Winch Experts wanted

Skylaunch already have developed, trouble-shot and
built 30 or so examples of the big V8 petrol/LPG twin
drum, controlled launch power winch design you seem
to be re-inventing. It sems sensible to use this experience
so why not just buy one, investigate building them
under licence, get a kit from them, or get Mike Grove's
advice on a consultancy basis?

As one of a sub-committee looking at the Supacat replacement
we have decided to recommend a Skylaunch to the Board
of Directors of our club as the only realistic option
available worldwide to improve on our current Supacat
diesel 180hp winch. The cost will be about £60,000
including options for the 8.2 litre LPG GM marine V8
version. The Supacat made a profit of £29,000 last
year and £16,000 in 2002 - after paying the cost of
full time professional winch drivers, maintence and
depreciation (from about 8-9000 launches I think).
The new winch will be paid off within a very few few
years. Busy, reliable, modern winches are just a license
to print money.

It is worth having a look at the Skylaunch german text
site as it has a whole lot more useful information
than the UK site about the various kit forms of the
Skylaunch and prices etc. It also has pictures of
the more basic Skylaunch 3 version.

http://www.skylaunch.de/

http://www.skylaunchuk.com/

John Galloway




At 22:18 23 March 2004, Ian Forbes wrote:
Now you are talking!

Lets get the fundamentals right. We want a design that
is easy to build,
not too expensive, simple to operate, easy to maintain
and with safety
standards to meet current best practice. Performance
should be capable
of launching a glass 2 seater trainer to a hight not
less than 1/3 of
the runway length in zero wind conditions.

I vote for a big block V8 petrol motor powering a double
drum winch. For
the guys who want to talk about exotics electric winches
and diesels
with modified ECU's - go for it but lets separate the
threads. I think
the successful 'one design' winch is going to run on
petrol and will be
made from readily available hardware. If we have any
spare cash left in
the budget we will spend it on plasma rope.

As a starting point, lets get some specs on winches
that have been built
already together with performances achieved. We need
to start off with
parameters like engine capacity and size, drum dimensions,
final drive
ratios, gearbox/torque converter details and the source
make and model
of the components used.

Then we need detail engineering drawings for the clever
bits. Winch drum
axle mods, guillotines, guide pulleys. These should
best be based on
proven designs. Details for a Skylaunch like throttle
control would be
nice. Good engineering detail for the safety items
like the operator's
cage and cable guards might save a few home builders
from unexpected
injury.

The engineering should accommodate a choice of cables.
Single strand,
multistrand or plasma. We need to spec those too.

We should also put together a 'bill of materials' for
anybody planning
on establishing a winching operation. I am thinking
of a comprehensive
list of things like weak links, rings, 'chute, snake,
signal lights,
radios, cable retrieve vehicle... That in itself would
at least allow
for drawing up a proper budget.

As for a forum - if we are going to move off RAS, Al's
gliderforum.com
might be a good home. If we want to run off an e-mail
list, I can
probably make a plan to host it. We will also need
a repository for
information - a web site - perhaps a 'wikki'.

Finally we need to establish some ground rules regarding
copyright and
ownership of the design. My vote is to follow the 'Open
Source' model
used by Linux etc. Publish everything and allow anybody
to use it - but
under the condition they publish details of what they
build and how
well it works.

Who's in?

Ian

John Galloway wrote:

Skylaunch already have developed, trouble-shot and
built 30 or so examples of the big V8 petrol/LPG twin
drum, controlled launch power winch design you seem
to be re-inventing. It sems sensible to use this experience
so why not just buy one, investigate building them
under licence, get a kit from them, or get Mike Grove's
advice on a consultancy basis?

The Skylaunch sounds like a great machine. However I have never seen
one. I fly in South Africa and there are none in this part of the
world. I doubt that there is a club in SA that could afford one.

I see from their web site that they will sell a guillotine for about
UKP2000. However you can buy a complete reconditioned crate V8 engine
for half that price.

The Supacat made a profit of £29,000 last
year and £16,000 in 2002

Our club launches mainly by aerotow. We winch once every two weeks.
However even if all of our training was by winch launch I estimate our
gross winch revenue would be about USD 10 000 per year - no where near
enough to buy a Skylaunch.

There must be must be a dozen clubs operating winches in this country.
Most of them have been home made, or home modified. Many man hours have
gone into building these machines. All work to a greater or lesser
extent but none are perfect.

If the next intrepid builder had access to the detailed plans of a
proven winch, it could halve his build time and avoid the inevitable
"fix up the problems" project which follows each "winch construction
project".

The end result may also just be a bit more efficient, easier to operate
and safer and that would mean more pilots flying gliders.

Come and join us at http://groups.yahoo.com/group/winchdesign/ we would
like to learn from your experiences with Supercat's and Skylaunches.

Ian