Hi Milt,
I've not heard of those types of 'crash switches', but I do know of a similar system that fires off when any of the mercury switches are broken.
The Lockheed P3C Orion aircraft has several mercury switches fitted, one at each wing tip, a couple in the nose and a couple more in the dry-bay in the fuselage in the wing center section, that will fire off the emergency locator system when broken/crushed.
They have a unique little battery operated locator beacon fitted to the RHS of the vertical stabilizer which will 'spring' out (strong spring) into the airstream, water or onto the ground instantanously when triggered. It's even been shaped like a leaf (sort of), so it will flutter down to the ground if needed, or float on the water, transmitting for a very long time.
Just thought it rated a mention,
Cheers, FD
