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From: jgpo@ihu1e.UUCP (John, KA9MNK)
Newsgroups: net.aviation
Subject: Control surface failure
Message-ID: <348@ihu1e.UUCP>
Date: Wed, 28-Nov-84 12:21:22 EST
Article-I.D.: ihu1e.348
Posted: Wed Nov 28 12:21:22 1984
Date-Received: Thu, 29-Nov-84 04:36:16 EST
Organization: AT&T Bell Labs, Naperville, IL
Lines: 33

< CLEAR! >

The other day a buddy of mine at work was telling me of a trim tab failure
he had in a Traumahawk.  It seems the trim got stuck full aft and he nearly
demonstrated a classic departure stall.  He got it down OK, though, and
consigned the plane to the tender mercies of the friendly neighborhood A&P.
While the mechanic was tearing into the guts of the plane, my friend asked
a CFI what would have happened if, say, the failure had involved the elevator
instead of the trim tab.  The answer?  "Well, we'd have to write a report..."

He told me this and, naturally, this prompted a long session of hangar
(office?) flying.  We tried to figure out what would happen if one or more
control surfaces failed, subject to the constraint that the failure would
result in the affected control surface streamlining with the relative
wind, i.e., a severing of that surface's control mechanism without it getting
stuck.  For an aileron failure, both ailerons would streamline.

We decided that a rudder failure probably wouldn't be too bad.  An elevator
failure would be pretty tense, but the plane might be flyable to a controlled
crash using trim.  An aileron failure would be extremely bad news, but a
good pilot *might* be able to survive the crash by trying to keep the wings
level with fast and furious rudder work.

We didn't even want to think about multiple failures.

Does anyone have any ideas on the subject?  Or worse, any experience with
control surface failure?  This could be an interesting subject for
discussion, so why not post your replies?


	John Opalko
	AT&T Bell Labs 
	Naperville, IL