On 3/4/20 7:38 AM, Paul Remde wrote:

Any thoughts...? I'm just dreaming about the future of gliding...

Speaking as a winch instructor. One requirement for a safe winch launch
is for the glider to always be in a position to make a safe landing in
the event of a launch failure. Thus the launch profile must be such that
by the time that you are too high to land straight ahead you have
sufficient height to fly a small circuit and land back on the runway.
You also want some overlap between the two options to take the stress
out of decision making. If you winching into zero or low winds, a 180
deg turn and landing "downwind" is also an option.

If you are winch launching a sustainer, the requirement must be for the
glider to launch, release, attempt an engine start and then still be in
a position to make a safe landing if the engine fails.

What you do not want, is to make a habit of releasing over the downwind
threshold, to low to fly a circuit back over the runway. (Yes this is
accepted for aerotow. But the launch failure rate is much lower and
simulated launch failure training is done in light winds which allow
landing downwind.)

One option is a conventional ground launch, car or winch to say 1000'
AGL. Glider can then fly a circuit, start the engine on downwind and be
in a position to land if the engine does not start. This would work for
any sustainer technology. The ground launch is an "existing art" and you
can get training and ratings for it. There are also established clubs
with the means to provide the launch.

Next option is the "launch to 100'". This must be done such that you can
release, attempt an engine start and still be able to land straight
ahead if it fails. A variation involves deploying and even starting the
engine before launch, with a pylon mounted engine, like a jet, but not
possible with FES. This saves some time for the engine start and reduces
the risk of a start failure. These launches have been done, but you wont
easily find an "approved procedure" accepted by manufacturers and
authorities etc.

Last comment, is do not assume that FES cannot suffer a launch failure.
They have safety control systems and all it would take is one contact
breaker "trip" to spoil your day. Also remember that any battery energy
you use to get from 100' to "start of soaring" will not be available for
a retrieve later in the day.

But yes, this could be the future of gliding ...

Ian