Discussion:
Winch accident in New Zealand, can low time student pilot be blamed?
(too old to reply)
Andre Volant
2004-12-03 22:15:53 UTC
Permalink
http://www.glidingmagazine.com/NewsArticle.asp?id=1371
http://www.glidingmagazine.com/
Correct "CG" release was used, which on PW5 is offsett forward of the
CG.
I was told that the nose hook is not allowed for winch towing of PW5.
That's what manual sais, but who knows why?
Which other gliders are not allowed to be winched by the nose?
I was told that PW5 has front and rear ballast weights, how
complicated is it?
Who is resposible for checking weight and ballance, if for example
student pilot has 3 hours (40 flights X 5min) of flight experience?
When does resposibility of flight instructor end?

Andre
Bill Daniels
2004-12-03 23:21:46 UTC
Permalink
Post by Andre Volant
http://www.glidingmagazine.com/NewsArticle.asp?id=1371
http://www.glidingmagazine.com/
Correct "CG" release was used, which on PW5 is offsett forward of the
CG.
As is supposed to be the case.
Post by Andre Volant
I was told that the nose hook is not allowed for winch towing of PW5.
That's what manual sais, but who knows why?
Because winching with a nose hook causes a glider to porpoise.
Post by Andre Volant
Which other gliders are not allowed to be winched by the nose?
Any glider with a CG hook. Many gliders are equipped with ONLY a CG hook.
Post by Andre Volant
I was told that PW5 has front and rear ballast weights, how
complicated is it?
Probably not complicated at all.
Post by Andre Volant
Who is resposible for checking weight and ballance, if for example
student pilot has 3 hours (40 flights X 5min) of flight experience?
There was nothing in the Gliding Magazine story about this level of
experience. However, 40 flights and 3:20 of instruction should have been
plenty for a rated pilot to make the transition to winch launch.

The pilot in command is always responsible for weight and balance.

This post and the Gliding Magazine story seems to suggest that there is
something wrong with the use of a CG hook. In fact, there is a great deal
wrong with NOT using a CG hook for winch launch.

A very FEW older gliders exhibit a behavior where the nose will pitch up
uncontrollably if the winch acceleration is too strong. These gliders
usually have high CG's, low CG hooks and small tail surfaces and/or all
moving tails that limit down elevator authority. Good winch drivers know
about them and reduce acceleration accordingly. I don't know if the PeeWee
exhibits these characteristics - since it is a modern design, I doubt that
it does.

The usual cause for accidents of this type is a pilot who starts a climb
before the glider achieves a safe airspeed. This can be compounded in
modern gliders which often require NO back pressure to enter the climb. If
the pilot in under the impression that a strong pull on the stick is
required to enter the climb, problems of this sort may result.

We need to wait the results of the investigation. Rushing to blame the
glider design is almost always the wrong thing to do.

Bill Daniels
Mal
2004-12-04 00:30:30 UTC
Permalink
I had a Hornet kite on me one time the winch driver saw it and gave it to
the winch.

The trim went to full back as I rotated as the aircraft has the stupidest
spring loaded trim system in the world for winch launching DANGER !

Does the PW5 have the same trim system says the guy was Asian so most of
them are light weights to add to his C of G problems.

Mal
Post by Bill Daniels
Post by Andre Volant
http://www.glidingmagazine.com/NewsArticle.asp?id=1371
http://www.glidingmagazine.com/
Correct "CG" release was used, which on PW5 is offsett forward of the
CG.
As is supposed to be the case.
Post by Andre Volant
I was told that the nose hook is not allowed for winch towing of PW5.
That's what manual sais, but who knows why?
Because winching with a nose hook causes a glider to porpoise.
Post by Andre Volant
Which other gliders are not allowed to be winched by the nose?
Any glider with a CG hook. Many gliders are equipped with ONLY a CG hook.
Post by Andre Volant
I was told that PW5 has front and rear ballast weights, how
complicated is it?
Probably not complicated at all.
Post by Andre Volant
Who is resposible for checking weight and ballance, if for example
student pilot has 3 hours (40 flights X 5min) of flight experience?
There was nothing in the Gliding Magazine story about this level of
experience. However, 40 flights and 3:20 of instruction should have been
plenty for a rated pilot to make the transition to winch launch.
The pilot in command is always responsible for weight and balance.
This post and the Gliding Magazine story seems to suggest that there is
something wrong with the use of a CG hook. In fact, there is a great deal
wrong with NOT using a CG hook for winch launch.
A very FEW older gliders exhibit a behavior where the nose will pitch up
uncontrollably if the winch acceleration is too strong. These gliders
usually have high CG's, low CG hooks and small tail surfaces and/or all
moving tails that limit down elevator authority. Good winch drivers know
about them and reduce acceleration accordingly. I don't know if the PeeWee
exhibits these characteristics - since it is a modern design, I doubt that
it does.
The usual cause for accidents of this type is a pilot who starts a climb
before the glider achieves a safe airspeed. This can be compounded in
modern gliders which often require NO back pressure to enter the climb.
If
the pilot in under the impression that a strong pull on the stick is
required to enter the climb, problems of this sort may result.
We need to wait the results of the investigation. Rushing to blame the
glider design is almost always the wrong thing to do.
Bill Daniels
John Giddy
2004-12-05 07:12:06 UTC
Permalink
Post by Bill Daniels
Post by Andre Volant
http://www.glidingmagazine.com/NewsArticle.asp?id=1371
http://www.glidingmagazine.com/
Correct "CG" release was used, which on PW5 is offsett forward of the
CG.
As is supposed to be the case.
Post by Andre Volant
I was told that the nose hook is not allowed for winch towing of PW5.
That's what manual sais, but who knows why?
Because winching with a nose hook causes a glider to porpoise.
Post by Andre Volant
Which other gliders are not allowed to be winched by the nose?
Any glider with a CG hook. Many gliders are equipped with ONLY a CG hook.
Post by Andre Volant
I was told that PW5 has front and rear ballast weights, how
complicated is it?
Probably not complicated at all.
Post by Andre Volant
Who is resposible for checking weight and ballance, if for example
student pilot has 3 hours (40 flights X 5min) of flight experience?
There was nothing in the Gliding Magazine story about this level of
experience. However, 40 flights and 3:20 of instruction should have been
plenty for a rated pilot to make the transition to winch launch.
The pilot in command is always responsible for weight and balance.
This post and the Gliding Magazine story seems to suggest that there is
something wrong with the use of a CG hook. In fact, there is a great deal
wrong with NOT using a CG hook for winch launch.
A very FEW older gliders exhibit a behavior where the nose will pitch up
uncontrollably if the winch acceleration is too strong. These gliders
usually have high CG's, low CG hooks and small tail surfaces and/or all
moving tails that limit down elevator authority. Good winch drivers know
about them and reduce acceleration accordingly. I don't know if the PeeWee
exhibits these characteristics - since it is a modern design, I doubt that
it does.
There have been a couple of incidents in OZ with PW-5s responding
badly to aggressive winch acceleration. I don't know the details
though.

Cheers, John G.
OscarCVox
2004-12-05 09:42:04 UTC
Permalink
At Lasham in the uk we use powerful winchea(450hp). A couple of makes of glider
have problems if the acceleration is too fierce initially.Typically they have a
Cof G hook mounted well aft, a high glider Cof G, high mounted wing (or the
main drag being relatively high), nose wheel or skid,and light weight.
If you watch them as the cable tighten the tail will bang down (sometimes
harder than you would like) This gives the wings a high angle of attack and the
glider will lift off with the tail skid still on the ground, straight into a
full climb. Quite often the pilot is just a passenger whilst this happens. Once
in the air and sufficient flying speed is reached the elevator will start to
become effective and he can regain control. The two makes that I have flown
that have this problem are the K8 and PW5.
We now teach pilots in the K8 to start the winch with full forward stick until
flying speed has been reached.
A couple of other factor that can make the problem worse. Strong headwind and
my pet hate, soft cushions. If a soft cushion is being used as a backrest in
these circumstances the acceleration and attitude will thow you back
compressing the cushion and not allowing full forward movement of the stick.
Also in the report it mentions a type of tow hook that sometimes jams under
tension, lethal in my opinion, change it.
F.L. Whiteley
2004-12-05 20:23:00 UTC
Permalink
Post by OscarCVox
At Lasham in the uk we use powerful winchea(450hp). A couple of makes of glider
have problems if the acceleration is too fierce initially.Typically they have a
Cof G hook mounted well aft, a high glider Cof G, high mounted wing (or the
main drag being relatively high), nose wheel or skid,and light weight.
If you watch them as the cable tighten the tail will bang down (sometimes
harder than you would like) This gives the wings a high angle of attack and the
glider will lift off with the tail skid still on the ground, straight into a
full climb. Quite often the pilot is just a passenger whilst this happens. Once
in the air and sufficient flying speed is reached the elevator will start to
become effective and he can regain control. The two makes that I have flown
that have this problem are the K8 and PW5.
We now teach pilots in the K8 to start the winch with full forward stick until
flying speed has been reached.
A couple of other factor that can make the problem worse. Strong headwind and
my pet hate, soft cushions. If a soft cushion is being used as a backrest in
these circumstances the acceleration and attitude will thow you back
compressing the cushion and not allowing full forward movement of the stick.
Also in the report it mentions a type of tow hook that sometimes jams under
tension, lethal in my opinion, change it.
Oly 463 is another tail stander. I thought soft cushions were banned within
the BGA after a fatality attributed to them.

Frank Whiteley
OscarCVox
2004-12-06 09:35:57 UTC
Permalink
Post by OscarCVox
If a soft cushion is being used as a backrest
in
Post by OscarCVox
these circumstances the acceleration and attitude will thow you back
compressing the cushion and not allowing full forward movement of the
stick.
I thought soft cushions were banned within
the BGA after a fatality attributed to them.
I believe that they are, but you still see the occasional idiot using them for
"comfort".
I mentioned it because this is an international newsgroup.
Ian Johnston
2004-12-06 14:43:39 UTC
Permalink
On Fri, 3 Dec 2004 23:21:46 UTC, "Bill Daniels" <***@comcast.net>
wrote:

: A very FEW older gliders exhibit a behavior where the nose will pitch up
: uncontrollably if the winch acceleration is too strong. These gliders
: usually have high CG's, low CG hooks and small tail surfaces and/or all
: moving tails that limit down elevator authority. Good winch drivers know
: about them and reduce acceleration accordingly.

Given an over enthusiastic launch, the Pirat will happily take off,
fly level and then rotate into a full climb, and there is absolutely
nothing the pilot can do about it. Except attend to the education of
the winch driver...

One of my pets hates is the belief that it's a good thing to hold down
the tail of some gliders for a winch launch. It isn't. All that
happens is that as soon as the tail holder lets go, the nose slams
down, then the tail slams down even more violently on the rebound.

Ian

--
Gary Boggs
2004-12-06 16:14:16 UTC
Permalink
Holding the tail down works very well with an SGS 2-33 in any situation
where the initial pull is strong. We use that technique in all our ground
launches when we have an extra person. It might not work well with other
ships but it is definitely the preferred method with the 2-33.
Post by Ian Johnston
One of my pets hates is the belief that it's a good thing to hold down
the tail of some gliders for a winch launch. It isn't. All that
happens is that as soon as the tail holder lets go, the nose slams
down, then the tail slams down even more violently on the rebound.
Ian
--
Bill Daniels
2004-12-06 16:19:07 UTC
Permalink
Right. It works with a 2-33 but it's disaster with a Grob 103. A G103
seems to fly the launch just fine without pilot input as does the L23.

Bill Daniels
Post by Gary Boggs
Holding the tail down works very well with an SGS 2-33 in any situation
where the initial pull is strong. We use that technique in all our ground
launches when we have an extra person. It might not work well with other
ships but it is definitely the preferred method with the 2-33.
Post by Ian Johnston
One of my pets hates is the belief that it's a good thing to hold down
the tail of some gliders for a winch launch. It isn't. All that
happens is that as soon as the tail holder lets go, the nose slams
down, then the tail slams down even more violently on the rebound.
Ian
--
goneill
2004-12-04 02:45:41 UTC
Permalink
I belong to the club where this happened .
The inquiry is still going on but from comments made by
people actually there when it happened.
The pilot had already flown earlier in the day in the same glider.
The witnesses said the pilot rotated early and was a bit steep in the
initial climb but then started to turn right when in full climb
at around 300 ft, the deviation to the right continued until back release
occurred when the PW5 promptly rolled into a spin.
Partial recovery seemed to happen and the PW5 landed straddling a
driveway. The farm type 7 wire fences on either side of that driveway
acted like arrestor wires.The pilot has 2 broken ankles a
broken arm and other minor injuries.The pilot I think is from Hong Kong
and I believe has already been flown home.
The PW5 is known to want to go to full climb quickly if not prevented
but I know a Nimbus 2 will do exactly the same if winched a bit quick so
don't blame the glider ,this accident has the look of pilot error.
A lot of the training here is on the 2 seat PW6 so type conversion problems
are likely not an issue.
gary
Post by Andre Volant
http://www.glidingmagazine.com/NewsArticle.asp?id=1371
http://www.glidingmagazine.com/
Correct "CG" release was used, which on PW5 is offsett forward of the
CG.
I was told that the nose hook is not allowed for winch towing of PW5.
That's what manual sais, but who knows why?
Which other gliders are not allowed to be winched by the nose?
I was told that PW5 has front and rear ballast weights, how
complicated is it?
Who is resposible for checking weight and ballance, if for example
student pilot has 3 hours (40 flights X 5min) of flight experience?
When does resposibility of flight instructor end?
Andre
Stefan
2004-12-04 12:22:01 UTC
Permalink
Post by goneill
The witnesses said the pilot rotated early and was a bit steep in the
initial climb but then started to turn right when in full climb
Judging from my lawn-chair, I'm tempted to say: Watch your airspeed!

Stefan
Robert Ehrlich
2004-12-04 21:40:04 UTC
Permalink
----------
Post by Stefan
Post by goneill
The witnesses said the pilot rotated early and was a bit steep in the
initial climb but then started to turn right when in full climb
Judging from my lawn-chair, I'm tempted to say: Watch your airspeed!
Not only the airspeed. As the load factor may be high despite the pilot
doesn't feel it, the angle of attack may be near the stall angle with a
speed well over the normal 1g stall speed. Maybe the only symptom of the
near stall angle of attack in this case is the loss of roll damping and
the ensuing tendancy to drop a wing which is much more easily countered
with the rudder than the elevator. The fact that the glider involved in
the accident started to bank to the right may be an indication that this
was the case.
Mark James Boyd
2004-12-04 17:10:10 UTC
Permalink
On aerotow, my top two critical items on the PW-5 were

trim set forward
spoilers locked

I'd love to know where this PW-5 trim was set. Anyone look at it after the
accident? I used to set 3 for launch, and use 7 or 8 (edge of stall) for
thermalling only.
Post by goneill
I belong to the club where this happened .
The inquiry is still going on but from comments made by
people actually there when it happened.
The pilot had already flown earlier in the day in the same glider.
The witnesses said the pilot rotated early and was a bit steep in the
initial climb but then started to turn right when in full climb
at around 300 ft, the deviation to the right continued until back release
occurred when the PW5 promptly rolled into a spin.
Partial recovery seemed to happen and the PW5 landed straddling a
driveway. The farm type 7 wire fences on either side of that driveway
acted like arrestor wires.The pilot has 2 broken ankles a
broken arm and other minor injuries.The pilot I think is from Hong Kong
and I believe has already been flown home.
The PW5 is known to want to go to full climb quickly if not prevented
but I know a Nimbus 2 will do exactly the same if winched a bit quick so
don't blame the glider ,this accident has the look of pilot error.
A lot of the training here is on the 2 seat PW6 so type conversion problems
are likely not an issue.
gary
Post by Andre Volant
http://www.glidingmagazine.com/NewsArticle.asp?id=1371
http://www.glidingmagazine.com/
Correct "CG" release was used, which on PW5 is offsett forward of the
CG.
I was told that the nose hook is not allowed for winch towing of PW5.
That's what manual sais, but who knows why?
Which other gliders are not allowed to be winched by the nose?
I was told that PW5 has front and rear ballast weights, how
complicated is it?
Who is resposible for checking weight and ballance, if for example
student pilot has 3 hours (40 flights X 5min) of flight experience?
When does resposibility of flight instructor end?
Andre
--

------------+
Mark J. Boyd
Andrew Sparks
2004-12-07 14:26:36 UTC
Permalink
As a low time pilot myself - but most of it on winch starts - I can
perhaps offer the following (not having read the reports - just this
thread):
- in the "action" of a fast winch launch - compared to tow - it can be
easy to fixate on rotation into (too steep) climb and airspeed and not
to check simple things like are my wings level. Sounds like to the
pilot too far off level and "fell off the side" of the climb into a stall
- some correction for crosswind is usually only initated above 100m
check (300 ft AGL) - at least that it what I've been taught
Andrew
Post by goneill
I belong to the club where this happened .
The inquiry is still going on but from comments made by
people actually there when it happened.
The pilot had already flown earlier in the day in the same glider.
The witnesses said the pilot rotated early and was a bit steep in the
initial climb but then started to turn right when in full climb
at around 300 ft, the deviation to the right continued until back release
occurred when the PW5 promptly rolled into a spin.
Partial recovery seemed to happen and the PW5 landed straddling a
driveway. The farm type 7 wire fences on either side of that driveway
acted like arrestor wires.The pilot has 2 broken ankles a
broken arm and other minor injuries.The pilot I think is from Hong Kong
and I believe has already been flown home.
The PW5 is known to want to go to full climb quickly if not prevented
but I know a Nimbus 2 will do exactly the same if winched a bit quick so
don't blame the glider ,this accident has the look of pilot error.
A lot of the training here is on the 2 seat PW6 so type conversion problems
are likely not an issue.
gary
Post by Andre Volant
http://www.glidingmagazine.com/NewsArticle.asp?id=1371
http://www.glidingmagazine.com/
Correct "CG" release was used, which on PW5 is offsett forward of the
CG.
I was told that the nose hook is not allowed for winch towing of PW5.
That's what manual sais, but who knows why?
Which other gliders are not allowed to be winched by the nose?
I was told that PW5 has front and rear ballast weights, how
complicated is it?
Who is resposible for checking weight and ballance, if for example
student pilot has 3 hours (40 flights X 5min) of flight experience?
When does resposibility of flight instructor end?
Andre
Chris OCallaghan
2004-12-04 14:39:25 UTC
Permalink
Andre,

Cg hooks require more pilot attention as the tow line/wire does not
provide any additional stability as is the case with a nose hook. In
fact, it can severly aggrevate misuse of the controls. This is why a
nose hook is always preferred for aerotow.

For ground launches using a nose hook, the principal problem would
appear to be overpowering the elevator. The higher your angle of
climb, the more elevator would be required to keep the cable from
pitching the nose down. (A cg hook would not affect stick pressures
since the force vector is through the glider's cg, ie, no/little
forward pitch moment). Aside from load and structure problems, here's
the real killer. If the cable breaks, you have nearly full rear stick
applied. If not release immediataley, you are likely to enter a low
altitude, accelerated stall. Bad news.

I suspect that the problem related in the article was an acceleratated
stall while still on the cable. This would explain loss of control and
back release. It's not hard to see how an inexperienced pilot might
abuse the controls during launch and wind up in just such a situation.
Post by Andre Volant
http://www.glidingmagazine.com/NewsArticle.asp?id=1371
http://www.glidingmagazine.com/
Correct "CG" release was used, which on PW5 is offsett forward of the
CG.
I was told that the nose hook is not allowed for winch towing of PW5.
That's what manual sais, but who knows why?
Which other gliders are not allowed to be winched by the nose?
I was told that PW5 has front and rear ballast weights, how
complicated is it?
Who is resposible for checking weight and ballance, if for example
student pilot has 3 hours (40 flights X 5min) of flight experience?
When does resposibility of flight instructor end?
Andre
Charles Yeates
2004-12-05 01:17:51 UTC
Permalink
Post by Chris OCallaghan
I suspect that the problem related in the article was an acceleratated
stall while still on the cable. This would explain loss of control and
back release. It's not hard to see how an inexperienced pilot might
abuse the controls during launch and wind up in just such a situation.
Agree --
In Nova Scotia, at a winch only club with 20+ years experience, a fatal
accident occurred during a launch. The pilot accelerated and took off
normally, then rotated toward full climb sooner than we teach. The HP18
had a high speed stall and spun rapidly on the wire and into the ground
from no more than 300 feet. This was the pilot's second launch of the
day. The first was normal. Too steep too soon can result in a high speed
stall.

I winch launched my PW5 at this home club for five years -- no problems
but I paid close attention to maintaining control of the flight
attitude and launch profile -- as I did on all the other ships that the
club operates.

The club Ka8 was noticeably harder to control at the begining of a
launch but we never had a launch accident with either glider type.
Ian Johnston
2004-12-06 14:40:59 UTC
Permalink
On Fri, 3 Dec 2004 22:15:53 UTC, ***@yahoo.com (Andre
Volant) wrote:

: I was told that the nose hook is not allowed for winch towing of PW5.
: That's what manual sais, but who knows why?
: Which other gliders are not allowed to be winched by the nose?

Most of them. Two main reasons: you get one heck of a down pull right
at the front as the launch proceeds and nose hooks don't have back
releases.

In fact, the Pirat is the only glider I have come across in which
winching with the nose hook is explicitly allowed in the pilot
handbook: you are told to use full forward trim (gets the trim tab up:
every little helps) and to expect only around 60% of the launch height
you'd get with the belly hook. And it still doesn't have a back
release...

: Who is resposible for checking weight and ballance, if for example
: student pilot has 3 hours (40 flights X 5min) of flight experience?

The pilot. No doubt. No argument.

: When does resposibility of flight instructor end?

In one sense, when s/he gets out the back seat. In another sense, as
long as the pilot is flying.

Ian
For Example John Smith
2004-12-06 21:06:21 UTC
Permalink
Post by Andre Volant
http://www.glidingmagazine.com/NewsArticle.asp?id=1371
http://www.glidingmagazine.com/
I was told that PW5 has front and rear ballast weights, how
complicated is it?
The PW5 has compartments for lead shot ballast under the seat pan.
I don't believe there's any official rear ballast position, but I do know of
pilots who have put a pound or two of lead sheets in the flat area where the
horizontal stabilizer attaches.
It's not a complicated arrangement, but any addition of ballast in either
position would be specific to the pilot and should be done by the pilot
IMHO.

I've been flying for about 7 years and in my estimation there's good news
and bad news in answer to the question "can low time student pilot be
blamed?"
The bad news is yes, in most every accident I've read about the pilot
_in_command_ could have done something to prevent the accident.
The good news is we have in our own hands and heads the ability to prevent
the accident that will kill us.

Brent
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