Safety of winch launch vrs. aero tow?
Gary Boggs
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
Peter Seddon
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" <gary....@charter.net> wrote in message
news:vplkja9...@corp.supernews.com...
Chris Nicholas
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.
Mark Navarre
"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
-
Eric Greenwell
glide...@aol.com.post 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)
Bob Johnson
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
Bill Daniels
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
BTIZ
coordination..
BT
"Bob Johnson" <robj...@cox.net> wrote in message
news:3F9B3265...@cox.net...
Bob Johnson
BJ
Bob Johnson
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
required in a winch launch, and the faster acceleration, and the fact that
you are in a position to land on the runway that you are using at all times,
the winch launch would be safer, but I still see no statistics! Come on
folks, someone surly has crunched the numbers. Training is crucial in both,
but what I'm looking for is numbers, I have plenty of opinions myself.
Boggs
"Bill Daniels" <n22...@earthlink.net> wrote in message
news:R3Hmb.2522$Px2...@newsread4.news.pas.earthlink.net...
Bill Daniels
> I like all these points and I suspect that because of the short time
> required in a winch launch, and the faster acceleration, and the fact that
> you are in a position to land on the runway that you are using at all
times,
> the winch launch would be safer, but I still see no statistics! Come on
> folks, someone surly has crunched the numbers. Training is crucial in
both,
> but what I'm looking for is numbers, I have plenty of opinions myself.
>
> Boggs
OK, the BGA accident database is available on the web. The database is
searchable for flights that began with a winch launch. Note, however, that
most of the accidents in this section do not relate directly to winch
launch.
I think that there were only three or four accidents over a ten year period
that actually happened during the winch launch. The rest were accidents
that happened later in a flight that began with a winch launch.
It seems to me that if winch launch accident data is hard to come by, that
in itself is good news. If accidents happened frequently, there would be
lots of hard data.
Bill Daniels
JJ Sinclair
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
Andreas Maurer
>I took this opportunity to silently disappear and my licence still reads,
>Aero-Tow Only.
I have to admit it: I'm impressed.
They really made every mistake that is possible. Thiw "insch launch"
attempts had as much in common with winch launching as a 2-33 has in
common with a Boeing 747.
Bye
Andreas
Mark Navarre
>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.
This brings up a point I left out of my original post. The SITE must be
suitable for winch launching. If the site has a short runway, or obstructions,
then the option to release and land straight ahead may be limited. Of course
this applies to aerotow as well.
>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.)
If the winch operator does not apply adequate power for rotation and climb
early in the launch, the window of opportunity to abort safely closes quickly
and leaves unsuitable options.
>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.
I wholeheartedly agree that training, and practice, are of great importance. I
had a winch launch accident early this year in which training played a large
part. Also reaction time, and the limited suitability of the site for winch
launching.
I will give a brief description of the accident:
I did not brief the winch driver on my launch requirements (mistake 1), my
glider had the highest wingloading of any there that day.
The initial acceleration from a stop was weak enough in comparison to all my
previous training on this winch to make the hair on the back of my neck stand
up. I had enough room to wait for more power (mistake 2) but was too low and
slow to wag wings. I briefly pulled back on the stick to see if there was any
tension on the cable, maybe the winch had redlined in a lower gear (the winch
in question has known issues, mistake 3). I felt the tension completely go
away, pulled the release and pushed the nose over. I was not aggressive with
the push over (mistake 4), but altitude was only 50-75 feet and the glider was
just above stall, so not enough room to gain speed, no room to land straight
ahead, and insufficient altitude to complete a turn to the right for a landing
on the abort runway.
I dragged the right wing and ground looped, breaking the tail boom of my
glider, and narrowly missed a Toyota truck that was parked in an unsafe area.
During debrief, I found out that the winch driver saw the retrieve chute
balloon immediately and thought I released so chopped the winch power. Chute
blossoming was common that day on previous launches due to improper chute
rigging (mistake 5) and this was probably exaggerated by the lack of full power
during the initial part of the launch. The site has about 1000 feet of usable
straight ahead runway, but it is downhill from glider to winch, and a portion
is steep enough so as to be impossible to walk uphill if the dirt is wet. The
abort runway is at a right angle to the launch runway, undulates in elevation
30-40 feet, and has a narrow spot about 60 feet wide bordered by trees and
bushes.
The dimensions of the site are such that there is a point in the launch when
you may be too high to land straight ahead, too low to continue into the ridge
lift, and too low to make the landable portion of the abort runway. The
situation is worse for higher wingloading gliders (I fly an ASW20) than are
typically flown at this site. Some of you may have guessed the site by now, it
is Torrey Pines, California. Having had this experience, I would fly there
again, but only after addressing the training and briefing issues mentioned.
The configuration of this site requires extra special attention to launch
procedures, but the satisfaction of flying at such a unique and historic
location is well worth it.
Ralph Jones
>
>I took this opportunity to silently disappear and my licence still reads,
>Aero-Tow Only.
I have a co-worker who's still around because he made the same shrewd
decision in connection with a bungee-jumping operation...
rj
Bob Johnson
understand Derek Piggott's great book "Ground Launches".
Thanks, Derek!
BJ
Pete Brown
>
> 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/
Mike Borgelt
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
Bill Daniels
"JJ Sinclair" <jjgl...@aol.com> wrote in message
news:20031026100410...@mb-m11.aol.com...
What JJ experienced is, unfortunately, an all too common experience in the
USA.
A bunch of guys, (it's usually guys) get together and decide to winch launch
gliders. ("How hard can it be?" "We can teach ourselves...") They start
with poor equipment, a bad site, no experience or training and proceed to
scare themselves badly...or worse.
They then decide that the problem is winch launch (It doesn't work, low
releases, lots of hassles, etc..) and then go back to air tow.
I've flown tugs and driven winches - I'll take winches for fun. I've flown
lots of air tow and been scared on plenty of occasions. I've flown lots of
winch launches and rarely had one go wrong. If anybody wants a winch
experienced CFI-G for a week of winch training, email me. I might be
available.
BTW, How about some of our British and European friends with lots of winch
experience jumping in here?
Bill Daniels
Stefan
>> BTW, How about some of our British and European friends with lots of winch
> experience jumping in here?
I can't speak for others, but I read this thread, shaked my head and
simply didn't feel like commenting. Seldom I have seen a discussion
which showed so clearly plain ignorance.
In a word: If done correctly, winch launching is safe, cheap and fun. It
is certainly much (much!) cheaper than aero-tow. It is certainly much
more fun. And it's easier, too.
The only dangerous moment for the pilot is at the very beginning of the
pull. It is very very very important not to pull too early or too
briskly. Stalling the glider at this altitude is lethal. Once
established in the climb, make sure you have always enough speed to pull
over if the rope breaks. Everything else is very easy and very safe.
There *are* rope breaks, but they are very much a non-event. Either you
have enough room to land straight, or you have enough altitude to do a
180 or a short circuit.
Winch launching has much more safety issues for the ground crew and
spectators than for the pilot. Be sure to have an experienced person
show you safe procedures.
Of course, an experienced winch driver helps a lot, too. At our club, a
new winch driver must do 50 launches under supervision befor he's
allowed to winch alone. We never had a winch accident in 40 years.
Stefan
Stefan
>> BTW, How about some of our British and European friends with lots of
winch
>
> experience jumping in here?
I can't speak for others, but I read this thread, shaked my head and
simply didn't feel like commenting. Seldom I have seen a discussion
which showed so clearly plain ignorance.
In a word: If done correctly, winch launching is safe, cheap and fun. It
is certainly much (much!) cheaper than aero-tow. It is certainly much
more fun. And it's easier, too.
The only dangerous moment for the pilot is at the very beginning of the
pull. It is very very very important not to pull too early or too
briskly. Stalling the glider at this altitude is lethal. Once
established in the climb, make sure you have always enough speed to push
Bill Daniels
"Stefan" <stefan@mus._INVALID_.ch> wrote in message
news:3f9c5e76$1...@news.swissonline.ch...
Bill Daniels
E. A. Grens
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
John Giddy
| A bunch of guys, (it's usually guys) get together and
decide to winch launch
| gliders. ("How hard can it be?" "We can teach
ourselves...") They start
| with poor equipment, a bad site, no experience or training
and proceed to
| scare themselves badly...or worse.
|
| They then decide that the problem is winch launch (It
doesn't work, low
| releases, lots of hassles, etc..) and then go back to air
tow.
|
| I've flown tugs and driven winches - I'll take winches for
fun. I've flown
| lots of air tow and been scared on plenty of occasions.
I've flown lots of
| winch launches and rarely had one go wrong. If anybody
wants a winch
| experienced CFI-G for a week of winch training, email me.
I might be
| available.
|
| BTW, How about some of our British and European friends
with lots of winch
| experience jumping in here?
Not from UK or Europe, but Australia:
There are a number of clubs, ours included that usually
launch by winch.
In Oz, all gliding is controlled by The Gliding Federation
of Australia, under a delegation from CASA (the Aussie FAA)
GFA has a regulation setting the minimum length of field for
winch launching to 1200 metres (approx 4000 ft). This is to
avoid the possibility of a "non-manoeuvring" area, where, if
the cable breaks, there is insufficient length to land
straight ahead, and not high enough to do a modified circuit
and land normally.
There are standard procedures which are taught, involving
signals between the pilot and the winch driver, and
procedure for dealing with cable breaks. These are taught
and practiced during the winch launch training. There is an
agreed minimum number of launches (12) before sign-off for
anyone converting from aerotow.
Provided you have a good winch, with sufficient power, and
an experienced driver, it is a very safe and efficient way
to get into the air.
It is also quiet, which is a boon for those fields close to
built-up areas.
Cheers, John G.
tango4
"Mike Borgelt" <mbor...@borgeltinstruments.com> wrote in message
news:vfeopvosok0nr9vjl...@4ax.com...
>
> 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
John Mason
http://www.esgc.co.uk/BGAdata.htm
Search and study the reports. There is much written between the lines. If
you look at the number of accidents where the launch was originally a winch
launch you will find that a lot of accidents occur soon after the launch is
completed and are attributed to other factors but which would really not
have happened if they had aerotowed. (Rigging errors not found in the speed
of the launch, not watching airspeed and spinning after the launch because
of distraction with the high workload of the winch and not dealing with the
angle of attack in the launch properly and so on). It is not possible to
give clear cut statistics without a significant degree of human
interpretation and you will really need to make your own mind up. I am
certain winching is a lot more dangerous. There are more things that can go
wrong and if they can go wrong, they will given time.
"Gary Boggs" <gary....@charter.net> wrote in message
news:vpmlio...@corp.supernews.com...
Jona
Bob;
Right, I thik this is really imprtant.
On tow, at 200 ft over the far-boundary you need the confidence to
know the right thing to do and do it straight away while retaing air-speed.
On tows we take of saying to oursevles 'land-ahead if it breaks now' from 0
to 150 feet
but there is a sweaty bit between150 and 300 ft where the choices are less
attractive.
In a winch lanuch (probably becauseof more experience) I am never in this
sweaty "hope it don't break at just this second" position.
--
Jonathan
Mike Borgelt
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
Silent Flyer
> >"Mike Borgelt" <mbor...@borgeltinstruments.com> wrote in message
> >news:vfeopvosok0nr9vjl...@4ax.com...
>
> 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.
Owain Walters
my flying is from winch launching.
My club operates primarily from the winch launch. When
our club was a bit busier we completed anything up
to 120 winch launches a day.
Winch launching, like anything in flying, is completely
safe if people are trained properly. I am not going
to teach people how to winch launch over the internet
but I will say that the number one rule is never to
get yourself into a situation from which you can not
recover with the energy (whether kinetic or potential)
you have. Put simply - never climb steeply from the
ground, always maintain an shallow 'initial' climb
until you reach a safe height and speed.
Winch launching is more Labour intensive than aerotowing
as you need a winch-driver, a cable retrieve driver,
a competent and experienced person making the decisions
and supervising and a wingrunner. However, for a training
environment it is certainly much, much cheaper and
fosters a 'club' atmosphere as everyone relies on eachother
to make things happen.
I do not know any statistics of winching vs. aerotowing
and frankly I think that statistics are, in general,
irrelevant in gliding (just look at the US contest
finish stats, I counted 4 in the last 17 years but
people think this is an area out of control in the
US). But what I do know is that I have never been in
a situation where I could not land safely on the airfield
in the event of a launch failure and I have never just
cleared the boundary hedge by a matter of inches (my
gratitude to the tug pilot for not dumping me has been
expressed many times in the form of beer) in a Duo
full of water on a winch launch either.
Having said that,I also feel that aerotows are also
safe when given that the equipment is regularly inspected
(whether it be the tug or rope) and that the landing
options are fully researched/explained prior to take
off. I have never not considered an aerotow because
I felt it was unsafe.
I guess my point is that both types are utterly safe
if people are trained and have a plan if things go
wrong, again like most situations in flying.
Bill Daniels
"John Mason" <replytothe...@nospamthanks.com> wrote in message
news:bninqa$e6f$1...@hercules.btinternet.com...
> A good place for statistics is:
>
> http://www.esgc.co.uk/BGAdata.htm
>
> Search and study the reports. There is much written between the lines.
If
> you look at the number of accidents where the launch was originally a
winch
> launch you will find that a lot of accidents occur soon after the launch
is
> completed and are attributed to other factors but which would really not
> have happened if they had aerotowed. (Rigging errors not found in the
speed
> of the launch, not watching airspeed and spinning after the launch because
> of distraction with the high workload of the winch and not dealing with
the
> angle of attack in the launch properly and so on). It is not possible to
> give clear cut statistics without a significant degree of human
> interpretation and you will really need to make your own mind up. I am
> certain winching is a lot more dangerous. There are more things that can
go
> wrong and if they can go wrong, they will given time.
>
John, the only way to see the data in the way you suggest is with a
prejudiced eye. If a pilot can't fly a glider under stress or rig it
properly, he's just an accident looking for a place to happen. It doesn't
matter how the glider is launched.
Bill Daniels
Bert Willing
cable breaking near the winch under full power is something very, very
dangerous, so sitting on a winch without shielding is asking to be killed.
The min team for winch launches is the pilot, the winch driver and the wing
runner (the winch driver can retrieve the cables on his own if the winch has
properly working brakes on the drums). If pilot and winch driver are
suffiencently experienced, a chair may well replace the wingrunner (although
stating that in public may not be politically correct :-)
During winch launch, any accident is related to pilot errors so you can
basically keep the accident rate fairly low.
On aerotows you may have situations were a cable break *will* induce an
accident, and the pilot may just be able to influence the damage.
--
Bert Willing
ASW20 "TW"
"Mike Borgelt" <mbor...@borgeltinstruments.com> a écrit dans le message de
news:2hvppvs4f2lsf2qni...@4ax.com...
Martin Gregorie
<replytothe...@nospamthanks.com> wrote:
...snippage...
>(Rigging errors not found in the speed
>of the launch, not watching airspeed and spinning after the launch because
>of distraction with the high workload of the winch and not dealing with the
>angle of attack in the launch properly and so on).
...snippage...
None of these points are unique to winching.
- I've seen many more comments on r.a.s about failed aero tows
due to rigging errors than I've heard about for winching. To me this
says more about the safety culture (or lack of it) at different
sites than anything to do with the launch method.
- incorrect airspeed and stall/spin after release is just as possible
at the end of an aero tow if you overcook the climbing turn.
- AOA mis-management will be *much* more serious during an aero tow
on a CG hook than during a winch launch provided the appropriate
weak link is used. Think tug upset.
I launch both ways though I'll admit to many more winch than aero-tow
starts. I see very little difference in pilot stress levels or
workload between the launch methods in good conditions, but the
overall stress from an aero tow is larger, simply because you're on
tow for 5 minutes or more compared with the 30 seconds to get to the
top of the cable. If I'm flying something as sluggish in roll as a
G.103A in turbulent, windy conditions then winching has a much lower
work load than aero-tow.
This is my opinion entirely: I'm not speaking for anybody else or
trying to put words in their mouth.
--
martin@ : Martin Gregorie
gregorie : Harlow, UK
demon :
co : Zappa fan & glider pilot
uk :
Christian Husvik
John Mason wrote:
> (Rigging errors not found in the speed of the launch,
Whit??
Do forgive my clearly insufficient knowledge of the English
language, but what exactly does "rigging errors not found in the speed
of the launch" mean? And how would those have been found and corrected
if the launch subsequent to rigging had been by areotow rather than by
winch?
I mean: The fact that an aerotow takes longer time to complete does not
give you any more time _prior_ to launch, does it?
Christian 8-)