Engineers at a major aerospace company were instructed Io test the effects of bird-strikes on the windshield  of airliners and military jets. To simulate(D the effect of a goose  _ an aircraft traveling at a high speed, the test engineers built a powerful gun, with which they fired dead chickens at the windshields. The simulations using the gun and the dead chickens worked extremely effectively, happily proving the suitability of the windshields, and several articles about the project appeared in the testing industry press. It so happened that another test laboratory in a different part of the world was involved in assessing bird-strikes--in this case on the windshields and the drivers' cabs  of new high-speed trains. The train test engineers had read about the pioneering test developed by the aerospace team, and so they approached them to ask for specifications of the gun and the testing methods. The aerospace engineers gave them details, and the train engineers set about building their own simulation. The simulated bird-strike tests on the train windshields and cabs produced shocking results. The supposed high-speed train windshields offered little resistance to tile high-speed chickens; in fact every single windshield that was submitted for testing was struck to pieces, along with a number of train cabs and much of the test-lab itself. The frightened train engineers were concerned that the new high-speed trains required a safety technology that was beyond their experience, so they contacted the aerospace team for advice and suggestions, sending them an extensive report of the tests and failures. The brief reply came back from the aero-engineers: "You need to defrost   the chickens... " The train engineers' tests failed because
the trains' speed was too high the train windshields were not hard enough the testing methods were not suitable for the train they didn't defrost the chickens before firing them