Actually the Skylaunch comes as standard with a 3 speed changing automatic
GM TH400 gearbox. I drive Tost winches which have been retrofitted with
these gearboxes and I agree that the gear changes are not particularly
obvious to the winch driver, or to that matter to the pilot being
launched. With a sensible axle ratio the change from first to second
happens very soon after 'all out' and the change from second to top
during the ground run. If you listen carefully from outside the winch
during a launch you can hear them as a change in the engine note.

A changing gearbox gives a more rapid ground acceleration for heavier
gliders, and allows higher gearing in top for a greater range of cable
speeds without cooking the fluid in the torque converter getting the
glider moving.

Derek Copeland

At 18:56 14 July 2008, Tony Clark wrote:

I think you're wrong about the Skylaunch gear changes Derek! Our winch
has a torque converter, but I don't think it changes gear during the
launch! Or perhaps it does, but it's just that I have never been aware
of
it!



Tony Clark