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Peter

As is the case with most funny tales this one has a central truth.  Who
knows maybe the one you told is the correct one and this story is the
descendent folktale.

Several decades ago when Lear was certificating the original Lear Jet (now
Bombadier, a proud Canadian company) the US aviation industry had just gone
through a spate of in-flight bird strikes.

Recently my son, while flying fisheries patrol off the coast of Washington
state, had a Bald Eagle challenge his airplane head on.  The eagle passed
within a wing span of my son's airplane.  My wife while flying in Virginia
was challenged by a large bird which again passed within a wing span.  Bird
strikes are a very serious problem within the airplane industry.

Any way, the FAA required that Lear prove (absolutely prove not just show
engineering data) that the windscreen in his new jet would survive a
Canadian Goose strike at speeds of 250 knots. (The speed most jets are
flying during  a low level approach to an airport).  The designers at Lear
conferred about how to make sure a bird would strike the airplane in flight
and had about given up when one bright young engineer suggested shooting a
dead bird from an air gun at the wind screen.  Needed one dead bird
approximately the size of a Canadian Goose.  A dead chicken volunteered and
was fired from a rigged up air gun.  Sure enough the chicken achieved 300
knots.  The FAA was asked to ceritify a dead chicken as an acceptable
substitute for a Canadian Goose and another volunteer was found to be fired
at the windscreen.  The windscreen survived.  In the typical unconscious FAA
fashion the FAA then asserted that since no engineering data on the chicken
strike had been provided only that particular windscreen was certified
against bird strike.

Currently all new Bombadier jets as part of their airworthiness check have a
dead chicken fired at the windscreen at 300 knots from the same gun.

The Bombadier chicken air gun has been copied and is in use at a number of
aircraft manufacturers.  It is now the accepted method of proving jet
aircraft windscreens against bird strike.

Rick Seddon
McIntosh, NM