Safety of winch launch vrs. aero tow?

Bill Daniels writes:

If you don't like the way a winch launch is going, release and land. You
can do that with a winch launch because you should always be in a position
to land back on the runway - I can't say that is always true with air tow.

This brings up a point I left out of my original post. The SITE must be
suitable for winch launching. If the site has a short runway, or obstructions,
then the option to release and land straight ahead may be limited. Of course
this applies to aerotow as well.

Winch launch accelerates the glider far faster than air tow so dropping a
wing due to insufficient aileron control is unlikely. (Of course, you can
still drop a wing due to incompetence with unhappy results.)

If the winch operator does not apply adequate power for rotation and climb
early in the launch, the window of opportunity to abort safely closes quickly
and leaves unsuitable options.

In both cases, the training of the pilots and launch crews have a lot to due
with overall safety. There is ample opportunity for either to come to a bad
end. With equally good training, I think winch launch is safer.

I wholeheartedly agree that training, and practice, are of great importance. I
had a winch launch accident early this year in which training played a large
part. Also reaction time, and the limited suitability of the site for winch
launching.
I will give a brief description of the accident:
I did not brief the winch driver on my launch requirements (mistake 1), my
glider had the highest wingloading of any there that day.
The initial acceleration from a stop was weak enough in comparison to all my
previous training on this winch to make the hair on the back of my neck stand
up. I had enough room to wait for more power (mistake 2) but was too low and
slow to wag wings. I briefly pulled back on the stick to see if there was any
tension on the cable, maybe the winch had redlined in a lower gear (the winch
in question has known issues, mistake 3). I felt the tension completely go
away, pulled the release and pushed the nose over. I was not aggressive with
the push over (mistake 4), but altitude was only 50-75 feet and the glider was
just above stall, so not enough room to gain speed, no room to land straight
ahead, and insufficient altitude to complete a turn to the right for a landing
on the abort runway.
I dragged the right wing and ground looped, breaking the tail boom of my
glider, and narrowly missed a Toyota truck that was parked in an unsafe area.
During debrief, I found out that the winch driver saw the retrieve chute
balloon immediately and thought I released so chopped the winch power. Chute
blossoming was common that day on previous launches due to improper chute
rigging (mistake 5) and this was probably exaggerated by the lack of full power
during the initial part of the launch. The site has about 1000 feet of usable
straight ahead runway, but it is downhill from glider to winch, and a portion
is steep enough so as to be impossible to walk uphill if the dirt is wet. The
abort runway is at a right angle to the launch runway, undulates in elevation
30-40 feet, and has a narrow spot about 60 feet wide bordered by trees and
bushes.
The dimensions of the site are such that there is a point in the launch when
you may be too high to land straight ahead, too low to continue into the ridge
lift, and too low to make the landable portion of the abort runway. The
situation is worse for higher wingloading gliders (I fly an ASW20) than are
typically flown at this site. Some of you may have guessed the site by now, it
is Torrey Pines, California. Having had this experience, I would fly there
again, but only after addressing the training and briefing issues mentioned.
The configuration of this site requires extra special attention to launch
procedures, but the satisfaction of flying at such a unique and historic
location is well worth it.


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Mark Navarre
ASW-20 OD
California, USA
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