Tony Verhulst wrote:
Bill Daniels wrote:

No winch? Buy or build one.


In the northeast US we have lots of trees and our airport is a
relatively narrow rectangular plot of cleared land surrounded by trees -
lots of trees. In any kind of cross wind, where would the winch rope
land after release? Right!

The glider grass runway is next to the paved runway used by the power
crowd. A paved taxiway leading from the paved rwy to the ramp crosses
the grass runway at midfield. The airport manager would, properly, be
not inclined to permit winch launching across an active taxiway.

There are lots of cases where a winch is not an option.

Tony V.

Our experience agrees with regulation. You need 30m (roughly 170 feet) between
the winch cable and the trees, and the winch cable and the runway. If you
measure you will probably find you do have enough space.

As for the cable landing in the trees, this depends on your design. We have a
huge open field, and a winch that is a bit slow on pickup/prone to looping. For
this situation we use a fighter (Dassault Mirage F1 FWIW) drag chute. This is
choked till it gives us a quick opening chute with a stable slow descent. When
you apply power, it comes down nice and controlled and keeps the cable under
tension, but in strong crosswinds it can have the cable only just clearing our
boundary fence about 250m away.

The general design is for a much smaller, heavier chute (700-800mm) that falls
much faster - and keeps the cable closer to where it was dropped. This of course
is the crux of the matter. A winch pilot who knows what he/she is doing will
launch upwind in a crosswind so that the cable falls toward the centreline. The
small chutes are made of a tough canvas and when they do land in bushes etc. the
general practice is to simply drag them free - making sure the area is clear and
it is safe to do so of course.

We simply do not launch if the crosswind component is too strong for safety. In
our case that is well before cable drift is a major problem.