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From: Mary Shafer <shafer@reseng2.dfrc.nasa.gov>
Newsgroups: alt.aviation.safety,rec.aviation.misc,rec.aviation.military,
	alt.disasters.aviation
Subject: Re: AVIATION SAFETY ISSUES in AAS
Date: 13 Jul 1998 10:43:46 -0700

elysium@iafrica.com writes:

> I'm a bit out of touch with light GA aircraft of late, but I seem
> to remember there was an A.D. precluding spins in Cessna singles a
> while back. Vaguely remember a P.O.H. change and a decal affixed to
> the flight panel prohibiting such ( seem to recall it was about
> 'product liability era' ). Could this have been behind the
> moratorium ?

No, it was a change in FAA thinking.  As I recall, the idea was that
rarely does a pilot get into a spin high enough to recover, as most
stalls and departures happen during takeoff and landing, not cruise,
and don't develope into spins before ground impact.  There was a
constant trickle of people dying in spin recovery training and the FAA
decided that it was better to teach pilots not to depart their
aircraft than to keep killing a few of them every year teaching
something that wouldn't help in real life.

Many people, particularly those who had spin recovery training, think
that this is a short-sighted attitude on the part of the FAA, but
there hasn't been any significant increase in the number of people who
die in non-training spins and there has been, obviously, a significant
decrease in people who die in training spins.  I think that the number
of people stalling and departing in the pattern has reduced, but not
to zero.

> Is it possible that Commercial and Airline Transport Pilots may
> have got their tickets without performing any practical spin
> recovery training ? If so, is it a genuine concern ?

Yes, it's possible.  No, it's not a concern.  When's the last time you
heard of an airliner spinning in?  It just doesn't happen.  Stalling
on takeoff and falling back onto the runway, maybe, but only very
rarely.  That's what stickshakers are for.

They don't even spin-test the aircraft during certification.  The only
thing they test is whether the airplane gives a distinct clue to the
pilot that it's stalling.  That is, it needs to drop a wing or
something, not just mush into a stall.  The (Canadair?) Challenger had
to add a metal tab on the leading edge of one wing to get this
distinct cue as the airplane originally just mushed straight ahead in
a stall; the other choice was to put a stickshaker into the plane,
which would have been more expensive and complex than was practical.
The F-17 stalled the same but adding a stickshaker its artifical feel
system was much easier so they did so.

--
Mary Shafer               NASA Dryden Flight Research Center, Edwards, CA
SR-71 Flying Qualities Lead Engineer     Of course I don't speak for NASA
shafer@reseng.dfrc.nasa.gov                               DoD #362 KotFR
URL http://www.dfrc.nasa.gov/People/Shafer/mary.html
For personal messages, please use shafer@ursa-major.spdcc.com


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