Yes, we have those signs: show your palm on the left side of the
towplane by facing your palm to the wind (if the cockpit is closed than
we use the same method what you described). This is what was used in
this case but there was no response from the glider pilot.

/Janos


John Giddy wrote:


Don't you guys have a simple visual signalling system
between the tug and the glider ?
In a situation like that, our tuggies waggle the rudder
enough to make the tug yaw back and forth. Signal means:
"Too much drag. Fix it !"
Waggle wings means "Get off NOW. Tug in trouble"
Cheers, John G. (Australia)