I had a two turn spin in my 20 a couple of years ago at a Mifflin
contest. The ship was in a coordinated right 45 degree bank, nose on
the horizon, and I was making my third searching circle attempting to
center the strong core of a good thermal. I was stable and coordinated
in the turn when the tail pitched up violently and the ship rolled
inverted to the right. My first thought was that I got hit by another
glider ... but since my searching couldn't locate another ship, I then
thought something broke. (It's amazing how time slows down in these
situations...) Entering the second rotation, I figured I was high
enough (4000')to jump, but continued to scan outside and inside and I
happened to look at my hand ... which was holding the stick just aft of
center. What, could this be a stall/spin? Opposite rudder, stick
forward, flaps to negative ... yep, recovery ... and immediately
climbing in the thermal again. I hit the tail dump switch and made a
promise to see if I could duplicate the situation when I got home ...
which I did.
Looking back, I suspect my left outside wing went through the tight
strong thermal core, which pushed the wing up, I instinctively applied
left aileron, and of course, the inside wing stalled, and the
combination of forces kinda 'snap-rolled' the ship to the right. The
spin entry from level flight and relatively violent forces disguised
the situation and delayed my recovery ... which of course is deadly at
lower altitude. So, stall/spins don't happen the way you practice them
.... although the recovery inputs taught are correct ... you just have
to execute immediately.
I now have a rule ... or mindset ... to execute stall/spin recovery
first in any situation like this. It won't help if you do indeed have
a structural or control problem ... but it is imperative avoid an
intellectual exercise if you are really in a stall/spin. As soon as
you hear yourself saying, "What the F___" ... you should be executing
stall/spin recovery.
KK
Papa3 wrote:
I agree that this is an interesting point. Even experienced, current
pilots
can be caught off guard, and perhaps a better training/recognition
method
might be in order. Maybe the yaw string can/should be a more
integral
part of the program in terms of spin recovery training?
For what it's worth, I have had a couple of unintentional spin
entries over
the last 20 years. One in particular sticks in my mind. A guy at
the
local gliderport is an experienced aerobatics competitor; he owns a
two
place Fox aerobatic glider. He asked me to go up with him one day,
since
he was having some trouble getting the Fox to climb. He figured
thermals
were a lot cheaper than 5,000 foot aerotows.
We got into a moderate thermal, and I took the controls to show him
how we
"real" soaring pilots thermal. I cranked us over to 40 degrees of
bank to
core the thermal. "Now, watch how I slow us up to really tighten
the
circle..." I said. The owner mentioned that I ought to "be a little
careful [since] stall speed at this..." He never finished the
sentence.
Departure was instantaneous. Rotation was spectacular. I recall at
first
doing everything wrong. It took me at least one full revolution to
realise
that the glider was spinning, and I think it was a couple of seconds
more
before I figured out the direction. Fortunately, we were at least
4,000
AGL at the time, and the owner just sat back and let me figure things
out.
This flight came on a day when I had been the duty instructor in the
club.
I had probably done 4 or 5 incipient spin lessons earlier in the day,
and I
probably had 40 hours flying in the preceeding 90 days. So, I was
current
and reasonably on top of my game.
This experience just reinforced the fact that the ability to
recognize a
spin, especially an unplanned one, is probably not an easy thing to
teach.
The normal training mode is thoroughly unnatural, as the student is
primed
and ready. The reality is a lot different, and I'm wondering if any
of us
emphasize the recognition aspects of the immediate post-departure
moments
enough?
Erik Mann (P3)
wrote in message
oups.com...
John,
interesting thoughts. Even with strong visual cues, the more nose
down
a spin, the more difficult it might be to surmise its direction.
Thus,
a quick reference to the yaw string is in order. Isn't the Pooch
known
for its nose down attitude while spinning?
Yet another reason to put the emphasis on stall avoidance and
prompt
recovery from prestall conditions. A suprise stall and autorotation
at
low altitude presents a great a risk, even for well trained,
heads-up
pilots.
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