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In testing the windshields of airplane cockpits, one must be sure that the windshield can resist the impact of the plane smacking into a bird at top speed. So, in order to test this, at least one company built a compressed-air cannon to fire frozen chickens at airplanes. The footage of this is really quite astounding, but not for the squeamish.

First of all, let me say that I don't know if this story is true. But it's so fucking ludicrous...

The Federal U.S. Aviation Administration set a webpage describing one of his more ingenious devices. It was a device to test the resistance of the glass of the of airships and consisted of a tube that shot a dead chicken to the windshield of the airplane. The firing was exact and reproduced the speed with which the bird would reach the airplane in flight. Theoretically, if the windshield resisted the test of impact, then it certainly would support a collision with a bird in a real flight. Actually, the device worked perfectly, with hundreds of tests conducted in the USA.
Engineers of the RENFE (Spanish train company) who were developing a new high speed train found the website and were instantly interested in the “chicken cannon”, thinking about applying the idea to test the windshields of its new hi-tech train in final phase of project. They entered contact with the US-FAA, obtained a lent cannon and they came to carry out tests. Already in the first shot, the chicken burst the frontal glass of the train, broke the panel of instruments and the chair of the engineer, hurt two technicians and flew until the bottom of the locomotive, crashing in the back wall and leaving a deep hole in the plate. The Spaniards were completely perplexed with the surprising and violent result. They documented the scene in detail, they produced digital photos, they recorded declarations of eyewitnesses, they drafted technical documents and they sent all the information to the US-FAA via email, asking what was what they had done badly. The American technicians studied the received documentation carefully and responded, in a dry and direct email:

"UNFREEZE THE CHICKEN”

Clarification time: the chickens had better not be frozen at the time they're fired from the cannon.

There's a story1 attached to this. Some (but not too many) years ago, British Rail borrowed a chicken cannon from the folks at BAe for the purpose of testing the windshields of the new high-speed trains. They dutifully followed instructions, setting up the cannon and loading it with supermarket chickens.

The first chicken fired completely shattered the windshield and embedded itself in the aft wall of the engineer's compartment.

Seeing this, the train guys called up the aerospace guys who had lent them the cannon and described what had happened. They got the following response:

"Did you thaw the chickens first?"


Incidentally, there are at least two models of chicken cannon in use in the aerospace industry. The first, described in the original writeup, fires single chickens weighing up to 8 pounds, to simulate the impact of one large bird. Another model can only handle birds up to 2 pounds (Cornish game hen time), but it can fire 8 or so of them in the space of 5 seconds, to simulate a flock. Yes, it's a chicken machine gun2, or its nearest equivalent.

In addition to testing windshields and other structural elements, chicken cannons are standard testing gear for turbine engines. A bird (or flock) sucked into a jet engine is a Bad Thing if the first-stage compressor blades aren't designed to withstand the impact.


1Okay, so this has been revealed to be an urban legend.

2In my college days, I often wanted to introduce this into a Paranoia campaign as a weapon, but I couldn't justify the existence of frozen chickens in Alpha Complex.

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