Soaring Safety

One thing I've wondered is whether some of these "wing lift" incidents
are actually *wing drop* incidents. I don't have much ridge-time in
full-scale gliders, but I have already experienced some good amounts
of turbulence.

There's nothing that says a turbulent parcel of air couldn't hit the
wing that's closer to the ridge. After all, the wing closer to the
ridge is also closer to the ground. Accordingly, that wing is
possibly more exposed to turbulence caused by ground features - these
can extend downwind (i.e. up-slope) to a distance of 10 or 20 times
the height of the original object. For example, a 100-foot-tall tree
can create turbulence over 1000 feet downwind of it. When I did slope-
soaring with R/C gliders, we used to have to be VERY cautious of this
- so its always in my mind when I visually scan the ridge ahead of me
when in my cockpit.

So imagine a situation where you're getting rocked by lift and
turbulence, and all of a sudden the ridge-facing wing drops. Could
you confidently distinguish that from a wing-lift on the opposite side
if you're going through pulses of lift and sink, or turbulent roiling
air?

Of course, there's a BIG difference in what might be the best way to
recover from those two different situations. With a wing-drop, you
have a stalled condition - giving the aircraft full aileron to lower
the upwind wing just increases the angle of attack on the stalled wing
and doesn't make the situation any better. And if we're close to
terrain we might subconsciously be pulling on the stick, too (again,
not helpful to a stalled wing).

....Just some food for thought that a relative newbie like me wonders
about at midnight (being a night-owl I tend to be obsessing over
gliders at that time quite frequently *grin*).

Take care,

--Noel