On Fri, 15 Oct 2004 15:59:52 GMT, "Bill Daniels"
wrote:


"ruediger" wrote in message
. com...
Since 3 month I am proud owner of a H201B with 17m wingspan and
"Speizklappen". The glider I owned for 4 years, before i bought the
Libelle was a Astir CS77. I like the handling of the Libelle very
much, the only point I really have problems with, is that the Libelle
loves to drop a wing at the beginning of aero tow. Every take off that
a friend or me made with the glider was close to a aborted take-off.
Other Libelle Pilots said, I should try to open the air breaks for the
first 100m, but none of them owns a 17m version, which has extra
weight on the outer side of the wing because of the wingtip extension.

I am not used to this wing dropping by the ASTIR so I hope I can get
some additionell advice here.

It's an accepted fact that extending the spoilers or selecting negative flap
will enhance aileron control at low speeds. The magnitude of the effect
differs for various gliders so consultation with pilots experienced with a
particular glider is advised.

That said, there is another factor that may be involved.

I recall watching the grid depart at a regional contest where each glider in
turn dropped the upwind wing. There was about a 8 knot crosswind component.

After watching the show for a while I started to realize that the tugs prop
blast was drifting with the wind and striking the gliders down wind wing
causing it to rise violently. The onset of the effect occurred when the
glider had rolled about half the length of the tow rope or just after the
wing runner had released the wing tip.

When my turn came, I got ready to stuff in a lot of down wind aileron at
just the point where the glider encountered the tugs prop blast. It worked
nicely and I didn't drop a wing like those before me. Now I'm always ready
for the drifting prop blast.

Bill Daniels

In the commercial operation I used to run I saw this same wing drop
due to prop blast in the longer winged planes, specifically the Nimbus
2 and a ASW-22. I kept a 300 ft rope just for towing these guys. The
longer rope solved the problem.

You may wish to make up a 100 foot "weak link" to be used when towed,
(Assuming they are starting with a 200ft.) It would most likely
solve your problem.