On Monday, October 5, 2015 at 7:32:02 PM UTC-6, Sean Fidler wrote:
From the guy who ran the Cadilac auto-tow camp last year...

"Auto-tow pointers" - Cadillac, MI camp

Gliders: ASW12, ASK21, ASW15, RS15, and some others
Tow vehicle: Late model Ford Fairmont, V8, 305 cubic inch
Tow rope: Initially, dacron 1500 ft The next year spectra 1500ft
Runway length 5200 ft (field elevation - 800 msl)
Average altitude gain 1000 to 1200 ft (occasionally 1500ft)
Get away rate for cross country: 75%

Highlights:
Six pilots auto-tow launch endorsed in one day and a 12-year annual (Thank you Stan & Carol)
Over 100 hours of XC in the 12 from auto-tow in 1 yr

Lowlights: introduced to a club with many solo pilots, not many tow pilots, and left the unit with them for a year. They never used it!

Auto-Tow unit description: 1500 ft.rope on a reel powered by a Ford starter motor 1950's vintage (exposed shaft beyond motor housing) controlled by a dead man type switch. Reel in time about 1 minute. Easily fits in trunk. The emergency release mechanism is a larger copy of Schweizer tow release mounted to a hitch with a rope to the driver. The driver has radio communication to glider. The driver is any person that is willing. The driver is instructed to accelerate smoothly until glider lifts off and then add 5mph unless told otherwise. Normally, this meant (after glider lift off) full to the floorboard (and to remember that the runway does have an end!).

Note: the glider has a window that, if looked out of, shows the whole operation. So remind the driver as you see her, or him nearing the end.

For those of you that think this technique is not proper well, ok. For those that are willing, this is a way to launch sailplane with: 1) less cost and 2) no need for a tow pilot or tow aircraft. This auto-towing technique is ideal for any "club" with a willing group of two or more. Oh yes, the safety checks were performed on all gliders used. They all had properly functioning, carefully inspected tow releases.

sidenote - one fine lady got to boast that she jerked three guys off and kept them all up at the same time

Sean (still shaking my head at the sidenote).
7T

The former Enstone GC in the UK used autotow for several years. Parafil was used as it could be dragged along the tarmac without appreciable wear. Parafil is not pulley friendly (they tried). It was easily spliced.
Case study, http://linearcomposites.net/media/pa...e_study_13.pdf

The club moved on to winches before we wore out the parafil. 1500ft plus launches were done on a 500m length using an XJ-6 Jaguar with 275hp. We just pulled it back to the launch point at 65mph. Near tangled though we did snag a couple of things in the tall grass on the north side of the runway.

That engine replaced the 150hp Bedford diesel in one of the ex-ATC winches. Another winch was refitted with the motor and transmission from a stolen Rolls Royce that was burned on the airfield one night.

I don't think the third ex-ATC winch was ever put into service before the club folded.

Maybe some lurker knows the fate of those winches.

Frank Whiteley