"Apparently" this is a true story.
During the late 60's, scientists at Rolls Royce built a gun specifically to launch dead chickens (at high velocity) towards the windshields of airliners and military jets. The concept was to simulate collisions with airborne fowl to test the strength of the windshields. American engineers heard about the gun and were eager to test it on the windshields of their new high speed trains. Arrangements were made, and a gun was sent to the American engineers.
The gun was set up and the first test performed, when fired, the engineers stood in horror as the chicken hurled out of the barrel, crashed into the shatterproof shield, smashed it to smithereens, blasted through the control console, snapped the engineer's back-rest in two and embedded itself in the back wall of the cabin like an arrow shot from a bow.
The horrified Yanks sent Rolls Royce (along with the designs of the windshield) the results of the disastrous experiment, and begged the British scientists for suggestions.
Rolls Royce responded with a one-line memo:
"DEFROST THE CHICKEN FIRST"
