Safety of winch launch vrs. aero tow?

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

Hi

Having both winched and aerotowed several times!!! I find an aerotow less
demanding, everything happens very quickly on a winch wire.

Peter S
DLA


"Gary Boggs" wrote in message
...
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

It all depends on what you mean by statistics, and safer.

Harry Enfield (a UK comedian): "Flying is safe, you don't want to worry
about flying; it's crashing that's dangerous."

Winch launching and aerotowing are safe, it's the consequence of
mismanaging an abnormality that's dangerous.

Winch launches yield few accidents in themselves (e.g. occasional ground
loops); a competent pilot should have been trained in, and able to cope
with, a variety of abnormal situations such as cable breaks, too slow,
gradual power failure, etc. All of these are manageable with competent
handling. If badly handled, however, any can lead to a bad, even fatal,
accident. E.g. turning too low and slow after a cable break, leading to
a classic spin. But is that counted as a winch accident, or a failure to
monitor speed while turning close to the ground, i.e. a flight or
pre-landing accident? You may find that statistics are not compiled in
comparable ways over time, or between one club (or organisation, or
country) and another.

Aerotowing is more likely to kill the tug pilot than the glider pilot if
it goes wrong, i.e. the "tug upset" accident which seemed to start in
the 1970's. In terms of accidents per 100,000 launches, however, these
are rare. Oversimplifying to some extent, the only really dangerous
part of an aerotow where the competent glider pilot has little chance of
avoiding a bad accident is a rope break or power failure over bad
terrain, which is only applicable to a small proportion of sites (in my
experience).

Either method can lead very rarely to harm to second or third parties. I
know of one fatality to a ground handler associated with cable launch
operations (UK, 1970's). I know of other injuries from falling cables,
including one dead cow. There has probably been at least one instance
of somebody walking into a tug propellor, somewhere in the world. I
recall one tug accident where a child was a passenger in the tug and was
killed when it spun in (there is an argument for never carrying extra
people in the tug unless required for operational or training reasons -
it adds to the risk by reducing climb performance and increasing the
period of greatest hazard, as well as adding to the number of people at
risk in the operation - but many clubs seem to regard that as
acceptable).

There are some underlying causes of accidents that are more likely to be
found in the winch launch phase that in an aerotow - but could anyway
happen in the subsequent flight. A loose seat back leading to unintended
pitch up, and structural failure, are two I have heard of - winch
launches usually involve greater stresses and more extreme attitudes
than aerotows, unless the latter involve rotor or other adverse
conditions. But the subsequent flight could also have included
turbulence or other stress-inducing circumstances with equally tragic
results, if the problem had survived the launch phase - so should those
be counted as launch accidents?

Beware of the raw statistics.

Chris N.

Errors on the part of the winch driver may leave the glider pilot completely
"hung out to dry" with no risk whatsoever to the winch driver. During aerotow,
the tug pilot is not likely to make mistakes that might kill himself. The
incentive for a safe tow is thus higher for aerotow, because the tow pilot has
built-in accountability. I have driven the winch, and launched my glider by
tug, winch, and auto-tow. I prefer airtow over the other methods, but all can
be safe with proper training and pre-launch briefing.
-
Mark Navarre
ASW-20 OD
California, USA
-

In article ,
says...
Errors on the part of the winch driver may leave the glider pilot completely
"hung out to dry" with no risk whatsoever to the winch driver. During aerotow,
the tug pilot is not likely to make mistakes that might kill himself.

Of course, the winch operator can't make mistakes that will kill him
or her. In addition, I think a major advantage of the winch launch is
the glider pilot can't kill the winch operator! Unfortunately, tug
pilots have put themselves at risk (and been killed because of it)
because of a concern for the glider pilot that is putting the tug
pilot at risk. Sometimes this is just running out of fuel because they
don't want to slow down the launch line; sometimes it's hesitating to
pull the release when low over bad ground.

Personally, I suspect the glider pilot is a little better off behind a
towplane (might be my US training bias), but I have no idea if the
statistics agree with me. The UK and Europe might be able to do a good
comparison, but in the US, winch launching is done in only a few
places.
--
!Replace DECIMAL.POINT in my e-mail address with just a . to reply
directly

Eric Greenwell
Richland, WA (USA)

Mark,

I don't think the winch op can't leave anybody out to dry except maybe
himself. If the glider pilot doesn't like what's happening, pull
release, pull spoilers, land straight ahead.

BJ

Mark Navarre wrote:

Errors on the part of the winch driver may leave the glider pilot completely
"hung out to dry" with no risk whatsoever to the winch driver. During aerotow,
the tug pilot is not likely to make mistakes that might kill himself. The
incentive for a safe tow is thus higher for aerotow, because the tow pilot has
built-in accountability. I have driven the winch, and launched my glider by
tug, winch, and auto-tow. I prefer airtow over the other methods, but all can
be safe with proper training and pre-launch briefing.
-
Mark Navarre
ASW-20 OD
California, USA
-

"Gary Boggs" wrote in message
...
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 have done a whole lot of both and, given a choice, I'll take winch launch.

Yes, things happen fast on a winch launch but then the launch is over in
30-40 seconds so the risk exposure is short - with air tow, you are at risk
a least ten times as long. Air tow in turbulent air is fatiguing - you will
never get tired in a 35 second winch launch.

If you don't like the way a winch launch is going, release and land. You
can do that with a winch launch because you should always be in a position
to land back on the runway - I can't say that is always true with air tow.

Air tow is formation flying - involving two extremely mis-matched aircraft -
with a rope tying them together. This requires highly developed flying
skills to do safely. We teach this to pre-solo students. (I wonder how we
get away with it.) Winch launch can easily be taught to pre-solo pilots
since it is a simple, repetitive task.

Air tow has two aircraft at risk and at least two pilots - winch launch has
only one aircraft at risk.

Winch launch accelerates the glider far faster than air tow so dropping a
wing due to insufficient aileron control is unlikely. (Of course, you can
still drop a wing due to incompetence with unhappy results.)

In both cases, the training of the pilots and launch crews have a lot to due
with overall safety. There is ample opportunity for either to come to a bad
end. With equally good training, I think winch launch is safer.

But, lets face it - winch launch LOOKS scary to a pilot trained that a steep
nose-up attitude near the ground is dangerous. It isn't dangerous but it
sure looks that way.

Bill Daniels

and then you'll be nearer the winch operator for a little face to face
coordination..

BT

"Bob Johnson" wrote in message
...
Mark,

I don't think the winch op can't leave anybody out to dry except maybe
himself. If the glider pilot doesn't like what's happening, pull
release, pull spoilers, land straight ahead.

BJ

Mark Navarre wrote:

Errors on the part of the winch driver may leave the glider pilot
completely
"hung out to dry" with no risk whatsoever to the winch driver. During
aerotow,
the tug pilot is not likely to make mistakes that might kill himself.
The
incentive for a safe tow is thus higher for aerotow, because the tow
pilot has
built-in accountability. I have driven the winch, and launched my
glider by
tug, winch, and auto-tow. I prefer airtow over the other methods, but
all can
be safe with proper training and pre-launch briefing.
-
Mark Navarre
ASW-20 OD
California, USA
-

No man, you need to do one and then you'll understand what I'm saying.

BJ


BTIZ wrote:

and then you'll be nearer the winch operator for a little face to face
coordination..

BT

"Bob Johnson" wrote in message
...
Mark,

I don't think the winch op can't leave anybody out to dry except maybe
himself. If the glider pilot doesn't like what's happening, pull
release, pull spoilers, land straight ahead.

BJ

Mark Navarre wrote:

Errors on the part of the winch driver may leave the glider pilot
completely
"hung out to dry" with no risk whatsoever to the winch driver. During
aerotow,
the tug pilot is not likely to make mistakes that might kill himself.
The
incentive for a safe tow is thus higher for aerotow, because the tow
pilot has
built-in accountability. I have driven the winch, and launched my
glider by
tug, winch, and auto-tow. I prefer airtow over the other methods, but
all can
be safe with proper training and pre-launch briefing.
-
Mark Navarre
ASW-20 OD
California, USA
-

Here's an interesting point of reference:

Proper pilot life-saving reaction to winch line breaks, op inattention,
winch engine failure, or op incapacitation is routinely taught in ground
launch training.

How many airtow instructors pull the release on their student at 200 ft
over the outbound fence? Just once? Several times?

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