Winch launch clinic at Faribault, Minnesota
"John Scott" wrote in message
.. .
What type of winch was being used?
John Scott
It was an ex-Canadian Gerhlein style single drum winch with a Chevy 350 V8
and a GM TH400 series transmission. It's a well maintained example of a
1960's style winch. It's not ideal but cheap enough to get started with
winch launch. The ~1500' AGL launches it delivered were just fine for
contacting thermals. Had we not been in training mode, I could have
thermalled away on almost every launch.
The power was just right to allow the glider pilot to control airspeed with
pitch inputs but it did exhibit tension oscillations whenever the launch was
disturbed by a rough gear change or thermals as is typical with this type of
winch. We were able to reduce oscillations by using 2nd gear. 2nd gear
also eliminates the tendency for the TH400 to make a 3 - 2 downshift near
the top of the launch.
A modern tension controlled winch would probably increase the release
heights to 2000' AGL by holding rope tension nearly perfect.
Bill Daniels
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