Duo Turbo Climb / Altitude performance

wrote in
ups.com:

Without checking all the data (aren't loggers cool ?) it feels like the
DG500M gets better climb performance on its own then when behind the
180HP Super Cup but not as good as the 235HP Pawnee. It also feels
that weight makes more of a difference then DA. I have never self
launched my DG below Boulder's field elev nor fly in cooler weather so
can't really comment on the other side of the spectrum. Though I read
(maybe on the Aux Sailplane Assc news group or the DG owner site) that
the flapped ships do much better. It is interesting that DG had
problems certifying the new non-flapped DG-1000 as a self launcher and
for now its only available as a "turbo" like the Duo Discus. I follow
the manual and climb at flaps +10degrees at Vy 49kts.

Graham Beasley DG-500M Hotel Golf
home.comcast.net/~grahambeasley/dg4sale


Years ago we had a DG-500M at Soar Truckee. On high density altitude days
his self launch climb rate was dangerously low. The glider was also heavy
enough that the Cessna 182 tow planes that we had at that time gave a
dangerously low climb rate. His solution was to aerotow with the engine
running. Takeoff roll was shorter, initial climb rate was much better, and
rope break options were much better. He was able to release at 1000' AGL
or lower to go find a thermal.

IIRC he had to use reduced throttle on tow to prevent engine overspeed at
typical towing speeds.

My only worries about this method are the chance of slack line or broken
rope tangling in the prop, and the extra drag if the glider engine quits
early in the launch.

Does anyone else out there have much experience with this "towplane plus
self launch engine" method?
-Bob Korves