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V2 rockets on London and surrounding counties

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Re: V2 rockets on London and surrounding counties

#11
Such maps always remind me of this polandball joke: https://commons.wikimedia.org/wiki/File:Blitz_map_of_London_...

This episode of Dan Carlin's Hardcore History podcast shows how civilized societies could justify to themselves to do fire or nuclear bombing: http://www.dancarlin.com/product/hardcore-history-42-blitz-l...

Re: V2 rockets on London and surrounding counties

#14

Just visited DC area, USA and went to the Smithsonian Air and Space museum. That have a V2 on display there. It gives one a palpable impression of their power especially in WWII.

There's also one on display in London at the Imperial War Museum near Lambeth North. I'd read a lot about them, and seen pictures, but it was still far bigger than I expected.

Re: V2 rockets on London and surrounding counties

#15
post #3

WOW I had no idea how many landed in London. I always thought that they were inaccurate and weren't effective. Sure would have terrorized me and came close to Big Ben.

Note the note:

> This map is not comprehensive. Many strikes in open countryside are omitted. And many strikes in the East End of London are missing due to lack of concrete information. Please leave a comment if you have evidence.

There were 1358 fired at London, FWIW.

Re: V2 rockets on London and surrounding counties

#16
post #3

WOW I had no idea how many landed in London. I always thought that they were inaccurate and weren't effective. Sure would have terrorized me and came close to Big Ben.

Good thing they didn't have any on-board guidance systems back then.

The V2 used pendular integrating gyroscopic accelerometers (PIGAs) and gyroscopes for guidance. As far as I know, the V2 was the first use of the PIGA. Descendants of the V2 guidance systems were used by the Apollo moon missions and several US intercontinental ballistic missiles.

The PIGA is actually a pretty cool piece of machinery. You have a free-swinging balance arm that has a mass and a gyroscope on it. The gyroscope's axis of rotation is aligned with the balance arm. An electric motor spins the whole balance arm in a direction perpendicular to both the gyroscope's axis of rotation and the axis about which the balance is free to rotate. So if you remember from Freshman physics, you have a rotational momentum and an applied torque, the resultant torque is the cross product of the two (in other words, a torque in the direction the balance moves freely). An analog controller keeps the electric motor spinning at a rate that keeps the balance beam level. So, the rate the electric motor is turning is proportional to acceleration in the direction of the electric motor's axis. Thus, the integral of the acceleration is proportional to the integral of the rotational velocity of the electric motor. In other words, the number of revolutions of the electric motor is proportional to the velocity of the rocket (relative to free-fall). A simple revolution counter is sufficient to cut off the engine's fuel flow once the rocket has reached a given velocity.

(Source: I interned at Draper Lab, which made the Apollo guidance systems and several ICBM guidance systems. I walked by an Apollo PIGA in a display case every morning.)

Re: V2 rockets on London and surrounding counties

#17

Interesting as I've recently started re-reading Gravity's Rainbow, again, for the third time.

I've just started reading it for the first time. Combined with some of the recent Blitzkrieg-related links that have been posted to HN, it's really affecting me.

Re: V2 rockets on London and surrounding counties

#18
post #16

Earlier quoted context omitted.

Good thing they didn't have any on-board guidance systems back then.

The V2 used pendular integrating gyroscopic accelerometers (PIGAs) and gyroscopes for guidance. As far as I know, the V2 was the first use of the PIGA. Descendants of the V2 guidance systems were used by the Apollo moon missions and several US intercontinental ballistic missiles. The PIGA is actually a pretty cool piece of machinery. You have a free-swinging balance arm that has a mass and a gyroscope on it. The gyro…

Fascinating. Thanks for sharing.

I meant in terms of GPS-based which would improve the accuracy. Sorry for being a bit flippant with my original comment.

Re: V2 rockets on London and surrounding counties

#19

Just visited DC area, USA and went to the Smithsonian Air and Space museum. That have a V2 on display there. It gives one a palpable impression of their power especially in WWII.

Also one at the Kansas Cosmosphere for those in the midwest. They also have a similar map : http://www.v2rocket.com/start/others/006-ks2001.jpg

From restoration photos found at http://www.v2rocket.com/start/others/kansas.html

Re: V2 rockets on London and surrounding counties

#20
post #3

WOW I had no idea how many landed in London. I always thought that they were inaccurate and weren't effective. Sure would have terrorized me and came close to Big Ben.

Interestingly, the British used double agents to trick the Germans into targeting V-1 and V-2 rockets away from Central London by selectively reporting impacts and adjusting impact timestamps to make them believe that the rockets were overshooting their targets when they were, in fact, falling short.

https://en.wikipedia.org/wiki/Double-Cross_System#V-weapons_...

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