Why Did Her Stern Vibrate So Much?
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- čas přidán 23. 06. 2022
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------------------ABOUT THIS VIDEO------------------
In this video, we investigate the story of the RMS Lusitania.
Timecodes:
Intro - 00:05
Background about liners - 00:37
Sponsor Segment - 01:06
JP Morgan - 02:20
Significance of Cunard - 02:54
What does RMS mean? - 03:23
Lusitania Launching - 01:53
What Caused The Vibrations? - 04:46
Solving the problem - 06:23
Lusitania Maiden Voyage - 06:42
Lusitania Sinking - 07:44
Lusitania Location - 09:04
Causes of the sinking - 09:24
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@@RmsTitanic59 Why?? Let him make money, he puts effort into making FREE enjoyable content for us. Why shouldn't he be rewarded?
You should make a video about the italian ship that couldnt float. I cant remember its name but if you google it, your bound to find it. It happened in 1900-1910 i think)
Video on how to stop ship vibrations soon pls
why did your animations show the ships being launched at such a steep angle?
@@Unbreakify Princepessa Jolanda
"Where are you headed?"
"A weapons testing facility."
"Really? What are you carrying?"
"Oh... Uh... Cheese."
"Understandable, have a great day"
as a ship i can relate*
@@SparePlayss understandable, eat a torp
Weapons testers need provisions.
Testers have standards.
In our nuclear plant we have certain resonances down towards the lower end of rotation speeds on the steam turbine. Keep in mind these turbines are massive with 1 high pressure impeller and 3 low pressure impellers all attached on the same shaft.
Especially during shutdown the turbines cross their resonance speeds and shake the whole turbine building despite it being a massive concrete and steel structure.
My ship (USS Enterprise CVN65) had a bent shaft, caused quite a bit of vibration at higher speeds (which we frequently ran at higher speeds). I don't recall our turbines having any particular vibration, though our pumps and everything contribute to overall vibration when inside the plant. Us reactor plant guys slept in the aft of the ship on the 2nd deck and so we got to enjoy the sweet vibration of #4 shaft (which I was told was bent on a grounding in San Fransisco).
@@jimmym3352 Wow this is really interesting, I know the chance is slim, but do you have any further information about this? What specifically bent the shaft? What was the deviation and rotation speed? I'd love to do some calculations and see the forces applied on each rotation.
@@SECONDQUEST I don't have much information except what I was told (which I can't verify the accuracy of). I was told it ran aground in San Fransisco Bay in the 80's. This was before I was stationed there, back when it was stationed on the West Coast. I was there when it was stationed out of Norfolk. I wouldn't know any of the speeds involved, at the time of the grounding I'm sure it was extremely slow. Now at top speeds, it is rated at 70,000 shaft horsepower. 280,000 for all 4 shafts.
Now normally, cavitation is a thing on high speed operation of the screws (or propellers) anyways, but ours was especially bad because of that issue.
@@jimmym3352 Isn't the info he asked for classified? Since one could use them to figure out or verify the real capabilities of the ship.
@@M_Northstar It might be, regardless, only the designers/engineers would know those things. The ship was designed in the 50's, it's not exactly state of the art. And the ship has been decommissioned for 10 years now. Certainly not the last to carry that name...
I’d love to see a video on survival suits and how they work, what features they have, how much they cost, etc.
👆 Looks like we have a new topic for a future video
Also what happens to the passengers when a ship sinks - what causes part of the passengers to survive while the other group perishes, mistakes that passengers make in such scenarios, what can be done to avoid freezing in cold water, how hard is it to stick around the ship and avoid being dragged away by currents and waves, etc. That would be an amazing and terrifying video!
Great idea 🙂
Not exactly that topic but you can check "Why don't ships have enough lifeboats" In there he also redirects you to another channel's video that goes more in detail about what's in lifeboats and so om
@@sam08g16 yes yes yes! This is what I want to see next!
Having beein looking into the case of the "RMS Lusitania" several times over the last 20 years, a detail struck me:
Why did the captain of U-20 shoot only one torpedo at such a prime target when he still had four loaded? Can't get a much more prestigious or high-tonnage civilian target than "RMS Lusitania," right?
My most logical conclusion was that he wanted to cripple, not sink the ship. Torpedos of the time were much less effective due to magnetic detonators still not invented for torps. This led to ships half the size of Lusitania sometimes taking two or three torpedos and still not sink. He knew exactly which ship he had in his crosshairs. He knew there were a thousand or more civilians on board. Shooting one torpedo was likely just to damage the ship or let it sink very slowly, giving the people on board a good chance.
He was under orders to shoot up everything he came across. If he hadn't shot, he would have been court martialed.
So damaging Lusitania badly would serve the war by leaving it in port for repairs for months, still give the civilians a chance and not force him to commit treason to duty.
The extremely quick sinking with that loss of life might be one of the most unlucky moments in naval history (if my conclusion is right).
I like this logic, good breakdown
@@aaronoconnor9780 Thank you. :)
V interesting take, nice one
The U-boat Captain stated his reasoning was one fish to the steamer to lay her up and keep the other two in case he came under attack on the way back to base. He and his staff were also very surprised Lusitania sank so rapidly, but thought the secondary explosions were what sank her.
Remember that the Germans were quite aware that she had her lower holds full of US munitions bound for England. When you know that you are basically torpedoing a munitions ship, it doesn't take a full spread at close range.
Although it has been contested ever since that she was carrying munitions and thus a valid military target, more recent discoveries of the Bills of Lading from the US side and the fact that the British government has finally come out and said to not dive on the wreckage due to large amounts of unexploded ordnance on the wreck site have pretty much put that particular fiction to rest.
Big props (pun definitely intended) for including that quirky anecdote! It made the video that bit sweeter.
I really enjoyed the little anecdote about the modern cruise ship - it is interesting to see that even decades later we are still running into similar issues.
I’m keen to understand how they pulled off that propeller swap where that’s the easy part: I don’t understand how you just put the motor and reduction gear rotating in the other direction ….that sounds difficult or at least certainly without complications.
You can't really full resolve vibrations from resonance frequency. This happens on all structures, from ships, bridges, to buildings. And all of these had have problems in the past. You can try changing the dimensions of a ship to change its frequency so it doesn't match that of the ship's operation. But this can only be done during the design phase. Otherwise you have to avoid operating at that frequency. Strengthening the structure, dampeners/shock absorbers, and limiting the whatever is contributing to the vibration helps but never fully resolves it. This is even harder to do with bridges and buildings since most of the effects come from winds... and you can't control that. Best engineers can do is estimate the average weather and design around that.
@@JoeOvercoat electric motor only needs a phase wire swapped. 2stroke diesel can run backwards. Even a 4 stroke would only need new valve train. Gearbox you could swap left to right.
Talking out my arse. I have no idea how boats work.
@@mabamabam At the sizes and efficiencies that we’re talking about I would expect that the crankarms and the transfer cases prefer a direction given my crude understanding because also talking out my arse…but thinking this can’t be simple and something this big putting out this much power.
@@JoeOvercoat I though 2 strokes were designed to run in reverse. But you're probably right on the crank of a 4 strokes.
But don't cruise ships generally just run electric drive. They have such high hotel loads and comparatively low sailing time that they just have a bunch of high speed diesels turning generators. That way they can juggle electric loads more efficiently
There was an interesting incident that happened to Lusitania in 1910. She was sailing through a storm when a rogue wave higher than her bow slammed right into her. equipment was torn off the forecastle and the top of the wave rolled over the bow and smashed into the bridge, shattering all the windows and warping the whole structure of the bridge. Fortunately, nobody was hurt and Lusitania was repaired.
😯 this ship was way better than Titanic
@@unabhangigenachrichtensh7296 In what regard?
@@mgmg116 always
@@unabhangigenachrichtensh7296 Got any specifics or just a claim?
@@mgmg116 so I am there, as far as I know, the Lusitania did it.
"It is true that some weapons were aboard, Ms. Preston said. The ship's manifest made no secret that it carried weapons in its hold, including 4,200 cases of Remington rifle cartridges and 1,250 cases of shrapnel shells and fuses". What pops up when you google whether the Lusitania carried weapons. If the ship was German, we wouldn't have heard the end of how it was carrying weapons thus being a legitimate target.
And it would be just as much infuriating, killing more than a thousand innocent people who didn't know they were being used as meatshield...
@@daftbence why tf were civilians even traveling the Atlantic during a war absolute morons....people run away from wars these guys were going towards it...
@@daftbence The fault lies with the people who made the decision to use human shields. I thought that was pretty clear when ISIS used prisoners in the same way to protect its convoys from drones. Same tactics.
@@cerealkiller7143 That was my point. No matter who else would have done this, it is a horrible thing and shame on them. But history is written by the victors so sadly if the ship was German, as you said it, everyone would try to wash their hands because "it was carrying weapons"...
@@daftbence Yes and if you read or just look into the book Dead Wake it gets even more tragic
There is no mystery about RMS Lusitania, it did carry ammunition and the information was available for quite some time. In 1982, the head of the Foreign Office's American department finally admitted that there is a large amount of ammunition in the wreck, some of which is highly dangerous and poses a safety risk to salvage teams.
Which also means that she was a legitimate target under the laws of war and her torpedoing was NOT a war crime.
None of it however exploded. It was mostly small arms ammunition.
@@joergmaass Maybe not her specifically but the Germans torpedoed the crap out of merchant ships throughout WW1, so it doesn't make much of a difference.
@@bobbygetsbanned6049 Yes, it does. Torpedoing a ship flying a hostile flag or transporting military goods is not a war crime, but a legitimate act of war. The Union during the Civil War actually established that principle when they attacked and seized (neutral) British ships under the provision that they transported military goods or Confederate personnel. Learn your history and the facts!
@@joergmaass In the end, sinking this ship was the short sighted move the German navy could have made. It effectively sealed their fate.
Aircraft with multiple propellors have equipment to sync them so the beats on the fuselage are _out_ of sync. This equipment is deliberately turned off for takeoff so one engine failure doesn't drag down the others.
Whoa, cool
This is the first I’ve heard of the engines being synced with anything other than the cowl mounted weapons.
oh that's a cool bit of info you share!
Synchrophasing, not only same rpm but which blade is in a desired position compared to neighbours.
Absolutely incorrect regarding the engine failure part of the auto synch feature on propellers. Usually only the larger planes have auto sync. The pilot can achieve it very easy on smaller planes at any point during operation by reducing the propeller rpm on just one engine by as little as 25rpm to achieve perfect prop sync.
The ship was confirmed for carrying munitions by divers. The second explosion however wasn’t because of those munitions as it was all still intact. I believe it was a boiler explosion
A coal dust explosion is more likely
The German sub commander said there was an enormous second explosion and added "boiler or coal(dust) or powder (gunpowder/munitions)".
Coal dust explosion. One of the bunkers deflagrated.
If it was coal dust it would’ve happened when the torpedo hit due to where her coal bunkers where located. The second explosion happened shortly afterwards I think it’s a boiler explosion because the cold water had to reach the hot boilers and that doesn’t happen immediately like a coal dust explosion would have. It wasn’t ammunition because they found it intact when they sent divers down. I’m a licensed engineer and it’s my professional opinion
@@aceofspades1849 we don't know how many seconds had passed between explosions. Only that it was very soon after. And that it was way stronger than the torpedo hit
I have a relative on my Mother's side who survived the sinking, her name is Thirza Winter and I have newspaper cuttings from the time when she was interviewed for the local paper. She went down with the ship, her clothes torn off with the explosions yet managed to reach the surface and find a life raft, she's noted as having saved many of those aboard the life raft.
The Kaiserliche Kriegsmarine did switch to indiscriminate submarine warfare bc the British were breaking navalwarfare agreements bc when a german submarine was searching a civilian vessel as it was allowd, for wargoods to determine if it was as a wargoodstransport a legitimate target of war, british vessels just started Ramming submarines before a search could be conducted also ships were fitted with auxiliary armaments, which made them warships as auxiliary cruisers, and thus legitimate targets, and then demounted them sometimes again, so it was impossible to know what a civilian vessel was and what a wargoods transport, this forced the K. Kriegsmarine to attack suspicious ships without search. as the regular acts of war by british civilian ships actualy meant they all acted was warships and thus were legitimate and legal targets.
aslo warnings were issued in the USA wo warn American civilians to not use the british wargoodtransports, that disguised themselfs as civilians vessels, which was an illegal action under the running agreements about naval warfare.
Indeed, British Q ships are really what triggered German unrestricted submarine warfare, and Britain honestly had it coming. The US were pretty neutral and in many ways naive to think that they can just waltz into a gigantic European/global war zone and expect no collateral damage. But then again, every participating power was pretty naive entering the war. US at this point also was willing to supply military aide making them legitimate targets despite otherwise being neutral.
Shhh... we dont talk about the war crimes the british did to get the US to join them.
@@neurofiedyamato8763 tht military aide shit while staying neutral is A class baiting technique again and again, to make it seem to the public as if they were attacked
As it was allowed?
@@annoyingbstard9407 The rules of warfare at the time allowed a vessel belonging to one of the combatants to stop and board an allegedly neutral vessel in order to determine if they were carrying munitions or military supplies. If they were not carrying such materials , the Germans were known to politely send them on their way, frequently with a token gift for the inconvenience. If the vessel WAS carrying war materials, the Germans would force the crew into the lifeboats and sink the ship. There are several recorded instances of the Germans transmitting "in the clear" the coordinates of the sinking so that the crews could be rescued.
Other common areas for vibration are misalignment of the engine, thrust block and stern seal. As for the propeller you will generally find that most hull shapes shadow the props entirely and thus the beating against the hull rarely occurs. Warships have their props in clear water for obvious reasons, but its a real bummer if they run aground and they do from time to time. Also the shaft brackets can cause problems if the angle between the A bracket legs is too close to the angles between the blades, resonance will occur.
Are we really gonna ignore the thumbnail “make her vibrate”
What about harmonic rythm.
@@quartusbuys6831 that is a common one as well. The North Carolina class of battleships, North Carolina and Washington, had the same issue at the top end of their speed regime. Through some redesign of the stern they were able to shift the vibration to a lower regime, so they could steam at full speed and be able to aim their guns.
@@hokutoulrik7345 Interesting. Thankyou for that bit of info.
@@quartusbuys6831 no problem. The North Carolinas gave the Navy fits back when they were launched because they had planned to use the same setup on the Iowas and Montanas.
This is from wikipedia "after the war it was revealed that at the time of her sinking she was carrying over 4 million rounds of machine-gun ammunition (.303 calibre), almost 5,000 shrapnel shell casings (for a total of some 50 tons), and 3,240 brass percussion artillery fuses"
In my eyes it was a 'legitimate target' at the time, though we shouldn't forget that the Uboat crew never checked their cargo (which at some points in the war was common practice) but instead sunk them without warning.
Basically if the British hadn't hidden munitions in the Lusitania, it's likely that the Uboat would have done the exact same thing. In which case there would be no denying that the sinking would have been completely illegitimate.
You should also note that most of the times the germans tried to check british ships's cargo they were instead rammed or shot at so eventually the german government declared that it would sink ANY sispicious british ship without warning and warned american passengers to not use british ships because of this (don't remember if it was before of after Lusitania's sinking though) . Not trying to side with the germans here but if this happened after that decree british claims of an unfair sinking were most likely propaganda to get political support from the americans to join the war and increasing their soldier's motivation to kill them
I think we're venturing into the realm of the "two wrongs". It's wrong to sink a ship of innocent people who mean you no harm, AND it was wrong to use those people as a "human shield"... but, sometimes, people really want a war, where we can argue "necessary" instead of "right".
Questions about the morality of various convoy and u-boat/submarine tactics are similar in my eyes to questions about the morality of strategic wide-area bombing campaigns.
Both sides were doing it, and whether it was called "strategic area bombing of valid military targets" or "indiscriminate terror bombing of innocent civilians" simply depends on which side you're talking about and from what point-of-view.
War makes savages of us all, basically.
I dunno, going right into a war zone seems pretty dumb to me. The British were also completely blockading Germany at the time, so turnabout is fair play.
i read some years ago that the germans were tipped off and knew about the munitions but i'm not sure if this is true
US aircraft carriers shake like crazy as well at higher knots my first deployment i was in the head far aft when we started gaining speed it almost shook me of the shitter lmao i didnt know what was happening it just became the norm i knew it only happened at higher speeds but now i know what causes it Thanks!
Seems fairly common with high speed ships in general and is unavoidable because resonance frequency is just physics, you can't eliminate it. You can design so the natural frequency will never align with any vibrations created by your equipment. But easier said than done as usually length and rigidity determines that. But obviously there's a lot that goes into ship length and rigidity like speed, hydrodynamics, sound, structural integrity etc. Another way would be strengthening structures or dampeners to absorb the shock. Another way would just finding ways of limiting the initial vibration, such as in the video, swapping the propeller rotation, or indeed just not operate at certain RPM. Engines and propellers aren't the only thing that can cause such vibration but is one of the common reasons it happens on ships. Buildings and bridges can also suffer from resonance frequency, as do any thing really, including wine glasses...
@@neurofiedyamato8763 There are tuned mass dampers and simply adding weight shifts the frequency too.
Billion dollar health and safety contract idea-
Shaft vibrations? Rough seas? list? Just wanting to feel like a pilot for your morning dump?
Never get tossed into a dispenser ever again with *SHITTER HARNESS.*
[pitch plays of some dude LARPing Top Gun with a five point on a basic commode, lmao]
_hans device sold separately_
Divers found munitions on the wreck of the Lusitania quite a while back, so it isn't really a mystery of whether or not it was carrying munitions.
The British government tried their hardest to stop this, through law as well as dropping nets over the wreck to make it too dangerous for most divers or submersibles to get to, until recently.
The fact that over 1000 people were effectively used as human shields is disgusting.
Because the sinking of the Lusitania caused the US to enter the war there have been a number of conspiracy theories that the ship was set up to be sunk as the destroyer escort stayed further out to sea (allegedly), take from that what you will.
Damn, that's fucked up
It is pretty bad, but I wouldn't call this human shield. Human shields are when you use civilians as hostages to protect an obvious known military target. Human shield is a form of deterrence essentially. In this case they tried hiding the fact it was a military target to begin with. So this is more covert in nature and was never intended to be a target in the first place. The munitions is likely with US knowledge though since it was loaded up there. Honestly, Q-ships were far worse IMO because it is what led to Germany's unrestricted submarine warfare to begin with.
I doubt the US purposely set that up to enter the war. Generally speaking ASW operations is harder close to shore because it is harder to listen in on sounds when there's a lot of reflections. There was no ASDIC/SONAR yet but there were still hydrophones. This is also well before the convoy systems and ships were just sent out patrolling in fixed routes. Response to attacks were slow since communication systems at the time were still limited in range, mostly relying on more powerful shore based methods. ASW aircraft were also limited at this time. All in all, it would be irrelevant, the ocean is too big and destroyer patrols would respond too slowly regardless of where they were. Merchant escorts was not really a thing yet.
And of course, given how it took 2 years, and no major push by the government to join at this time seem to indicate otherwise. It was a PR nightmare for Germany but this isn't the first nor last time ships with US passengers onboard sank. It was one with highest publicity but there is no reason to think this specific instance is orchestrated while the dozen others were not.
Lastly, Germany had no way of knowing there were munitions on board. Nor would they know there wasn't. Rules of war prior to that point required boarding to check, and evacuating those onboard before sinking. This was no longer abided by as part of the unrestricted submarine warfare but this was not officially declared yet in 1915. And quite frankly, Germany still largely did its due diligence most of the time. The odds were that Lusitania would have been intercepted and searched rendering such a conspiratorial plan impossible in the eyes of the US.
@@neurofiedyamato8763 I'd say that since this is disputed on both sides that there are two stories to tell.
However putting more than 1000 civilian passengers on a munitions transport ship is pretty much the definition of using a human shield. It might not be a blatantly obvious human shield but both armies had their spies and no doubt the German admiralty knew that munitions were being transported on civilian ships.
Add to that the fact that civilian ocean liners were fairly heavily armed and no match for a WWI U-boat if it surfaced and used it's deck gun, torpedoing the ship would have been the only way to sink her without having a high chance of the U-boat being sunk as well.
Add to that the fact that the site of the wreck was covered by law and anti-diver and submersible weapons (nets and hedgehog mines) it seems like England didn't want the PR nightmare of "We're shipping civilians and munitions on the same ship" to come out.
Nobody wants to be sitting on tons of high explosives at sea during wartime.
✡️✡️✡️✡️👀
@@daviddavidson2357 It was munitions on a civilian transport ship, at least have it the right way around.
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Harmonics are fascinating. The Avro Lincoln Prototype that I saw still had three-bladed props for its Merlins. There were several other prototypes and all sorts of strange things happened on them (bomb doors falling open etc.) until it was suggested that the engine harmonics were not in cinc with the a/c. Four-bladed props cured the problem instantly.
I was wondering when I watched this. What if they had used 5 bladed props for outer screws and 4 bladed props for inner screws, or vice versa?
'seccond, much larger explosion from within' ... poor scapegoated souls
Boy, those ships had some strong keels. Most ships would have broken their backs being launched like that (3:56).
My grandparents lived on the old head, my great aunt claims to have seen the ship sailing that day only to have it disappear minutes later. She didnt think much of it until the news came that it was sunk
Well it was really hard to find a proper name for my new speedboat,....thanks to you I now know how to call it: M/Y Sybian, the fastest pleasure craft ever built... :-D
My dad was on the USS Ranger about 1960 and said that one of the screws made contact with a whale. The contact severely damaged the screw, one of the blades losing a significant chunk. The ship went into drydock and had the screw replaced. But he said ever since that incident it vibrated horrifically, especially in turns. He suspected the contact with the whale may have thrown the shaft out of alignment, if ever so slightly.
"What really happened to the Lusitania?"
"I don't know"
I was waiting for the rest of the video
I'm pretty thankful i checked the timestamps. Compared to this channels other content this one seemed forced to get past that 10 minute mark. Definitely a blemish on an otherwise spotless channel in my humble opinion.
The "milk" and "butter" exploded.
The John Brown Shipyard which built the Lusitania learned a lot of valuable and expensive lessons as a result of building the ship. The shipyard incurred all of the costs it took to strengthen the ship's frames after the vibration was first discovered. They took it upon themselves to apply these lessons when it came time for them the build the third Cunard Express Liner, Aquitania. Although it was never part of this ship's original design, they secretly added strengthening brackets and addition angles to the new ship's framing and decks while she was under construction. These additions added a rugged durability into the ship's overall structure that came into play much later in her life. Aquitania was still in service when WW2 broke out in Europe in September, 1939, and although she was over 25 years old at the time, the additions put into her hull by her builders at the time of construction, allowed the ship to render the difficult and demanding service that only wartime situations can create. Sailing, often alone, on lengthy voyages that took her to the far corners of the globe. She was noted by the US Army's Transportation Division as one of the most reliable troopships the Allies had in service. The ship was able to make US troop lifts of 8375 men per crossing of the Atlantic, even as she passed her 30th year. The foresight shown by her builders to try to rid the ship of possible vibration at the beginning of her life, inadvertently came into play, right when she needed it most, and it saw her safely serve through the deadliest war in history.
Aquitania sailed until the end of 1949. So John Brown & Company clearly knew how to build very strong ships.
Although it was brief, I enjoyed the anecdotal example of your time spent working on a ship with similar constraints. Would love to hear more in the future 👍
I served on a Knox Class ASW Frigate in the early 1980s. At speed, as we came down a big wave, the bow would shake, side to side. We figured the big rubber sonar dome caused it.
That's exactly what caused it. All ships equipped with the AN/SQS-26 (and later 53) sonar systems do it. I served as a Sonar Tech on USS Thomas C. Hart (FF-1092), USS Ticonderoga (CG-47) and USS San Jacinto (CG-56). The yaw effect was definitely more pronounced on the Hart but still very noticeable on the two cruisers.
Love it!! Keep up the amazing work!!!
I love the story of the Lusitania! Thank you so much for sharing it, I loved the video!
i remember reading an article a few years back were the British government admitted that the Lusitania was carrying munitions and war time supplies
Our ports were easily surveilled by the Germans. Waterfront workers knew what was loaded and where on the ship it was loaded. Of course, the German government had that information.
“Dead Wake” by Erik Larson (2016) is an interesting book about the final voyage of the Lusitania.
Was bout to comment about this good book.
"Dead Awake" is a book about a mortician's daughter who tries to solve the mystery of her ex-friend's (?) murder when the girl's dead body starts talking to her. It has no relation to navigation whatsoever.
@@sam08g16 “Dead Wake” and “Dead Awake” are two completely different books.
@@gerardacronin334 Yeap, so...?
@@sam08g16 So, why did you need to mention a book that has no relevance to the subject matter?
This was a great video. I worked on cruise ships (specifically the Queen Mary 2 that was mentioned) for years and the vibrations at high speeds were nauseating. There was one treck in the North Atlantic in the winter that had us all bedridden. For reasons, we only had 4 days to get from New York to Southampton. At nearly max speed, we were hitting 20 foot swells at one point and the ship's internal vibrations were terrible.
Oh 😯
QM2 is an ocean liner, not a cruise ship. Otherwise though, I get you. Must've been awesome. :D
@@Kaidhicksii Believe me that I'm not exaggerating when I say that I heard that line more than 1,000 times over my contracts haha
Such a neat little detail here at 6:49 that the 4 funnels begin to smoke separately as her boilers come to life.
I'll probably never get on a boat again especially out in the ocean but the way you present this information is phenomenal, can't help but watch .
Nice to see my home mentioned! For anyone interested, there's a small museum on the Old Head of Kinsale dedicated to the Lusitania. They have several artifacts from the ship, as well as one of the lifeboat davits. In fact the the museum took ownership of the wreck in the last few years.
For the conspiracy people out there, the lusitania herself was depth charged numerous times in, I think, the 60s, by the royal navy, which has almost completely collapsed her hull.
Queenstown, as mentioned in the video, is now known as Cobh ( Pronounced "Cove") and is more famous for having been the final port of call for the Titanic, prior to her setting off across the Atlantic.
Are they lying about the illegal munitions?
@@tesmith47 I don't know if they've ever admitted to it officially. However I believe that it's now considered true that she was in fact carrying munitions.
@@tesmith47 yes of course governments lied about it - it's war
Vibration issues became worse with large, slow speed diesel engines on ships. After a couple of year of shipping I developed health issues from the vibrations that went away slowly after I came ashore.
If I may ask what kind of issues can the vibration cause?
@@justinmckee2256 to avoid over sharing, let’s just say it was a waste water system issue typically found in older men.
@@stephenbritton9297 More likely a potable water storage and treatment issue. Common on civilian ships. If Officers, Engineering and Medical folks are bringing bottled water or pop onboard by the caseload, they probably know something that you don't.
We just returned from a cruise on a popular cruise line. I noticed the vibration quite a bit during our trip. A bout 2 years ago we where on a sister ship and it was a very smooth voyage. Thank you for this video explaining the vibration.
This channel is interesting. Its more interesting since my son became a 270' river barge First Mate. I got to install a kitchenette in his cabin, my first boat work.
Irish divers in 2008 found and even brought back some Remington .303’s from inside the Lusitania, I think the official number is 173 tons of total war goods.
The ship's manifest listed the rifle cartridges, which may or may not have been suitable for military use. The calibre was in use for sporting and target shooting in the UK. Knowing the type of ammunition would be helpful. Expanding bullets certainly not military, FMJ in belts certainly not civilian, anything else moot. I have seen it claimed that the ship's manifest listed unfilled artillery shells, in which case this was military, but could not have contributed to the second explosion.
In any case, unless the Germans had examined the manifests, the captain would not have known this. He torpedoed a ship full of civilian passengers without giving them chance to surrender, or to be examined. Post hoc justification hardly excuses the war crime.
@@cnocspeireag the .303 was the standard british military round
@@ronalddavisYes, I thought that was Implied in my comment. It was also popular for sporting use. As UK manufacturers would have been fully occupied by military contracts, it makes sense that civilian ammunition would have to be imported.
I have worked aboard trawlers for some time now. I experience this vibration in the vessel I run now, it's a old pre war 1942 Lugger and it is a single screw. I avoid 1350 rpm because it will shake the stern so bad anything back there will slide across the deck. It will also rattle the bow pretty decently but not near as bad. 1400 rpm though, that's butter smooth.
Very interesting video and you present it really well. Thank you.
It's me. One of your biggest fans. Yay! New video!
I clearly remember seeing a TV broadcast in the late 1970's when the famous underwater explorer Jacques Cousteau dived on the Lusitania. It clearly showed that the Lusitania had turrets removed after the wreckage and holds full of ammunition.
we all know that UK government cheat in everything...
I was actually on a catameran ferry last week and was wondering about the vibrations. Always thought it was just the engines themselves. It might well be that the waves didn't mean much to that one in particular, but interesting nonetheless.
Great vid, really interesting...
Very nice video, I really like it !
Bro saw an opportunity in the title, and took it 💀 💀
Early ballistic missile submarines were first produced by basically welding 2 attack subs together. Their 2 propellers interacting with each other's turbulent flow produced a similar vibration problem that could be heard on Sonar.
No, the George Washington class missile submarines were laid down as Skipjack class attack subs, but were cut in half at the bulkhead separating the reactor/machinery spaces from he forward half and had a missile compartment inserted between them.
You worked on a ship? That's so cool, and makes your videos so much richer
Great video, keep it up!
I wrote a history test today and one question was "Why did the USA joined the WW1". Then I went home and saw this video exactly about this ship that was kind of the trigger. Uploading it 7-8 hours earlier would have been better because I could have watched it before school.
actualy the trigger was the telegram, but the reason was the financial aid US banks gave to britain and france who were loosing badly to Us. most americans opposed the war.
The sinking was not the only reason, of course it contributed greatly, especially in changing the opinion of us citizens. The "real" reason for the US to join the War was the interception and decryption of the "Zimmermann- Depesche".
Zimmermann telegraph was by far the main trigger. Lusitania helped ease US public to side with Britain and France but they were still against the war. Zimmermann telegraph was the main thing that decided when US joined the war. The dates back this up as US joined in 1917, 2 years after Lusitania. And Lusitania would not be the first nor last ship sank to have US deaths.
In many other applications, mass dampers are being used to help with vibration. Has this been tried on any ships to your knowledge ?
Great video! Very informative.
I take it that you worked on board P&O's Oriana?
well done! Good video!
You've got an error at 7:47 regarding the date: "In early March..." Two months early: the ship was sunk on May 7.
Both months start with M. Always gets confusing.
Good video. I learned at school that the outrage at the sinking brought the USA into the war, but actually it didn't. It was only the Zimmerman telegraph which revealed Germany was going to assist Mexico to attack the US that led to Wilson reluctantly committing to join Britain.
No, the Zimmermann cable was just an excuse. Lusitania is what changed the public opinion -- which is what allowed the US government to enter the war openly instead of just supporting the aggressors.
(As if there was anything wrong with the Zimmermann cable -- it was a completely justified hail mary pass that happened to fail.)
He mentioned the two-year gap between the sinking and the declaration of war. I think I could hear a hint of sarcasm.
Dude, I love this video's title, "Make Her Vibrate". 😉👍🏻
She really liked it when her stern vibrates💀
I was so absorbed that the end came as a shock.
I like these videos as well.... but there didn’t seem to have a good out-tro to ease the sudden ending shock
Yeah, I remember hearing about a second explosion taking place onboard the Lusitania, and if I recall the book I read about this correctly, I think the british Admiraltly tried to say that the UBoot had used 2 torpedoes, but the captain of said UBoot wrote in his diary that he just used one. The Lusitania's captain was also unfairly treated shortly after the incident by the british admiralty.
Additionally, the sinking of the ship wasn't the turning point that would make the US declare war (that ppint was the Zimmerman telegram) but I agree that it must have been something that brought them closer to it, part in the process of slowly gathering political or popular support for the war.
No, it was a case of "generating" public opinion
I feel like your description on J.P. Morgan was a bit shallow. Yes, he wanted to make profit, but he also wanted to improve the industry. He spoke often about how competing for the blue ribbon was making captains reckless and it was causing accidents. He also believed, based on his other shipping endeavors, that just slowing down a couple of knots would greatly increase the efficiency of the ships and reduce the amount of coal that was being burnt, which would more than triple offset the extra recourses like food that would be needed. He specifically wanted the ships to stop competing with each other for glory and get down to a business mindset of efficiently doing their job. If he had to buy them all to force them to stop competing with each other and increase the safety and efficiency of the industry as a whole, then he would burn every cent he had to do that.
Thanks for covering the other side of the story of her sinking.
Love your video's they are so interesting
It is excepted history that the Lusitania was carrying military munitions. The German embassy in the USA knew what was being loaded onto the ship and tried to warn passengers about the risk and the news papers in America refused to publish the warnings. President Wilson needed an incident to get the support he wanted to join WW1.
Some, not all US papers did indeed print the German warnings immediately below the Cunard advertisement for Lusitania’s May 1, 1915 sailing date. The New York Times certainly did….
@@OrnumCR The White House should have prohibited U.S citizens from traveling on a ship that was a legitimate target of war as it was an active participant of the war since it was carrying military munitions. Wilson was not going to stop U.S. citizens from boarding the ship and traveling into a war zone as he needed an incident to change public opinion on the USA entering the war.
@@opossumlvr1023 …At this quite early stage in the ‘Great War’, certain of those belligerent states that operated liners offered open sailings to and from the United States, and the point of view on the conflict among the general populace in the US was very different at that time so people travelled, regardless of whose ship it was they booked on, and regardless of the cargo the vessel carried. Cunard also stated it had been shipping ‘small arms and munitions’ aboard its vessels from the US ‘for years’ before the war. The cargo the ‘Lusitania’ carried was openly listed on her shipping manifest out of New York. This war was also viewed as a ‘military’ conflict at this early stage and not so much a ‘civilian’ one. The United States also had a very different foreign policy than what it adopts today…one of isolation, and therefore, theoretically free from petty European conflicts. The angle was that the US should have been totally safe in its neutrality and therefore no belligerent side would dare attack any nation’s capital passenger liner carrying US citizens…or so they thought.
Also, much as it does today, commerce and trade ruled, and this lifeline across the Atlantic needed to be maintained. No US government in its right mind was going to stop it’s supposedly safe neutral US citizenry, and the consequential trade they brought, the right to travel the Atlantic as they pleased.
Add in the unfortunate fact that Imperial Germany’s threats before the sinking were seen as bluff and bluster and no one suspected the Kaiser would actually go through with the threat. ‘Lusitania’ changed that.
Schweiger in U20 also never intended to sink such a big, prestigious and well known ship as the ‘Lusitania’, his intention was merely to cripple her, giving her a ‘war wound’ and forcing her in for repairs, thereby inconveniencing her British operator in Cunard. His torpedo and a boiler explosion in tandem ensured the ship’s fate…pure bad luck. He knew the passenger status of the ‘Lusitania’ and was very, very surprised when such a big and well constructed ship as the ‘Lusitania’ foundered from his single torpedo. Sinking her wasn’t his personal intention. Warfare was a lot more chivalrous in those days, a gentleman and an officer would not do such things…etc etc…
Germany’s arguments are also valid. ‘Lusitania’ was openly listed as an armed merchant cruiser in the 1914 edition of Jane’s ‘All the World’s Fighting Ships’ on which Imperial Germany based part of her argument for targeting the ship initially, plus the infamous aforementioned shipping manifest. But Germany also knew ‘Lusitania’ was in open but limited commercial service on the Atlantic carrying American passengers, and in hindsight, perhaps the decision to attack ‘Lusitania’ was somewhat misguided, which, as we saw, proved to be to Germany’s later detriment.
Conversely, Britain was also probably in ‘contravention’ of the accepted ‘rules’ as seen by the German side, but in hindsight, they were probably as bad as each other as rules in war by belligerent nations on all sides often do go ‘out the window’ in an effort to be the victor, in spite of what the general public are told. This is propaganda, and the UK has admitted they did and have withheld important information about ‘Lusitania’ and her disputed manifest on that voyage, which we now know ‘in the nation’s best interests’…
The US is just as guilty of this.
We’ve also personally got the luxury of hindsight on which we’re naturally basing our arguments, but the people of 1915 didn’t know and couldn’t know what was coming and like them you and I cannot tell the future any more than they could. The fate of ‘Lusitania’ was an unfortunate consequence spurred by many unfortunate, and interlocking factors at that time.
@@OrnumCR For a clear understanding of how WWI started read Falsehood in Wartime by Arthur Ponsenby a British MP from that era. The circumstances around the assassination of Franz Ferdinand had the markings of a Communist plot all over it. The Communists gained the most from the outcome of WWI as the Czar and Kaiser were the main obstacles to communist expansion. They hated the Germans as they liked their authoritarian form of government and could not be provoked into revolution as the French had been. The Kaiser offered to end the war while he was winning and return to pre-war borders and his offer was rejected. Germany would have won within a month had the U.S. not entered the war and Germany losing the War makes no sense as none of the battles were fought on German soil. The sinking of the Lusitania could be considered an unfortunate event if it wasn't part of a pattern events that lead the U.S. into wars. The Spanish did not attack the Main, it was a coal dust explosion and we used that event to start the Spanish American war. Washington knew that there was an impending attack on pearl Harbor and did not warn the admirals of the danger as the American people had no interest into getting involved in another European war and needed an incident to provoke a pro war attitude among the people. The official narrative of the gulf of Tonkin does not seem plausible given the weapon systems North Vietnam had at the time. The only way the twin towers fell as they did on 9/11 was if they were set with demolition charges prior to the planes hitting them. The collapse of building 7 which was not hit by a plane fell at the world trade center complex that day had to have been a controlled demolition. If that building was primed with explosives it is very likely the twin towers were also destroyed by demolition charges as well.
@@opossumlvr1023 ….OMG!…what’s all that got to do with the ‘Lusitania’ story?….and shipping? The argument you’ve presented goes off on a completely new tangent. Hahaha….hilarious….well done to you!
"Make her vibrate"
Hmmm...saw dancer that could do that in Cleveland at Christies in '96! Vibrated so much her platform shoe broke 3 stories up! She screamed, I broke chair in half reversing, Brandy plummeted 40', after 3 leaps I looked up, caught her w/face ending at floor, & 8 angry bouncers comin' on to rescue screamin' Dancer! 2 had seen catch, so protected us from horde. Those 2 & Indian Pitcher untangled us, gave me new used chair, & told our money no longer good there. We thought being thrown out...again, but they really meant food & drink for table of five was free! Kool!! We even ordered huge roast beef sandwich for Cabbie standing for us out in lot. Was he surprised! He had been napping, started to gnash snack, clicked on radio, & chatter was about Brandy who had survived 3 story fall. Driver put sandwich, Brandy, and his crazy fares together, & radioed he would have his fares back aboard shortly that had caught Brandy. When stumbled back to cab, driver said thanks for sandwich. Dispatch just radioed no charge for fare or $100 standing fee as Yellow Cab would proudly haul those that saved Cleveland's favorite dancer! Cleveland...What a Town!!!
Great video! Can you do a video on the great lakes ore freighters?
The Lusitania really didn't get the US into the war, that is a myth created later. The reason the US joined the war was Germany trying to convince Mexico to attack the US, which, when found out, the US considered that an act of war.
Also the reason Germany started unrestricted submarine warfare is the UK started to A) ship munitions on civilian ships, which is was illegal, and B) started to arm civilian ships with hidden guns, which was also illegal. The threat of a civilian ship being armed meant the submarine could no longer risk surfacing and giving the crew/passengers time to abandon ship, as the submarine itself could be sunk by the hidden guns.
Everything is a process, there's rarely one single thing that is solely responsible for an outcome. The sinking of Lusitania could very well have been one of many contributing factors in turning both political and popular opinion towards joining the war.
The Lusitania was the keystone of the fear and outrage mongering to get the public emotionally primed. Zimmerman telegram was the trigger pull military excuse to make it official. Muh telegram would have meant a lot less without the outrage porn primer. Since the logical thing to do is prepare to fight Mexico, not cross the ocean.
They like to cast shade, yet the Entante reached a point where they had to force the beast from jekyll island, because they were dented and fragmenting by US entry. Russia was out, France was in thinly veiled crisis, Britain was taking cover behind its Empire and Navy, meanwhile Italy was banging its head against a wall.
Hey. So the Lusitania was sunk in May of 1915, not March of 1915.
Nice, from a vibration 101 video it turned into a Lusitania sinking video. The title is really informative about the content in the video
This might be the best ever title of a historical CZcams video 😂👍
afaik they actualy dived down to the wreckage, and it had i think even ammunition cases in the rump,
also the entente even used red Cross ships as wargoods transports and wihtin thier wreckages were crats upon crates of spent ammunition cases that were transported back to england to be refilled there, which is a very grave break of warfare treateses and a warcrime to use civilians and your own wounded as meatshields for wargoods.
Ok thanks man but can you do a documentaries on the German battleship bismarck and the Japanese steel behemoth yamato?
Please.......
Drachinifel yt chanel got both covered.
Ye because I don't really know much about them and this guys videos are the perfect for explaining it
@@could_possiblybe_thane07echo yea and really he never did a battleship he only did ocean liners and cargo ships I think he should do ww2 related war ships and events like the wilhelm gustoff the worlds most worst maritime disaster in history like only 1000 people survived and 9000 died
@@metalmark9276 wut do u mean?
@@YourlocalNeighborhoodKid there is a you tube chanel called Drachinfel. He covers naval vessels and events. He has videos on both those ships.
Onboard the USS FINBACK, SSN670 ( 637 class sub)
at a flank bell, the hull demonstrated a resonant torsional vibration equal to the shaft speed,
as experienced by a slight rocking motion perceptible in my rack, forward of the screw about 200 '.
It was quite relaxing, especially when headed back to home port
"Making goin' home turns, laddie ..."
What a fantastic video, thank you
On one hand, the Germans fired on a passenger liner that had a very large number of civilians on board. On the other hand, the British were willingly putting their own civilians in harms way by turning the vehicle that they are in into a military target (without the civilians even knowing that they had been made into a target).
The Anglos choosing to keep doing what they were doing after explicit warnings, then using the statistically inevitable fate of civ meatshields to outrage porn the US into involvement when their land war effort is goosed is just plain perfidy; a traditional 10 Downing street gayop if I have ever seen one.
I don't blame the submarine for not wanting to waffle around with the arbitrary British "rules for thee book" that close to the wrong side of the home islands while Lusitania's crew would 100% pull a fast one, like what happened when the Emden was being way too honorable, by ringing the Royal Navy dinner bell on the wireless. Lest we forget, the 10 Downers had consistently proven themselves connoisseurs of going below the belt.
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@@roberternest4641 The
Just got off a P&O ferry Hull/Rotterdam route, that thing vibrated!
I’ve served on navy destroyers and frigates where the same type of thing happened. My first ship it was always around 20 knots and we all called it the 20 knot shuffle. If you were anywhere in the aft end of the ship, you knew what speed she was going when that happened.
You knew exactly what you were doing with the thumbnail
"Why did Lusitania vibrate so much?"
"Propellers."
**proceeds to tell the ship's entire story**
A ferry used to sail from Seattle to Bremerton. It vibrated so much the cream in the coffee shop would turn into butter.
i noticed a vibration on the Hrossey, more noticable when the ship went into reverse. figured it was"blade pulses". there was also a constant rumble noticable where the shafts exit the hull
That title on the thumbnail could be interpreted very differently you know... XD
Anyway, this was really interesting to see exactly how ships suffer from propeller vibration, especially fast ones such as Lusitania. Showing the speed at which the props spin, their positioning in the water and the resulting effects they have on the ship makes it much easier to visualize how this could cause such problems. As an aspiring engineer practicing physics, this is good knowledge. Thanks a lot for another such video. 👍
Also, Brilliant sounds incredibly brilliant _(pun absolutely intended)._ I'll keep it in mind to give them a try at some point.
Most informative video! Could you do a video on hydrojet thrusters? I think those things almost completely mitigate vibrations. Many thanks!
North Carolina class battleships also had vibration issues that prevented it from utilizing its maximum speed , Annoying In a cruise ship , potentially fatal in a warship. Eventually it was ‘ mostly’ fixed
excellent channel, can you do a video on stiff vessels vs. tender vessels?
the title card got a chuckle out of me
I don't have any particular interest in ships, but I still enjoy watching your videos 😬
I used to cruise on a ship that suffered stern vibration during engine changeover whilst synchronisation took place. An interesting experience!
My dad was a saturation diver for a salvage company in the 80s and 90s. He went to the Lusitania and brought back 2 small detonators which still live on his bookcase. He didn’t say whether he found them in the refrigerated section or not!
Cool! I worked with modal responses most of my career. My first cruise, I bugged my family by talking about how you could measure the side to side frequency response of the ship.
Folks, I was on the Norwegian Cruise Lines "Escape" in April and we had the last cabin on the port side on deck 9, so we were at the stern. I mean to tell you the glasses rattled all the time! There was vibration like crazy on this boat! This was the first cruise of this boat after the grounding incident in the Dominican Republic, and I think it has a bent propellor blade. Even in the buffet, we are sitting next to the aft window and the ketchup bottle is sitting there wiggling as we ate! I didn't have any problem sleeping, it wasn't that bad, but it was DEFINITELY noticeable! It is normal to feel vibration, especially at the stern on a cruise ship when you come into port and they reverse the electric Azipods that actually drive the ship; But on Norwegian Escape it was all the time! I will say that the ship is amazingly well designed, we had a GREAT time, and there was no vibration elsewhere. But they cancelled and curtailed two of our stops, supposedly because the sea current wasn't going to allow us to get there, which is of course BULLSHIT. In general, Norwegian isn't as well organized as Royal Caribbean, which is superb. But that ship was WAY better than Celebrity's Equinox, Royal Caribbean's Freedom of the Seas, and Cunard's Queen Victoria.
By the way, Cunard? They are now owned by Carnival Cruise lines, the "Wal Mart" of the waves....
The resonance bit is fascinating. One thing I'd ponder is if it's about the frequency at the ship's normal cruise speed matching the hull's resonant frequency, could they have remedied this by installing propellers with a different number of blades to change the blade frequency for the same speed and RPM? (The propeller would have say four blades, but they'd be smaller, and the pitch of the blades would be the same so they'd be the same power and RPM for the same speed.) Or perhaps three blades on the inboards and four blades on the outboards, or vise versa, so the blade frequencies wouldn't be in sync?
It's always interesting to see places that resonance can come up. I have a bicycle trailer, one intended for carrying a child, that my roommate and I used to haul groceries to our apartment in college - surely exceeding its 100lb capacity rating on a regular basis. Instead of a universal joint, it had a flexible spring coupling it to the bicycle. At certain pedaling cadences the power pulses would match the resonant frequency, and the trailer would surge back and fourth violently. But if you managed to continue accelerating through that, it would stop once going faster.
Old liners look cool
Propeller Balance and blades being out of track is the #1 and #2 factors of ship vibration. Always has been always will be. I've been repairing and manufacturing ship propellers since 1996.
I've seen people try to figure out why their little ski or fishing boats were getting slower and vibrating more, yet look at me like I was stupid when I said that props should be intact, smooth, and shiny, rather than all chewed up and fouled with marine growths.
It's bad enough at 100 turns on a ship, but far worse when you try to spin a damaged 12" prop at much higher RPMs.
@@kevincrosby1760 speaking of Marine growth, this weekend I get to spend in the shipyard cleaning a 32 foot diameter prop from a ship from Military Sea lift command. They sit anywhere from 3-5 years and need to be debarnacled. It's friggin man work.
@@mikebrase5161 Almost like the little critters are designed to be hard, sharp, and firmly attached to discourage predators.
The ocean is a dangerous place for the critters which live there.
I actually lived in one of the towns on the River Clyde between 2015 and 2020, so I saw a fair few Cunard ships going past. I even boarded a small one once because it replaced a damaged passenger ferry for a few weeks! Never got the name and I can't comment on the service unfortunatly, I have Thaslasophoba so I was bit pre-occupied with trying not to freak out. Still nice to know I sailed with a historic shipping company.
As a former crew member of the RMS Queen Mary 2, she did act as a Royal Mail ship as she had a Royal Mail postbox/mailbox on board
Later ships with 4 propulsion shafts used different props on the inner and outer shafts. I.e. the inner props have 5 blades while the outer props have 4-blades. This difference greatly reduces the vibration because the inners & outers induce said vibrations at different frequencies, thus cancelling out. The issues experienced by the Lusitania and her sister ships became lessons-learned and applied to future ships. If you really want to see this in detail, check out the various battleships, built in the '30s and '40s, especially the American fast battleships.