The Proximity Fuse - Secret Weapon of World War 2
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- čas přidán 14. 10. 2012
- The VT Proximity Fuse. This was a highly classified invention of World War 2, which enabled bombs and projectiles to detonate at a set distance from the target. Greenfield's wartime production included a manufacturing plant for these devices. The surviving residents, who once worked at the plant, were not explained the purpose of their efforts until the 1980s. The Museum of Our Industrial Heritage has examples of actual devices and components on exhibit for our visitor's appreciation.
visit our museum at industrialhistory.org - Věda a technologie
Mt father operated a drill press on the night shift at a defense plant in Silver Spring, MD. After WWII, he found out he was working on the proximity fuse.
I got to view one in the Admiral Nimitz Museum in Fredericksburg, Texas. Rather interesting. It was an amazing technological accomplishment in that Era. The physical stresses on the several electronic tubes were horrific from the acceleration in the cannon and then the rotational speed as the projectile traveled to target.
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These electronic fuses were used in the Pacific with devastating effect on the Japanese aircraft. They were so secret that for a long while they were used only over water in case one fell to ground without exploding and might discovered by the enemy. It was a clever idea to use the shock force of being blasted out of a cannon to break the little glass vial containing acid so it splashed down into the dry lead battery plates. This activated battery needed to operate only for a few minutes until the projectile neared its target. There was supposed to be a self destruct mechanism in case the fuse was never triggered by any target.
The fact that this delicate and sensitive device could be shot out of a gun at hundreds of gs and work perfectly is even more amazing than the timed fuses on atom bomb.
Being an old Marine Artillery Operations Chief ( 0848) I can say that shooting a VT fuse at a target works great...
I wonder if there were really lots of people that sounded like that or if this guy just made a good living narrating these films all over the US.
I think that was a style of radio speaking back in those days and it probably had a lot to do with the frequency response of the audio equipment in use back then.
I've been thinking so too nice
My father Martin Kesler Sr. was a dye (color) chemist and also worked on the polaroid sun glass plastic color in the nose cone of the VT fuse, which had trouble in the sun light. He further worked on the first polaroid land camera and the sun glasses use of the same color.
I honestly had no idea. That was one hell of a thing to invent and make en masse during that era.
To consider the value of the proximity fuse for antiaircraft fire look at the sinking of the Bismark. The death knell was set when swordfish torpedo bombers damage the Bismark's rudder. The antiaircraft fire was ineffective because the timed fuses were preset with the firing order locked into how the reload ammunition was readied.
The first were timed to explode at a certain distance which would be the initial firing. From there the shells would exploded progressively closer to the ship as the aircraft came closer. But the Swordfish was an old biplane model and slower than the German gunners expected to face. As a result many shells exploded harmlessly far in front of the Swordfish and the Bismark suffered loss of it's steering ability sealing it's fate.
To get the miniature vacuum tubes for the fuses they looked to existing technology. Vacuum tubes for hearing aids. Hearing aids of that time were a box worn on the belt with a wire to an ear piece. This was the model for the tubes for the fuses.
I believe such a fuse was also used on the first atomic bombs.
The proximity fuse was one of the best kept Allied secrets of WWII. A significant technological breakthrough to make antiaircraft fire even more deadlier ! 🇺🇸 🇬🇧🇨🇦 👍💥💥
The Germans invented it
I find it interesting that to this day, VT or Variable Time, is used to describe this fuzing, even though the secret has long been out.
The timed fuses must have been difficult enough to design and manufacture. On the fighter-launched rockets, both circuits came into play as the proximity circuit didn't become armed until almost a second after firing, to protect the launching aircraft itself. So, you needed both circuits to function as designed. Amazing that we could manufacture this stuff in quantity and be expendible. Of course in wartime, cost suddenly becomes of no consequence; future generations are left with the tab!
Waterbuty Clock of Connecticut, in business since the 1850s, made fuze timers during that war. Waterbury evolved to become Timex, one product of which you may wear on your wrist. Takes a licking, and keeps on ticking.
Thanks for keeping record of such valuable video.
this was such an amazing revolutionary fuse, yet in Vietnam when the mud season hit ,soldiers would complain shell damage would be absorbed from the soft ground impact. and my grandfather was in artillery in the late 40's 50's and said he never used the prox fuses just the timed ones. why did we stop using these fuses after ww2 they worked so well
Interesting video, thanks for sharing :-)
What great post. thanks
Wow, that sure put a damper on his day, huh. 6:34
So many modern conveniences that the public takes for granted derive from war time innovations. Medicine, electronics, pressurized aircraft, the internet, etc.
What for do you use proximity fuses and TNT in your home?
@@freggo6604 - One type of fuzes used light instead of radiowaves (or at least there was the idea of them - Churchill mentions it in his memoirs). That photocell is used in modern public pissoirs. Not at home, but still a peaceful kind of use.
Is the new fuse time delayed not to be set off by the barrel of the gun ....if that makes any sense ? Also when dropping a bunch of bombs at once ,how come the signal is not reflected off the neighboring bomb prematurely???
Never loose the technological edge.
Or lose it, either.
Very recommendable
I always thought they had a little mouse trying to get a piece of cheese who tripped the explosive.
Some of the drawings here are a bit misleading. In the frame of reference of the moving munition the fragments spray out to the side. Correct. However the munitions are moving faster than the target (if it's an airplane) and of course the target could be utterly motionless. In the frame of reference of the target the fragments occupy a cone-shaped region with the tip of the cone being the point of explosion and the cone extending forward of that point. This is particularly true of artillery rounds; not so much for the slower bombs.
Question: Why didn't clusters of VT-fuzed bombs end up detonating one another? Was a bomb casing too small a target to create the required signal reflection?
Russ G cluster munitions and similar weapons have a 'safe to arm' delay to prevent 'fratricide' while they are still close.
they would also be operating on different radio frequencies. Each lot of fuzes would have each fuze using differing settings so you couldn't mix fuzes from different lot numbers or they might set each other off.
I remember well, a proximity fuse triggering a shell as it left the barrel on our destroyer, massive explosion 10 metres from the gun. I thought they were on our side?
Thanks for your service. When and where did you serve?
In the ordinance usage, it is usually spelled 'fuze'.
Nice of them to also credit Canadian and British scientists. Modern USA documentaries would have us believe the USA did almost everything. The USA was a manufacturing giant but many countries were more advanced scientifically.
CG Account
Modernization of the education in western countries have been focussing less and less on context and more and more on facts
I as a biology teacher hate it
The pupils often believe leftist parties to automatically have the best interests of the environment and immigrants
Me as a teacher allowed myself to shake these pupils into a state of awareness when I tell them the context
But the majority of the pupils still call one another stupid when one speaks up about something a bit different then most believe to be true.
Such as the Dutch fighting the Japanese in WW2
The Dutch were one of the first to be attacked by the Japanese but the other pupils just said things along the lines of "are you stupid? The Netherlands are a small European nation"
Not even seeming to consider that they still had colonies in 1939
@@joeviking61 Britain also gave away a bunch of jet aircraft technology to the US right after WWII, and both rocket technology and air-to-air missile technology a couple of decades later.
joeviking61 Sounds you need to do some reading. The German 88’s has no equal. We had no such weapon that would penetrate the Maginot line turrets at 1.5 km.
William Chamberlain That they got from Germany.
I understand all the theoretical work was completed in the UK and communicated to the US for industrial development by the Tizard Committee in 1940. Hardly just a few ideas. Rather typical, I fear.
Yes. Rather typical how the British automatically assume full credit for everything.
en.wikipedia.org/wiki/Proximity_fuze
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I've heard that the US Artillery started to use VT Fuze just before the Battle of the Bulge.
This type of weapon is also devastating for the German Infantry in entrenched areas and were willingly to give up if their defensive positions were exposed to American Artillery Fire that cause mass losses among German Troops.
Also in the Battle of Britain, the British Anti-Aircraft Command also used the same shells to counter V-1 Rockets with the combination of fire-control computer systems and radar.
Is this what's also referred to as flak?
My aunt worked during WW2 in a secret room in downtown Worcester MA, making very small tubes with 4 or 5 other women. So far its never been confirmed what company it was. Best guess was Raytheon. Likely only her SS records will confirm! She described to me ( before she passed on) what she was actually was doing in the assembly room. Is it possible the section in the Utube video here is in that room of women?
Secret Service
Living in Edge
FUZE
since they use radio waves, can they be jammed so that they explode as soon as they leave the gun?
U'd have to know the enemy gun position first, which is several km away. Also pretty sure the fuzes have encryption of sorts to prevent this.
@Michael Colapietro we have jamming sets for those now, basically our ECM sets would overload the receivers so that they couldn't hear their own frequency and would hit the ground before detonating. It's how we keep radio-controlled IED's from going off.
@260830107 the fuse doesn't arm until several seconds after it gets a kinetic shock of a certain level of gravity, caused by it being fired. Mechanical safeties using springs, pins, bb's machined incredibly small back then, nearly microscopic now.
What is the average velocity of the schrapnel!?
How ever fast the Shockwave of the explosive is so for tnt like 6000 m/s
good video having too much knowledge about fuze its use and history...
I finally understood how different bombing became after ww1
I had a few of these proximity fuses from some shells my grandpa took from
IT was it was a blighty thing,a bighty blighty thing.
The VT was so under appreciated. I believe the records now show that a large portion of the kamikaze planes shot down in the pacific were due to these, and the ship commanders once they were told or found out about these magic shells wanted nothing else. And the percentage of hits versus shots fired were like 7 fold better than dumb shells, incredibly valuable against UK v1 attacks also, and then battle of the bulge attacks as the VTs were set to go off just above the ground and did great damage over a much large radius than a ground impact would.
Interesting... is this still being used today in 2018?
Yes, but they use semiconductor devices, instead of vacuum tubes.
They have a number of different things they do today - but just as this was a big secret during WWII - exactly how what they are doing today works - the people who really know - can't say. What I have to say here - is from published commercial sources (like Jane's) since I don't really know myself.
There is a variation on what is described here. Here - you have something emitting radio waves - (which is what radar does) - and as soon as it gets a bounce back - it goes off. There are radar guided missiles - where the missile is continually tracking it's proximity to the target (making multiple calculations per second) and trying to close that distance by adjusting it's steering. IF the missile detects that it is no longer getting closer - but rather is getting father away - it goes off.
So - in the case of the VT fuse - it detonates at a specific distance from the target. In the case above - it keeps trying to close - and will hit the target directly if it can - but if it calculates that it isn't getting closer any more - it goes off as close as it was able to get.
Different systems use different tracking. Some of them use infra-red. Some of them may use multiple methods. Since the radars on these missiles are not as powerful as, say, one on a ship - often the ship will provide initial tracking - but - once the missile gets close enough for it's own radar to work - it will take over and the ships fire control radar - will go work on another target.
During the Christmas Bombing of 1972 during he Vietnam war - the US jammed the North Vietnamese radar systems - so that they couldn't get a lock on the B-52's. The US had been reluctant to use this technology - as it was part of their ability to do nuclear strikes on the Soviet Union - and once they know you know how to do something - they can work to counter it. But - the US was dedicated to making the Christmas Bombing work and the B-52's needed this jamming to avoid all getting shot down.
What the North Vietnamese did (possibly under Soviet Guidance, though possibly not) - was to just start shooting the AA Missiles up into the air where they thought a B-52 might be as they did have such as sound detection systems (as was used in WWII before radar and as a back up after it). If the missile got close enough - it's own radar could detect a target and it would go after it. The Americans were all approaching their targets from different directions (at night) - but - when they came OFF the target - they were doing it the same way each time. The Communists figured that out - and began shooting their missiles up into that area - and the US lost a number of B-52's. Then the B-52's stopped doing that - and the Communists were stuck. In the end - they had expended ALL of their AA Missiles and were defenseless against the B-52's.
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The Proximity Fuse is really a potable radar; a British invention.
That's very informative; thanks!
yeah but we put in a shell.
i mean it's like saying the M4 sherman was a british tank because Britain first designed the tank.
British invention with significant design enhancements in the USA
Well, half and half.. The Brits didn't have the industrial might, and American know-how was available in great quantity. So they did what any country that had a secret weapon but no real way to mass-produce or innovate it, haul it to your neighbor and ask for assistance. MIT's Radiation Lab was the place to be during those times, creating miracles from the cavity magnetron, turning it into the SCR-584 RADAR set that withstood the test of time, and are still in use in locations like China Lake, and the National Weather Service.
The British invention was the cavity magnatron which was the foundation for all the radar innovations. The Germans had nothing like it.
The Brits did not have the resources at that time to exploit the technological edge the magnatron had given them. However, it was the MIT Rad Lab that put the talent and the money of the US taxpayer that made radar one of the essential developments that helped win WWII.
The proximity fuse to me was one of those incredible developments. As radar sets went the VT fuse was a simple device compared to radars that were installed in ground stations, ship, submarine, and aircraft.
The VT fuse was really more like a burglar alarm wired to a blasting cap that could withstand the acceleration of an artillery shell. It was a very clever design considering the technology available in the early 1940s.
Military science tricks
Sorry British scientists invented the VT fuses and they gave the idea to the USA to manufacture it.
Also the magnetron.
I do wish Americans would give credit where credit is due
The US also took over two years to enter war, and only when attacked by Japan.
This film does give credit to the British.
DigNap15
Did you watch the video?
Why is that US clips, such as these, create an image of an American invention, when in reality it had been proposed and in development in the UK long before?
Question for those that know more about this, would the fuse be defeated, prematurely detonated, by the enemy if they could broadcast a strong radio frequency that the fuse was expecting to 'hear'?
Yes, which is why they were kept so secret and initially only used where dud shells would not likely be retrieved by the enemy for study. Only very late in the war were the used over enemy troops. It was a very primitive setup, a low power transmitter carried by an enemy aircraft of the correct frequency would render it ineffective. The secret fell into the hands of soviet spies and ironically a more advanced version was used in the rockets used to shoot down Gary Power's U2.
Yes. An example of something similar was the German Fritz X Radio Guided Bomb
en.wikipedia.org/wiki/Fritz_X
This weapon was used to sink one of the Italian Battleships surrendering to the Allies and then used against the ships off Anzio. However - the Allies gradually figured out which frequencies the Germans were using to guide them in - and then just jammed them - causing the missiles to tumble from the sky when they lost guidance.
Another incident that may have had similar factors involved was the death of Joe Kennedy, JFK's older Brother. He was supposed to take off a B-24 packed with explosives - and bail out. The Aircraft would then be flown to and then into a target using radio control. About the time he and the flight engineer were supposed to turn on the radio controls (which could detonate the explosives too) the plane just blew up. They don't know why as the biggest piece of it found was one of the wheels but there is speculation that a radio broadcasting on the frequency used to detonate the explosives caused the premature detonation. There was never any speculation that the Germans had done this - but rather that it was just a stray signal.
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Die Geschichte ist süß! Der Transistor wurde erfunden 1947, er wurde nicht ab 1942 eingesetzt. Für das elektrische Feld brauchte man Röhren mit Heizspannung 6 V und Anodenspannung, 200 V. Dazu eine Batterie mit 150 Zellen und eine andere Batterie mit 4 Zellen. Auch die Senderöhre ist groß. Im Gehäuse ist kein Platz.
Beim Abschuss wird aufgeheizt. Die Röhre ist arbeitsfähig nach mindestens 2 Minuten. Mittlerweile ist das Flugeug weggeflogen.
Ich vermisse die Sendeantenne, nötig für das elektrische Feld.
Natürlich wirken Kräfte von 20000 G und 5000 G (radial) auf Röhren und Batterien.
... und die Erde ist eine Scheibe.
Completely ignores the fact that the Brits were working on these fuses first and came up with the idea - only when they order miniature valves off the Yanks did the Yanks suspect they were working on something like this and started making their own.
_”3 score...”_ ? People still said ‘score’ in the 1940s?
The days of our years threescore and ten... people still read the Bible back then.
Too bad the video is so dark...
AMERCIAN MADE!!! (with with a tad of British help).
i don't see the apparently fabled "german engineering" coming up with this in ww2.
Sounds more like British Made! with some important help by the US.
Wow, Americans really can't help themselves. It was fully conceived by the British. You're welcome, BTW.
It's a shame our world has to devote talented resources to build and use these things against each other. If not for this stuff and religion, we'd be to the stars by now.
How horrible