New 29 Palms Winchfest Video

Bill Daniels wrote:
"Martin Gregorie" wrote:
I tried it enough times when I was pre-solo, thanks, in both ASK-21 and
Puchacz. Didn't work with them. The only effect I remember it having was
breaking a weak link with the Puchacz in a gust.

I did experience a small speed drop today, also in the Puchacz as it
happens, but from the rate and amount of the decrease that was the driver
adjusting the power by making a small reduction at around 500 ft. After
that the remainder of the launch was smack on Vwinch (59 kts) until he
chopped power at the top and we floated off at 55 kts.

We have two Supacats. One has a 240 hp Deutz aircooled diesel V8
industrial engine and the second a big diesel straight six, probably
around 180 hp: I think we were using the straight six winch today. Both
winches drive the drums with a custom gearbox, in turn driven through a
fluid clutch. There are no gear changes during a launch. AFAIK the gearbox
does the following:
- reduction gear. Drum speed is less than engine RPM (of course)
- drum selection (its a two drum winch)
- oscillating drive for the pay-on system


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

Keep trying it. I think you will find you have control over airspeed.
180 - 240 HP isn't nearly enough power to prevent a big 2-seat glider from
slowing the winch.

I assume Martin flies at the Cambridge Gliding Centre. Their V8 Supacat
could not be slowed by pulling (and in fact sped up at times) through
multiple attempts by myself and an instructor (both of us in the 200+ lb
range) in one of their ASK-21s. The only otherwise unusual outcome was
a premature back release late in one launch. This was done with prior
knowledge and discussion of the fact that it should theoretically be
possible. I'd guess there is no overcoming gobs of torque...

Marc