Winch Launch Fatality
On Jun 24, 4:38*pm, Andreas Maurer wrote:
On Wed, 24 Jun 2009 08:29:22 -0700 (PDT), bildan
wrote:
It's realistic in the sense that the most likely way a wing would go
down is if the pilot does, in fact, "stuff it down". *Unfortunately,
you just have to watch a few takeoffs to see it happen. *One of my
frustrations is pilots who seem to have no idea where their ailerons
are until a wingtip hits the ground.
If the pilot consciously centers the ailerons as part of the pre-
takeoff checks and lets the wing runner balance the glider, the glider
will just stay balanced on its own for several seconds after the wing
runner lets go *- long enough to get aileron control on either aero
tow or winch. *That's good practice with any launch method.
Hi Bill,
I'm not sure if your observation is correct.
During aerotows you often see the wing runner working hard to keep the
wing perfectly balanced, the pilot keeps ailerons centered, wing
runner lets go - and the wing tip hits the ground immediately before
the pilot has time to apply aileron. A typical crosswind situation.
The problem is that the pilot cannot sense the wing-drop tendency (and
apply opposite aileron) as long as the wing runner keeps the wing
level.
The better technique is if the wing runner follows the wing-drop
tendency, not trying to keep the wings level - the pilot is going to
feel one wing going down (although still held by the wing runner,
hence no danger of the wing tip touching the ground) and will apply
aileron immediately. This usually works like a charm.
And then there were those open class ships in crosswind situations
where you have to apply full aileron to the lee side from the
beginning of the aerotow (even if this wing drops)... because despite
full aileron this side it's going to come up again.....
If the wing runner balances the glider into the crosswind while the
pilot holds neutral aileron it will work just fine, but the two have
to work together. The wing runner should feel for the tilt into the
wind that balances the glider so it's a tossup which wing would fall
if he let go but he can only do this if the ailerons are neutral.
Another instructor and I worked this out long ago. Since we often ran
wings for each other it was easy to teach the technique to our
students. (Ailerons neutral until the wing runner lets go - then fly
the glider with the same bank into the wind as the wing runner gave
you.)
If the wing runner just "holds the wing level" it may well drop to the
ground when he lets go. If the pilot is wagging the ailerons around,
the wing runner can't do anything to help.
BTW, there's another 'gotcha' you often see with aero tow takeoffs in
crosswinds. A crosswind will blow the tugs propeller blast downwind
so it hits the gliders downwind wing. The glider encounters the prop
blast after rolling about half the towrope length. Usually by then
the pilot is holding into-the-wind aileron which together with the
prop blast will slam the upwind wing into the ground before the pilot
reacts. If you are ready for it, you can handle it OK but it catches
many pilots unaware.
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