Safety of winch launch vrs. aero tow?

"E. A. Grens" wrote in message
...
JJ -

I, as a power pilot, learned to fly sailplanes on the winch, overseas. I
now only fly aerotow, and am not signed off for ground launch. One thing
I
have not seen mentioned is the qualification of winch operators. Tow
plane
pilots ( I'm not one) have to meet certain standards and be signed off. I
became a winch operator by volunteering out of club spirit (stupidty?). I
was informally instructed by a winch operator who desparately wanted to
escape the exile of the winch. Then I was left to do the job, getting my
flights at the end of the day. They brought me food and drink
(nonalcholic), but no one "qualified" on the winch would come near for
hours. I'm sure I never endangered any aircraft or pilot, but I'm also
sure
that some achieved less than optimal release altitude. There was no
tensionmeter, and throttle control was based on visual evaluation of
aircraft attitude and cable sag.

Many years later I had the chance to observe the operator of a modern
six-reel winch at Terlet. He was an artist at work, and he had the best
equipment.

I think winch launches are safe, as long as you have a cg hook. But, in
any
comparison to aerotow, the increased number of launches necessary to
achieve
sustained flight must be taken into account.

Ed Grens

If it's soarable, one launch should do most days. Most seasons I winch
launched regularly I can count on one hand the number second snaps taken per
season to soar away. Of course, _big wings_ do help, but that's another
thread;^) This season, I only took two aerotows to 2000agl. My other AT
releases were 1200 to 1700agl, that is, at or below winch height and near
enough to the airfield to presume had we been winching, getting away was
pretty likely. For a number of reasons we didn't winch much this season,
but when we did, we soared. This included thermals on New Year's Day and
wave on Feb 1 and thermals each subsequent winch day this season. Looks
like snow for November 1st though. Last Saturday would have been perfect as
lift was 10kts to 12K in a stiff NW breeze. The kind of day we get 2500+agl
on the wire.

Frank Whiteley

"F.L. Whiteley" wrote in message ...

If it's soarable, one launch should do most days. Most seasons I winch
launched regularly I can count on one hand the number second snaps taken per
season to soar away. Of course, _big wings_ do help, but that's another
thread;^) This season, I only took two aerotows to 2000agl. My other AT
releases were 1200 to 1700agl, that is, at or below winch height and near
enough to the airfield to presume had we been winching, getting away was
pretty likely. For a number of reasons we didn't winch much this season,
but when we did, we soared. This included thermals on New Year's Day and
wave on Feb 1 and thermals each subsequent winch day this season. Looks
like snow for November 1st though. Last Saturday would have been perfect as
lift was 10kts to 12K in a stiff NW breeze. The kind of day we get 2500+agl
on the wire.

Frank Whiteley
************************************************** ********************************
You guys should get a really good winch and pay someone to operate it
during the week. During the summer you could become a vacation
destination. Since there are nonstop flights from Europe to Denver
every day, you could probably get enough Brits and others to pay for
your winch and some rental gliders in a few summers.

This sounds like the place I learned to ground launch. Well, actually I
guess I got the basics down during a visit to New Zealand. In any event my
experience at the place was more positive as was the success of all of the
launches than your experience. "Lights on!" and all. I liked the rustic
feel of things, felt clear on and comfortable with the safety measures and
procedures in use, and my license no longer says aero tow only.

David Grah
Bishop, California

"JJ Sinclair" wrote in message
...
Gary,
I suspect you are considering winch launching for your club and I would
think
the biggest problem would be in getting club members, "Up to Speed" on
winch
operations.

In way of illustrating my point, allow me to tell a little story about a
local
soaring operation that is no longer in business. This outfit advertised,
get
your "Aero-Tow Only" restriction, removed from your glider licence. Come
to XXX
Soaring and we will check you out in about an hour, or so. This outfit had
a
2-33 with only a nose tow hook (mistake no. 1) They didn't use radios
(mistake
no. 2) The flight examiner weighed a good 300 lb. + your average student
at 200
lb. = 500 lb's in the 2-33 (mistake no. 3)

I was going to take the course, but had to wait for the student in front
of me
to get his check-out. The signal for "Start the launch" was, level the
wings
and flash the lights in the car located near the right wing tip. It went
something like this:

1. Level the wings & flash the lights------------Glider rolled about 10
feet
and stopped. winch operator stalled the winch.

2. Level the wings & flash the lights---------- Cable went, but glider
didn't
move. In the last attempt, wheel had rolled over cable and caused a
reverse
release.

3.Level the wings & flash the lights---------------Glider went about 100
feet
and stopped. Cable had "Kinked" in previous 2 attempts and then broke at a
kink.

-------------30 minute delay while Nico-Press & sleves are found and cable
is
spliced. With 3 attempts and no success, student is having second thoughts
and
opens canopy and starts to climb out. Instructor tells him, everything
will be
fine, this time, Get back in here.

4. Level the wings & flash the lights------------ Glider takes off, to the
wild
applause of all those assembled. Glider only gets 400 feet due to nose tow
hook
location. Glider makes a 90 right and a 180 left, lands and rolls right up
to
the starting point.

Attempts 5, 6 & 7 come off without a hitch and the Flight Examiner is
called
out (300 lbs)

Level the wings & flash the lights-------------- Glider takes off, but
only
gets 300 feet, makes a modified 90/180 and plunks it down hard, way down
the
runway.

I took this opportunity to silently disappear and my licence still reads,
Aero-Tow Only.
JJ Sinclair

Anyone who is seriously interested in ground launches should read and
understand Derek Piggott's great book "Ground Launches".

Thanks, Derek!

BJ

Gary Boggs wrote:

Someone must have already compared the safety of these tow launch methods.
What do the statistics show is the safer method of launch? Aero tow seems
to involve more inherent dangers to me. For one thing, there is just more
time for things to go wrong. What could be more dangerous than to tie tow
airplanes together and try to fly?

Gary Boggs

Try tying a glider to a truck to fly.


Gary Boggs wrote:
What could be more dangerous than to tie two
airplanes together and try to fly?

Gary Boggs

--

Peter D. Brown
http://home.gci.net/~pdb/
http://groups.yahoo.com/group/akmtnsoaring/

On Sat, 25 Oct 2003 12:43:35 -0700, "Gary Boggs"
wrote:

Someone must have already compared the safety of these tow launch methods.
What do the statistics show is the safer method of launch? Aero tow seems
to involve more inherent dangers to me. For one thing, there is just more
time for things to go wrong. What could be more dangerous than to tie tow
airplanes together and try to fly?

Gary Boggs


I've only done about two winch launches but have done several hundred
car tows and driven several hundred also.

Ground launches involve lots of wire, rope etc. It is probably a good
observation that the more rope you have the more trouble you can get
into! With one exception below.

I've had the glider run over the wire and tangle in the wheel well.
Not good as you now cannot release and depend on the tow driver..

Pilot reactions to a low altitude winch launch failure are utterly
critical. I suspect we've killed dozens if not hundreds over the years
this way around the world.

You may need more than one launch to get away(rare with aerotow). This
increases your launch risk exposure.

Someone mentioned the stresses in the wire and the glider. Both are
much lower in properly executed arotow.

Aero tow may have a higher exposure to an off airport landing in
unsuitable terrain but the failures seem to be much more rare than
winch wire breaks. If you don't use toy towplanes(less than 180HP)
then any place suitable for winching probably gives you the
opportunity to do a 180 or land straight ahead from an aerotow.

If you want gliding to be popular aerotow involves less running around
on the ground per flight hour.

Flying towplanes is more fun than driving a winch or tow
car.(Allegedly - I last sat in a towplane in 1971 writing down CHT's
for the cooling test for 4 tows in a row and haven't felt motivated to
get into a towplane since despite the aquisition of a PPL 9 years ago)

Aerotowing danger can be reduced by using a longer rope. One of the
local clubs around here tried it and liked it so much the towpilots
won't fly with short ropes. The long rope gives everyone more time to
handle upsets. I suspect the rise of the towplane upset accident
coincided with using shorter ropes.

Mike Borgelt

"Mike Borgelt" wrote in message
...

If you want gliding to be popular aerotow involves less running around
on the ground per flight hour.


A cable retrieve winch such as the one in use at the Long Mynd in the UK
makes a winch operation even slicker than aerotowing!

Ian

On Mon, 27 Oct 2003 05:41:06 +0000 (UTC), "tango4"
wrote:


"Mike Borgelt" wrote in message
.. .

If you want gliding to be popular aerotow involves less running around
on the ground per flight hour.


A cable retrieve winch such as the one in use at the Long Mynd in the UK
makes a winch operation even slicker than aerotowing!

Ian



So how many winch operations involve two people?
I've had tows where the only people present were the tow pilot and the
glider pilot. Least I got with auto tow was three. Both were no radio
ops.

And for you guys who operate on nice green grass airfields which allow
things like cable retrieve winches - it don't happen in Oz.

And lastly we did have a winch driver killed during a winch launch a
few years ago. The wire (basically high tensile single strand fencing
wire) shattered as it was being reeled in after the glider released
and one of the pieces of shrapnel hit the winch driver in the upper
torso and he died shortly thereafter before anyone got to the winch.
The lexan shield had been bought but not installed.

My favourite launch method involves a motor in the glider.

Mike Borgelt

"Mike Borgelt" wrote in message
.. .

And for you guys who operate on nice green grass airfields which allow
things like cable retrieve winches - it don't happen in Oz.

***********
You have obviously never been to the Long Mynd - I have heard it described
rather unkindly) as " a barely levelled granite hilltop".

The retrieve system ( a small winch pulls the cable back to the launch
point) originated out of necessity many many years ago when the airfield was
much smaller and the winch had to be positioned outside the boundary. The
cable crossed a deep, (approx 15/20 ft) gully at the airfield boundary and
then on up along a slope covered in bracken and heather, any other method of
retrieving the cable was impracticable. However the system was so efficient
in terms of launch rates that it has continued to this day even though the
airfield is now big enough to site the winch within the boundary. There is
of course a small penalty in terms of launch height but this is of little
significance.

On Mon, 27 Oct 2003 11:59:17 -0000, "Silent Flyer" ]
wrote:


"Mike Borgelt" wrote in message
.. .

And for you guys who operate on nice green grass airfields which allow
things like cable retrieve winches - it don't happen in Oz.

***********
You have obviously never been to the Long Mynd - I have heard it described
rather unkindly) as " a barely levelled granite hilltop".

Actually I have in 1988.
The surface looked pretty good compared to most Oz airfields. There
are one or two which I've jokingly said you would fail an outlanding
check if you picked the airfield.

I'm sure there are good statistics available for the safety of winch
vs aerotow but nobody has come up with them.

Winching is cheaper for training but has anyone noticed that gliding
is shrinking worldwide? Perhaps the old way of doing business is no
longer successful?

I think we need to realise that gliding is a sport for *pilots*.

First turn a newcomer into a pilot.

There is a wonderful array of small light aircraft and /or
motorgliders available nowadays at very reasonable prices. In Oz a
Pipistrel Sinus costs about the same as a new ASK21 and for the
purposes the K21 would be mostly used for (primary training) the Sinus
might be not quite as good a sailplane but will more than adequately
do the job and lets you teach cross country navigation, outlanding
field selection etc as well as being a not bad two seat bugsmasher.
Combine training in one of these with motivational rides with cross
country pilots in high performance two seat gliders(minimum - Janus,
Duo etc preferably with self launch or turbo to prevent outlandings)
and I think you might have a 21st Century soaring movement that might
have a fighting chance of actually retaining the people that come to
it.

Mike Borgelt