Airspeed control during ground launch?

As I understand it.. the SSA and FAA manuals do not have it wrong.

A report from the recent Back in the Saddle safety seminar reveals that the
"more modern" winch machines now in Europe actually are more automatic,
maintaining a set tension on the line and varying the speed on the winch.
The reports are that the pitch control for speed control is then more in
tune with the standard practice of raise to slow (more tension, auto
throttle slows down) lower to speed up, less tension more throttle to speed
up the winch and maintain the desired tension.

If you are on an auto tow there is no tension meter or "take up reel" on
auto, so the Speed control would be as described in the SSA and FAA manuals.

BT


"Roger Worden" wrote in message
et...
What is the correct relationship between pitch angle and airspeed during
ground launch, either by auto or winch? Different sources make conflicting
statements:

1. Speed control is OPPOSITE to that during aerotow and gliding

* SSA Soaring Flight Manual, page 13-10: "Under most circumstances, the
best way to reduce the airspeed is to raise the nose. During ground
launch, however, the opposite is true ... pulling the nose up results in
an increase in airspeed, assuming the launch vehicle has adequate power."

* FAA Glider Flying Handbook, page 7-16: "The pitch attitude/airspeed
relationship during ground launch is unique. During the launch, pulling
back on the stick tends to increase airspeed, and pushing forward tends to
reduce airspeed. This is the opposite of the normal pitch/airspeed
relationship."

* This is what I was taught during autotow training. I can't say that I
have varied the pitch enough in my few launches to have demonstrated it.

2. Speed control is the SAME as during aerotow and gliding

* British Gliding Association Instructors' Manual, page 16-2: "If the
launch speed starts to tail-off, lower the nose." Page 16-3: "monitor the
airspeed trend. If it is falling back towards the minimum safe speed,
lower the nose or relax any back pressure on the stick." BGA does not
mention attempting to slow down: "If the glider is starting to go too
fast, maintain the normal climb attitude, and signal. If it remains too
fast, or gets even faster, release."

* During presentations on winch launch at a recent seminar, two leading
instructors discussed lowering the nose to increase speed and raising the
nose to decrease speed.

* This is what my experience with the Condor flight simulator winch launch
has shown.

It seems to me that this is a critical point on which to be clear, since I
will be winch-launching for the first time soon. I understand that the
vectors involved are different than in aerotowing, because the wings are
converting forward rope travel to angular motion (just like the skeg on a
water ski!). I also understand that a properly balanced glider using a CG
hook for winch launch will tend to nose up initially, and will seek an
optimal climb angle naturally. Altering the climb angle with elevator will
necessarily result in a less-than-optimal altitude gain. But what is the
actual effect of raising or lowering the nose in a stable ground launch
climb?

A. Is it different depending on the angle of climb? In my experience,
autotows tend to achieve a 25- to 30-degree climb angle, winch launch a
40- to 45-degree climb. Does that cause a difference in the effect of
pitch angle?

B. If #2 above is true, how did the SSA and FFA manuals get it wrong?

C. If #1 is true, is it reversed in Britain? (Just kidding...)