Auto Tow Information

We found it better to use F250 than F150 - larger, more powerful, engine
and transmission give better acceleration, and we figured more likely to
be reliable if big engine not working too hard rather than small and
going at max output. The last ones we had, in 1988, were fine until we
had to stop autotow for other reasons. We went for "Super engine
cooling" which incorporates an extra oil cooler for the transmission -
launching involves high power at low road speed, and the transmission
oil needs all the help it can get.

The F250 spec we used in 1988 was:

F250 HD 4x2/133 w/base;

Omit radio;

Regular Cab Custom 7.5L V8;

Autotrans;

Super engine cooling;

Rr step bumper;

Spare wheel/tyre/carrier;

LPG conversion.

With a 4x2, it is important to have the tow hook at the back of the cab,
not at the back of the vehicle, so that the cable force does not lift
weight off the rear (driving) wheels. It is easier to get good tyre grip
with reverse pulley launching, where the cable pull is always horizontal
anyway.

You need a Tost or similar release to hook the cable on, to allow rapid
release in emergency.

A window in the roof is advisable.

There is a lot to take into account for reverse pulley launching.
Straight autotow is easier to equip and start operating. Even with that,
you need to follow others' lead in the cable/drogue/weak link/strop set
up and hardware, to avoid reinventing it by trial and error.

Chris N. (Essex, UK)

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At Enstone using parafil, we dispensed with a drogue chute for straight
autotow, to eliminate crosswind drift. XJ6 Jag with Tost release. We
swapped ends each launch to speed up launch rate. 60mph each way,
1500agl from 500m length. L-13 lifted the back of the Jag a couple of
times, so nice to have ballast in the back seat. Four-wheel disk
brakes also helpful at end of tarmac.

Personally feel the Cots reverse pulley system was most elegant and
effective of auto launch systems I've seen in 30 years, including the
Essex GC system.

A lot is made of the room required for ground launching. However, I
know it is quite feasible to establish a ground launch soaring
operation in many areas of the US by leasing, rather than purchasing,
space. Dry pasture and dry agricultural land can be leased cheaper per
acre than my club pays in property taxes, considering our improvements
and the tax basis. In many states, the federal set aside allowance is
greater than beef farmers can pay for grazing (leading to an
interesting observation by ranchers that they are competing against
their own tax dollars for the price of pasture land). Furthermore, a
startup ground launch operation is going to encounter far fewer NIMBY
objections than aero-towing over the local area.

You may find it's possible to winch cheaper than burning up someone's
$40,000+ F250 though, and winching doesn't require as much improved
land.

Frank Whiteley