In Europe we now have EASA to protect us from ourselves. I am sure there is
already, or will be very soon, an EASA edict to say that we cannot launch
anything behind a car without 12 hours of training of both driver and
pilot, a written exam on the maths involved, a practical test (with annual
renewal), and a fee to pay too.

This is a shame. Many years ago a venerable pilot at my club was told by
the CFI that it was much too windy for him to fly his K6 on the local ridge
and was refused a launch.

So he hitched his trailer up to his Ford Cortina and drove to a field at
the top of the ridge. He rigged and his mate then towed him with said
Cortina towards the ridge using a standard aerotow rope. This was so
successful he did it again the next day. This sort of derring-do was what
gliding was made of then.

Unfortunately in EASA land gliding is becoming a paperwork exercise and is
getting boring. You do not know how lucky you are in the land of the free
that you are still allowed to put yourself in danger.

Jim


At 00:28 19 October 2011, Martin Gregorie wrote:
On Tue, 18 Oct 2011 06:28:45 -0700, Andy wrote:


As I said in my first answer "if the climb profile was flown
correctly".
Auto tow does not require an aggressive climb profile to reach maximum
altitude as long as the runway length is not limiting. Unlike winch
launching the rope length remains constant.

To me, auto-launching on a 200 ft rope sounds uncomfortably like aero-
towing on a CG hook except that now you're *trying* to get above the
'tug'. This sounds to me like a recipe for getting into the
uncontrollable sling-shot region that upsets tugs. Further, it seems to
me that if you do that to a rear-wheel drive vehicle your problems will
be compounded by a loss of acceleration due to loss of traction as the
rope tension reduces the weight on the driving wheels.


--
martin@ | Martin Gregorie
gregorie. | Essex, UK
org |