On Dec 31 2010, 1:23*pm, bildan wrote:

I've flown some pretty heavy high performance gliders behind some
pretty bad tow pilots - one of them stalled the tug with me on tow.
If I'm careful not to over-control the ailerons, there's no problem at
all.

Heavily ballasted gliders respond sluggishly in roll just due to the
extra roll inertia. *A pilot trying to hold a precise position behind
a tug needs and expects crisp aileron response. *When he doesn't get
it, he increases the amount and frequency of aileron with a
corresponding increase in adverse yaw. *If he's less than equally
crisp with rudder to oppose the adverse yaw, it gets wobbly.

Bill, I use whatever aileron is required to establish and maintain the
bank angle I need. I also use exactly the right amount of rudder to
maintain coordinated flight. My low speed ballasted tows are not
"wobbly". I am momentarily out of control since the ailerons are on
the stops and I'm still not getting the roll response I need.

Please don't assume that the problem is caused by pilots not
understanding how to use the controls. The problem is caused by being
towed at a speed lower than that at which the glider is controllable
in rough air.

The solution is simple and entirely in the hands of the tow pilot.
The aerodynamic explanation is of little interest to me.

Your insistence on using the term "wobbly" to describe the problem
convinces me that you have never experienced it.

Andy