All this talk about propellors reversing.
I fly a fairly high
performance modelflying wing glider I slope with. When it is
soarable it is very hard to land because when you dive you gain tremendous
speed.
I fitted a small electric motor with a folding
prop and a car speed controller that is reversable.
On a
flying wing almost anything you do to drag things up changes pitch, that
is except putting motor into reverse. Boy does that drag things up.
A nagging question I have had with flying with a reversable prop
was would it not be prudent to go up to altitude and fool with putting it
into reverse and also very fine flat pitch to recognize reaction of
aeroplane, and if it were to occur uncommanded, turn off motor which would
turn you into a reasonable glider instead of a lead sled?
My
DAR was test flying a RV, and throttle stuck at 1600 RPM on crosswind, he
ate up half the runway when it became apparent had he shut off motor right
away, landing would have been uneventful instead of crash.
Just
another story, I was talking with a high time instructor who was giving a
student last flight before IFR checkride. Motor at a few hundred feet with
plenty of runway ahead, but plane stalled and spun in? Ended up crank
broke right behind main bearing and prop began to freewheel. He said he
was pointing down much steepier than normal but plane stalled because of
horendous drag created by big disc up front.
For those who have
not first hand experiance, next time you get hold of a pinwheel, hold it
out car window at 30mph with pinwheel held captive. Not too much drag. Let
it spin up--- WOW an amazing amount of drag. Prop going into reverse is
not much worst than freewheeling prop BTW
Ron
Parigoris
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