You can't just control for constant force. You also need to limit the
maximum winch speed to address this exact issue.

Mike Schumann

"alex8735" wrote in message
oups.com...
I personally don't think that a constant force regulation results in an
ideal winch tows. I have observed a number of tows in which the glider
was initially accelerated to quickly so that the pilot reacted by
maintaining a low climb angle. This low angle results in lower force
measured by the winch and leads to a further increase of power. In a
Ka8 nearing Vne the only possible action is to abort the tow.

At our airfield we use a system which transmits the airspeed of the
glider to the winch operator. Pared with a good winch operator and a
powerful winch, this results in very good winch tows.