Winch Experts wanted

Dave,

there are several of these hydrostatic winches around, one of them at
my old club in Germany - see the Skylaunch album under K,
Kamp-Lintfort.
This winch is a technical marvel but also very expensive to maintain
(Fluid, filters, HP-Hose, etc.) Another one was built in cooperation
with Danfos, I believe. I think this is a very complex design, too
complex for a group of amateurs to build.

Ulrich Neumann


Dave Martin wrote in message ...
Unless a mass batteries are used, the logistic of supplying
power to several possible winch stations around and
airfield to provide a days winching seems very expensive,
although a 'plug in and play' system would be an ideal
way of operating.

Has anyone considered the use of 'Hydrostatic Pumps'

Using the main engine to drive a hydraulic compressing
pump, as used on mechanical diggers etc, a hydrostatic
pump on each individual drum would provide the power
to launch the glider.

It would remove the need for complex mechanics and
by a simple system of taps could drive any one of a
number of individual drums.

Using deep sided drums without pay on gear would reduce
build costs and time.

Building the winch on a trailer would be simple, mobile
and may be cheaper than using complex mechanical drives.
It would also be simple to maintain. I understand modern
pumps can be programmed and controlled electronically.


The main pumps can provide sufficient power as can
be seen on mechanical diggers, but they are only pumping
us a telescopic ram. I believe they are used on slow
moving agricultural equipment to provide drive to the
main wheels.

The question is could the pumps provide the power and
speed to drive a drum for several minutes to enable
a glider to be launched.

Similar pumps can be seen at

http://www.casappa.com/

Although I am sure they will be available throughout
the world.


Dave

"Jim Vincent" wrote in message
...
In my experience, one drum is pretty adequate.

Most fields in the US are limited in length, so the launch height is
usually
just enough for a pattern. I find with one drum I can launch a ship,
retrieve
the chute, and have be back at the launch point just as the glider lands.
We
turn the glider around (usually lands cross wind), and we're ready to go
with
another. We achieve about 6-7 launches per hour this way at my
field..until
two or three other people turn up (with little experience but they're
BS'ed the
membership into thinking they know what they're doing) and our rate goes
down
to about 3 an hour.

Jim Vincent
CFIG
N483SZ
illspam

Jim, with one glider, one drum works fine. The length of the field doesn't
matter since with a longer field, the glider goes higher and stays up longer
so the wire is still back at the launch site in time for the glider landing
if the retrieve driver hustles. If you are launching from grass, all those
wire retrieves are sure tearing up the turf.

My most recent winching is with 5000 feet of wire and 2000 feet AGL is a
common release height. If there are any thermals, the glider will contact
one 3 out of 4 launches and soar away. In the western US there are many
runways 7000 feet or longer where winching is possible. You're talking
3000' AGL launches with that much room.

With a gaggle of gliders waiting to be launched you need the efficiency of
multiple drums or multiple winches. The real issue is often not how many
launches you can make in a day, it's how fast can you get everybody launched
when the thermals start. I've read of several winch operations that achieve
a sustained launch rate of one every two minutes.

Bill Daniels

I second the yahoo groups.

Frank Whiteley

"Mark Zivley" wrote in message
news
We all know "cheap" is a relative word. Cheaper than a Skylaunch leaves
a lot of ground. Just like any design project, we need to start with
some goals.

Reality is that a 2 drum winch probably is the peak in operational
efficiency coupled with simplicity of design. Piggot's book recommends
multiple 2 drum winches over winch designs with more than 3 drums.
Safety for the operator is paramount and clearly we need to be providing
enough power to handle a glider on a Black weak link. In general this
design should keep cost in mind, but surely as any club or group starts
to embark on construction they will have a lot of latitude as to how
they control costs. Do they buy a crate motor for $3-4k or buy that
little old lady's Cadillac for $500.

However, the first thing needs to be a forum off of RAS where we can
work. Ulrich started this, so I'll defer to his preferences. The Yahoo
groups are free, offer file sharing (I think) and it's easy to set up
topics to be voted on by the members. With that, we can start nailing
down the design goals.

Bill Daniels wrote:
"Ian Forbes" wrote in message
...

Mark Zivley wrote:


This project should probably be moved to a slightly different forum
like a yahoo group where people interested in participating can do so
without
filling up RAS. This also allows the sharing of files and even voting
on ideas as the project starts to take shape. We're definitely onto
something here, lets get started. We should start by doing some
deciding as to what will be designed. 1 or 2 or more drums.....

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



Ian. I admire your enthusiasm and support your ideas, but the economics
need
a bit of discussion.

Winches are VERY profitable. The operational cost is less than $2US per
launch and most people will find $10 is a reasonable launch fee. That's
a
500% profit with a volunteer crew in a club setting. The Return On
Investment for a $30,000 winch is just 63 operating days figuring an
average
of 60 launches a day. A dual drum winch in a training environment can
do a
LOT more than 60 launches a day.

After the club has its ROI it can buy a new glider every year with the
profits. That's the REAL secret of how those European clubs own all
that
nice glass. They put their money into gliders instead of air tow fees.

My concern is that by focusing on the "build it cheap" aspect, the
productivity of the machine will be lost. That's where American winches
have gone wrong in the past. Just a couple of weekends lost to winch
repairs is significant. If the "Hassle Factor" is too large, people
will go
back to air tow.

Build it right, make it reliable and as productive as possible no matter
if
it costs more to build. If a diesel engine is more productive than a
spark
ignition engine then pay the extra money for one. If Spectra improves
the
operation by reducing cable breaks and tangles then pony up for it. The
ROI
comes very quickly. Almost ANYTHING that increases the number of
launches
per day or makes the whole operation easier and more pleasant is worth
the
investment.

Bill Daniels

"Dave Martin" wrote in message
...
Some years ago when our Ford V8 and straight Jaguar
engines were falling apart someone suggested we went
on to Chevrolet engines 5.7l.

These were originally sourced from ex US Airforce buses,
like the typical US school bus. We bought the bus
took the engine out then scrapped the remains of the
bus. They were cheap even with a bus attached!

As far as I can recall they engines went straight in
the winch and then as they got tired were given a 'stock
car' tune and with heavy duty pistons etc.

Over about 15 years the engines have given excellent
service.The automatic gear box that came with the engine
is used for the drive and the drive lever fixed so
the winch driver can only engage neutral or drive.
The drive to the prop shaft can be tailored to any
axle with a bit of skilled welding.

Our main winches are a Skylaunch and Tost with the
Chevrolet engine. The engine in the Tost sits on a
sledge with gearbox and radiator attached, so if anything
breaks it can be easily removed and a spare slid in.
The current engine runs on gas and will launch A DG
500 with no problems.

We went for this engine because it is readily available,
either new, from a bus or re conditioned. Spare parts
are also available. It can also be easily tuned and
played with to produce extra power

Not sure what the full description of the engine is
but this US site found by a simple internet search

http://www.automotix.com/engines_by_...-engines_t---C
HV-350RLB-4.html

This looks like the engines we use. The prices also
look very reasonable.

Dave

Great engine, but barely adequate at 5500MSL with normal aspiration.

Frank Whiteley

"Bill Daniels" wrote in message ...
"Ian Forbes" wrote in message
...
Mark Zivley wrote:


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


Ian. I admire your enthusiasm and support your ideas, but the economics need
a bit of discussion.

Winches are VERY profitable. The operational cost is less than $2US per
launch and most people will find $10 is a reasonable launch fee. That's a
500% profit with a volunteer crew in a club setting. The Return On
Investment for a $30,000 winch is just 63 operating days figuring an average
of 60 launches a day. A dual drum winch in a training environment can do a
LOT more than 60 launches a day.

Yes, Yes, winches are profitable. That's a huge thing for any club to
consider. Our winch will continue to revive our club. Without it we would
be dead. You can make a go with as few as 15 or 20 members because
flying produces revenue as opposed to breaking even or losing revenue
and relying on dues for income.

After the club has its ROI it can buy a new glider every year with the
profits. That's the REAL secret of how those European clubs own all that
nice glass. They put their money into gliders instead of air tow fees.

My concern is that by focusing on the "build it cheap" aspect, the
productivity of the machine will be lost. That's where American winches
have gone wrong in the past. Just a couple of weekends lost to winch
repairs is significant. If the "Hassle Factor" is too large, people will go
back to air tow.

After running one of those cobbled up underpowered wire eating monsters
for a season I fully understand why poeple in the US have been turned off
on winching. Way to many winches have been built with the "kics" method.
Read carefully that's "kics" (keep it cheap stupid).

Build it right, make it reliable and as productive as possible no matter if
it costs more to build. If a diesel engine is more productive than a spark
ignition engine then pay the extra money for one. If Spectra improves the
operation by reducing cable breaks and tangles then pony up for it. The ROI
comes very quickly. Almost ANYTHING that increases the number of launches
per day or makes the whole operation easier and more pleasant is worth the
investment.

Bill Daniels

I think that there seems to be an understanding that the winches are
for the most part rusting down in the US because they were poorly designed
and the group is now looking for a good dependable design. Fortunatly I've seen
little emphesis placed on being cheap in this thread. FYI the PSA winch
see www.permiansoaring.us has all new or professionaly rebuilt everything,
single drum, plasma rope, and could be duplicated for around $14,000.00 by
amatuers utilizing fabricators to build drums and wire guides which were
the only parts requiring machine work other than the engine rebuild which
was also farmed out to a local engine rebuilder. This was at one time in the
recent past considered a large amount to spend. Good news is, it's really
a good winch. Add a few more good ideas and refinements and you could have a
easily duplicated two drum winch for less than $25,000.00 and it would
really perform. I think that this would be a good starting point. In the
future as winching becomes more popular that $25,000.00 may seem like
chump change, but for now it's enough to build a winch that will provide
years of safe dependable launches. OK I'm in.

Craig-

F.L. Whiteley wrote:
I second the yahoo groups.

I've created a new Yahoo group "Winch Design" in the "Soaring" category.
To subscribe send an email to ,
or visit the group page at:

http://groups.yahoo.com/group/winchdesign/

I am the list owner, I'll limit my moderation activities to making sure
that new members are, in fact, glider pilots or other interested
parties. Otherwise, have at it...

Marc

At 04:48 24 March 2004, Bill Daniels wrote:

Jim, with one glider, one drum works fine. The length
of the field doesn't
matter since with a longer field, the glider goes higher
and stays up longer
so the wire is still back at the launch site in time
for the glider landing
if the retrieve driver hustles. If you are launching
from grass, all those
wire retrieves are sure tearing up the turf.

My most recent winching is with 5000 feet of wire and
2000 feet AGL is a
common release height. If there are any thermals,
the glider will contact
one 3 out of 4 launches and soar away. In the western
US there are many
runways 7000 feet or longer where winching is possible.
You're talking
3000' AGL launches with that much room.

With a gaggle of gliders waiting to be launched you
need the efficiency of
multiple drums or multiple winches. The real issue
is often not how many
launches you can make in a day, it's how fast can you
get everybody launched
when the thermals start. I've read of several winch
operations that achieve
a sustained launch rate of one every two minutes.

Bill Daniels

Bill

Flying from a grass/winch site, the wire does little
damage to the grass, the biggest problem is the cable
retrieve vehicle creating tracks.

We use a Landrover with low pressure tyres.

I agree with the last paragraph on efficiency and launching
a gaggle of gliders when the soaing starts, but what
is also require is an efficient method of delivering
the cables to the launch point. If the winch driver
does it then you have to wait for him to return to
the winch. The longer the airfied the longer the wait.

If the lanch crew are switched on then by the time
the retrieve driver gets back to the winch, the cables
should have been used.

This ties up one man for as long as there are gliders
waiting to be launched it is as big a factor as having
a good winch and driver. Maybe one reason why clubs
prefer aerotowing, it requires less man power.

The retrieve vehicle driver always wants to stop at
the launch point and chat rather than return to the
winch end to wait.

The Long Mynd use a retrieve winch which with a good
crew is very efficient and can work with a single drum
winch.

Efficiencey rates vary but with a switched on crew
periods one launch every 4-5 minutes can be sustained
for several hours average. This can be speed up slightly
and some UK will claim better that this, but for normal
club operations a higher rate is rarely required.

Still better than one tug where the tow to 2000 feet
takes about 7 minutes.

Dave

"Dave Martin" wrote in message
news:c3rjqe$2bh8m7
The Long Mynd use a retrieve winch which with a good
crew is very efficient and can work with a single drum
winch.

Dave



A visit to Long Mynd is on my "must do" list.

It has been my impression that while a retrieve winch works well when
launching from a ridge top where the height gained in the winch launch is
unimportant, lifting the retrieve wire is a hindrance when launching from
flatland where every foot of release height is very important.

What I don't know is how much hindrance. Do you think a retrieve winch
would be a good idea with 6000 feet of winch cable? If so, what is the
longest wire where a retrieve winch is practical?

Bill Daniels

On Tue, 23 Mar 2004 16:42:31 -0700, "Bill Daniels"
wrote:


Winches are VERY profitable. The operational cost is less than $2US per
launch and most people will find $10 is a reasonable launch fee. That's a
500% profit with a volunteer crew in a club setting. The Return On
Investment for a $30,000 winch is just 63 operating days figuring an average
of 60 launches a day. A dual drum winch in a training environment can do a
LOT more than 60 launches a day.

After the club has its ROI it can buy a new glider every year with the
profits. That's the REAL secret of how those European clubs own all that
nice glass. They put their money into gliders instead of air tow fees.

Just one question, Bill:
Why do you set the price for a winch launch that high?

In all the (European) clubs I know of a winch launch costs between $0
and $5 (less for student pilots, I'd estimate the average is $2.50),
making the flying itself very cheap. Income from winch launching is
certainly not the factor why European clubs own all that nice glass.


Isn't the cost for the launch THE major factor of gliding's total cost
and needs to be kept as low as possible in order to attract new
members (and keep them)?




Bye
Andreas

Andreas Maurer wrote:

In all the (European) clubs I know of a winch launch costs between $0
and $5 (less for student pilots, I'd estimate the average is $2.50),
making the flying itself very cheap. Income from winch launching is
certainly not the factor why European clubs own all that nice glass.


Isn't the cost for the launch THE major factor of gliding's total cost
and needs to be kept as low as possible in order to attract new
members (and keep them)?


Well i have just checked the tarifs at Bunno-Bonnevaux, and i can see
that a complete membership (including unlimited number of flying hours)
is about 1700 euros per year. This is of course a very good club,
equipped with fine glass gliders, and which uses paid employees, so
providing a hassle free solution. Also the soaring conditions are
generally good, and the distance to Paris is reasonable. I suppose that
the other large clubs of the Paris region (Beynes, Chartres, etc.) have
similar conditions.
Unfortunately they don't have a winch, hence you must add to that the
cost of aerotows, but this has always been for me a much smaller
expense. Using winches will reduce costs for sure, but this will be a
marginal reduction. I am still convinced that the cost of gliders is
number one factor for the sport problems.





Bye
Andreas

--

Michel TALON