Glider - Towplane Signals

Training manuals and,in the USA, the FAA test, require knowledge of all
the in-air signals between a glider and towplane. In all my 25-years
of aerotows, I've only had four go bad (less than 1%). In one, the
towplane engine quit just after liftoff, but early enough to enable us
both to land on remaining runway ahead of us. I've had one spoiler
deployment, which I spotted and corrected as soon as I realized my ship
felt unresponsive and we weren't climbing! I've had two tows where the
towplane slowed to the point where I lost aerodynamic control and I had
to release to recover. In one of the latter, I was in low tow and even
a radio call couldn't speed the towplane up quickly enough. In the
second (and more recent) I was in a two-seater without a radio and
quickly sank from high tow to low tow, possibly out of sight of the
towplane pilot's mirror view. I didn't have enough control to wag
anything and my only recovery method was to release.

In all my four aerotow incidents neither pilot had time to signal the
other. I can see the need for towplane - glider signals (spoilers open
and release now) but how useful are signals from the glider to the
towplane? In particular, I really wonder if signals to
increase/decrease speed, while useful for winch or ground launch, are
actually useless in real aerotow situations?

I feel much more comfortable where both towplane and glider have
working radios (although I was one of the victims at a regional contest
when a glider on tow called "towplane slow down 5 knots" and all five
of them in the air did so simultaneously!)

And with all the emphasis on rope-break training, I've never had one!

Comments, anecdotes?

Mike ASW 20 WA