On Mar 12, 5:07*am, Mike the Strike wrote:
I believe this is related to the angle of incidence of the wing, which
requires the Discus to adopt a high nose-up attitude at slow speeds.
Under aero-tow, the rope pulls the nose down, which requires extra
lift from the tailplane. *At slow tow speeds, the tailplane cannot
develop enough lift to maintain the proper angle of attack of the wing
because of this pull from the rope.

Running out of elevator in such a situation does not imply that the
wing is anywhere near stalling.

I had a similar situation when I first flew a PW-5 behind a powerful
Pawnee tug. I was keeping the wheels of the tug on the horizon, and
it was horrid. I had almost no viz of the tug and the stick needed to
be waaay back.

After a while I realized that we were climbing so steeply that I
should be much lower. I was looking at the top of the fuselage! I
dropped down to where the tailplane was lined up with the wing and
things got much much better -- and the tug was *way* above the
horizon.