On Oct 31, 3:40 am, Chris Reed wrote:
Andy wrote:
On Oct 30, 12:42 pm, wrote:
On Oct 30, 1:49 am, "Bert Willing" bw_no_spam_ple...@tango- On this (aborted) launch, I was still rolling, both wheels on the
ground. I noted the chute opening in front of other gliders too,
while on the ground. I'd had no problems launching with our non-
chuted poly rope.

How springy is 3000 feet of spectra? I imagine that would be more of
a factor for auto tow than winch. I'm speculating that the problem
with the spectra launch is not the parachute itself but the dynamics
of the rope tension. The result may be strongly dependant on how the
tow vehicle accelerarates to nominal launch speed.

Andy

That makes senses. My guess would be that the tow vehicle changed gear
and thus briefly reduced power, which would probably be enough to allow
the chute to start to open. Some automatic gearboxes have quite a
deliberate gear change, enough to reduce the tension on the rope. If
there's a lot of spring in the rope a gear change could set up some
brief oscillation, enough to allow the chute to flap around.

Did it close again, or remain open? If the latter, either the tow
vehicle wasn't pulling or there's something very odd about the chute design.

The chute stayed open. (at least until I was too sideways to see it!)