of a similar era_*
Douglas DC-1 99%
Douglas DC-2 47%
Douglas DC-3 30%
Douglas DC-4 26%
Boeing s300 72%
Boeing 307 70%
Boeing 247 48%
Boeing 707 20%
Lockheed L-049/149 Constellation 30%
Lockheed Electra Turboprop 29%
Fairchild FH-227 30%
McDonnell Douglas DC-8 14%
Sud Aviation Caravelle 15%
Canadair CL-44 Turboprop 46%
Convair CV-580 Turboprop 22%
A comparison of more recent aircraft.
Accident losses comparison examples.
1970s - 1980s
% of total Aircraft built
Similar aircraft type, date / decade, useage, size.
Biz Jets
BAe-125-800 1.7 %
Beechcraft Beechjet 400 2.2 %
Cessna 550 Citation II 7.1 %
Learjet 35 / 36 12 %
Beechcraft 1900 6%
Dassault Falcon 10 11.5%
Aérospatiale SN.601 22.5%
Medium size jets / Turboprops.
BAe-146 5.1%
Fokker 100 6%
McDonnell Douglas DC-9-30 9.5%
Fairchild FH-227 30%
McDonnell Douglas DC-8 14%
Canadair CL-44 Turboprop 46%
Convair CV-580 Turboprop 22%
Beechcraft, Fokker, McDonnell Douglass, Learjet, Fairchild, Aerospatiale, Canadair, Convair companies defunct.
All Comets, including some Comet 1s, had full civilian use certification at some point after 1954, civilian use certification only being withdrawn after commercial flying stopped. Examples were flying until 1997 - one example did a signals research global circumnavigation flight series in 1993 via Australia virtually without a rest travelling 28000 miles, only had an ice warning indicator issue during the flights.
*The DH Comet - World Firsts.*
1st gas turbine jet powered airliner. 1st high altitude 8psi pressurised full fuselage length passenger cabin airliner, not a trivial feature as structure strength required for pressurisation considerably exceeded strength required for normal flying stress. Nobody else had done anything similar before the Comet.
The b-47 used 2 relatively small, heavily built pressurised modules (the aircraft where 6 had their wings fold up in 2 months while flying & some had their wings fall off while parked).
The 1937 Boeing piston engined airliner pressurised passenger cabin was pressurised to 2 psi only - in fact that could easily be done as the normal unpressurized fuselage cabin structure strength for flying stresses only was all that was needed to be adequate so no significant weight increase issues needed addressing.
1st all hydraulically powered flying surface controls & actuators airliner with under carriage wheel disk brakes + ABS.
1st jet airliner to cross the Atlantic.
1st jet aircraft to do a world circumnavigation flights series.
*Of course De Havilland had prior experience building many all metal construction airframe aircraft including thousands of jet powered fighter aircraft that were primarily of metal construction with pressurised cockpits & jet engines built by De-Havilland & we know the world's first all metal construction airframe airliner was built in England in the 1920s by Handley Page.*
*_De Havilland did indeed always work to better than industry standards at the time, used up to date knowledge for the design & no evidence of negligence or criminal negligence was ever produced in relation to the DH Comet._*
The course of De Havilland & the general UK aerospace industry sector was not affected even slightly by the DH Comet.
*_Other interesting World firsts_*
_World's first turboprop aircraft._
*Vickers Viscount Turboprop Airliner 1947.*
*A 1945 Gloster Meteor Aircraft with Turboprop Gas Turbine Engine.*
They might like to answer these questions.
*Which airline has just ordered*
*60 RR England Trent XWB Engines*
*& What aircraft are the engines for?*
_Bonus question for 10 points._
Which country has the
*World's Highest Combined Per Capita*
*Nuclear + Defence + Aerospace Sector Activity?*
👍 & 🙂 & of course 😎 indeed.
*C H E E R S* & without doubt -
_Toodle_ -PIP- *Old* *_Chap._*
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