CG hook on aero tows??

Cliff Hilty wrote [snip] "This happened with a Nose hook and student
pilot. I believe that the most
important factor in this disscussion is the lack of experience not
wether or not it is a nose or belly
or cg hook!"
- - - - -

As Bill Dean wrote much earlier in this thread, the BGA recommendations
after a series of these accidents and the Chris Rollings etc. tests
included:

"The operators' attention is drawn to the following factors which may
cumulatively contribute to a hazardous situation:

(a) Low experience of glider and/or tug pilot
(b) Gliders fitted with C of G hook only
(c) Glider's C of G towards the aft limit
(d) Turbulent air in the take-off area
(e) Rough ground in the take-off area
(f) Significant cross-wind component."

Note, 6 factors, in addition to rope length, not just the hook position
issue. At the same time, there was a poster produced which no-one now
seems to have a copy of. My recollection of it was that it listed these
6 factors and said that if more than one or two were present, it would
be wise not to undertake such a flight. To think that there is just one
factor and any of the others can be any which way is asking for trouble.

I have no idea why people are still arguing about it. We have almost
eliminated tug upset accidents in the UK since this and the "Low
High-tow" standardisation, yet some people think the BGA should have
done nothing except change rope lengths and maybe not even that, some
people think it can't happen to them, and some people think we did no
more than mandate nose hooks when it was not in fact mandated in the UK,
just encouraged where possible.

Seems to me that if people want to go on risking lives in other
countries, feel free - and tell the tug pilots' families you don't mind
being sued, having read about and ignored the entire series of
recommendations that seem to have largely eliminated this type of
fatality where it was researched.

Chris N.

"Z Goudie" wrote in message
...
Come on people, is the gliding world turning into a
nannie state?

As a glider pilot for some 40 odd (some very odd) years
and a tug pilot for 30 I can't believe some of this
drivel.

Launching of any description on any hook is not a problem
if the gowk at the back has had it properly drummed
into him to keep his hand on the release and thus be
able to throw the launch away instantly in the event
of a dropped wing or the tug disappearing from sight.

Agreed.

Bill Daniels

"Chris Nicholas" wrote...
"The operators' attention is drawn to the following factors which may
cumulatively contribute to a hazardous situation:

(a) Low experience of glider and/or tug pilot
(b) Gliders fitted with C of G hook only
(c) Glider's C of G towards the aft limit
(d) Turbulent air in the take-off area
(e) Rough ground in the take-off area
(f) Significant cross-wind component."

snip...
Seems to me that if people want to go on risking lives in other
countries, feel free - and tell the tug pilots' families you don't mind
being sued, having read about and ignored the entire series of
recommendations that seem to have largely eliminated this type of
fatality where it was researched.

The length of this thread, and the bulk of the argument resulted from the
fact that some took one of the 6 points listed aboved (b) and made the
unequivocal statements to the effect that aerotowing with a CG hook was
dangerous and bordered on criminal. This is not, apparently, what the BGA
has said, it is simply the opinion of certain individuals.

I didn't notice anyone arguing that nose hooks aren't better for aerotowing,
the issue is whether CG hooks are sufficiently less safe than nose hooks
that we should flat out refuse to aerotow with them. For obvious reasons,
it is difficult to provide evidence based on actual accident data which
would justify the latter. We have, however, had at least 3 towplane upsets
here in the US that involved gliders with nosehooks, so eliminating CG hooks
most clearly will not eliminate towplane upsets and associated fatalities.

Here in the US, anyway, if we were to take a chunk of money to improve the
safety of aerotows, I'd say there is reasonable evidence that retrofitting a
bunch of gliders with nose hooks is not the most cost effective approach.
I' guess we would likely save a lot more tow (and glider) pilot lives, for
less money, if we (a) developed a safer alternative to the Schweizer tow
plane hook, (b) retrofitted swing open glider canopies with a spring loaded
positive latch, and (c) retrofitted gliders that have divebrakes that open
when unlocked, with a Piggot-style hook arrangement.

Marc

Would anyone be willing to translate and paraphrase this article? I
would be epecially appreciative of our effort.

Chris O'Callaghan

Andreas,

thanks for the link. I'll do my best to get it translated. We've some
willing German speakers at the club, but it's unlikely I'll see any of
them before March!

Cheers

Andreas Maurer wrote in message . ..
On 8 Jan 2004 11:02:45 GMT, "Ian Johnston"
wrote:

My Pirat does the rotation all by itself on a winch launch, regardless
of pilot input.

Does this mean that if you push the stick forward, you are unable to
stop the rotation (in other words - the pilot in a Pirat has no pitch
control during the winch launch)?

In my experience, yes, but only during the initial rotation, and it
only happens at a reasonable speed. In the climb it's fine. And a very
gentle initial acceleration avoids the earlier problems, mostly.

Ian

"W.J. \(Bill\) Dean \(U.K.\)." wrote in message ...
W.J. (Bill) Dean (U.K.).
Remove "ic" to reply.


"Ian Johnston" wrote in message
news:cCUlhtvFIYkV-pn2-bKdumM0BMIOs@localhost...


On Thu, 8 Jan 2004 10:18:37 UTC, "W.J. \(Bill\) Dean \(U.K.\)."
wrote:

A pilot might aerotow on an aft hook when a forward hook is fitted if:

a/ The forward hook is unserviceable,


That would be ruled out by my " ... is available"


NO!

If the forward hook is unserviceable, then the glider is unserviceable for
aerotow.

I'm not quite sure why you're contracdicting me when I'm agreeing with
you. The question I asked was: "Under what circumstances would one tow
with a CG hook when a nose hook was available?" An unserviceable hook
ain't available!

Mind you, if it was a type which was often aerotowed on a belly hook,
and if the pilot knew what s/he was in for, and had suitable
experience, then it wouldn't worry me greatly.

Would you aerotow your Pirat on the aft hook if the forward hook is
unserviceable?

No. For reasons I have outlined. And that's because of particular
properties of the Pirat belly hook.

Would you winch launch a K21 on the forward hook (with no back release!) if
the aft hook is unserviceable? Would you do it if you could make the
forward hook back release? Would you wire launch any glider on the forward
hook (unless the C. of A. papers specifically allowed it) ?.

I sense a little hostility here! I would not winch launch a K21 on the
nose hook, mainly because I am too busy beating my wife. And I haven't
winched the Pirat on the nose hook either, partly because I can't see
the point and partly because it doesn't have a back release.

The glider has two hooks for a reason. If an apparently otherwise
identical glider has only one hook, that is a bad reason for assuming that
you can treat your glider hooks as interchangeable.

All assumptions are unreasonable. Deductions are fine!

And that would be sheer stupidity - the cause, I reckon, of 90% of all
gliding accidents.

What seems stupidity to you may be a habit formed at a site where this has
become normal behaviour over the years.

Indeed. Group stupidity appears in the blood-and-gore section of S&G
just as much as individual stupidity!

Have you never visited a site, or noticed a particular pilot or syndicate,
and said to yourself "there is an accident waiting to happen" ? Accident
investigators look for this, as well as the particular factors directly
leading to an accident.

True. There is one major gliding club in the UK midlands (it's not the
Midlands Gliding Club!) at which I will not fly because their attitude
to safety, on the one occasion I visited, was so sloppy as to be
almost unbelievable. And that was a couple of weeks after they'd
killed someone on the winch...

Ian

PS On rereading, let me make it clear: I am in favour of gliders
having nose hooks and I am in favour of using them for aerotows!

On Thu, 8 Jan 2004 10:57:33 -0800, "Marc Ramsey"
wrote:


"Chris Nicholas" wrote...
"The operators' attention is drawn to the following factors which may
cumulatively contribute to a hazardous situation:

(a) Low experience of glider and/or tug pilot
(b) Gliders fitted with C of G hook only
(c) Glider's C of G towards the aft limit
(d) Turbulent air in the take-off area
(e) Rough ground in the take-off area
(f) Significant cross-wind component."

snip...
Seems to me that if people want to go on risking lives in other
countries, feel free - and tell the tug pilots' families you don't mind
being sued, having read about and ignored the entire series of
recommendations that seem to have largely eliminated this type of
fatality where it was researched.

The length of this thread, and the bulk of the argument resulted from the
fact that some took one of the 6 points listed aboved (b) and made the
unequivocal statements to the effect that aerotowing with a CG hook was
dangerous and bordered on criminal. This is not, apparently, what the BGA
has said, it is simply the opinion of certain individuals.

I didn't notice anyone arguing that nose hooks aren't better for aerotowing,
the issue is whether CG hooks are sufficiently less safe than nose hooks
that we should flat out refuse to aerotow with them. For obvious reasons,
it is difficult to provide evidence based on actual accident data which
would justify the latter. We have, however, had at least 3 towplane upsets
here in the US that involved gliders with nosehooks, so eliminating CG hooks
most clearly will not eliminate towplane upsets and associated fatalities.

Here in the US, anyway, if we were to take a chunk of money to improve the
safety of aerotows, I'd say there is reasonable evidence that retrofitting a
bunch of gliders with nose hooks is not the most cost effective approach.
I' guess we would likely save a lot more tow (and glider) pilot lives, for
less money, if we (a) developed a safer alternative to the Schweizer tow
plane hook, (b) retrofitted swing open glider canopies with a spring loaded
positive latch, and (c) retrofitted gliders that have divebrakes that open
when unlocked, with a Piggot-style hook arrangement.

Marc


Spot on Marc.
a) Is already available.
b) Is problematical - there is a lot of friction in a Schempp canopy
latch which if the closing spring was powerful enough would likely
make the canopy difficult to open.
Whatever happened to pre takeoff checks?
c) Is a good idea and incredibly cheap to implement so worth doing
even if the benefit is slight.

It is the easiest thing in the world to spend someone else's money on
safety improvements. The aim must always be to spend it in the manner
where you get the most improvement for your dollar. Otherwise we are
open to uncontrolled cost increases for "improved safety" mostly based
on little more than conjecture.

Mike Borgelt

Now there's a piece of real valuable insight, Z. And we all know what would
happen if a frog had wings.

At least give us poor tuggies the ability to survive the (eventually)
inevitable tow with a "gowk" who has not received a proper "drumming".

A proper Tost hook, or at least an inverted Schweizer hook;
no CG hook aerotows when nose hook is available, and then only with glider
guiders of proven competence, is not too much to ask!

May we all continue to glide safely!



Jack
--------------

On 2004/01/08 09:36, in article ,
"Z Goudie" wrote:

Come on people, is the gliding world turning into a
nannie state?

As a glider pilot for some 40 odd (some very odd) years
and a tug pilot for 30 I can't believe some of this
drivel.

Launching of any description on any hook is not a problem
if the gowk at the back has had it properly drummed
into him to keep his hand on the release and thus be
able to throw the launch away instantly in the event
of a dropped wing or the tug disappearing from sight.

Mike Borgelt wrote:

The LBA/BGA/GFA/insert your civil aviation bureaucracy name here
bureaucracy get to feel good because they have "improved" safety and
can boast about this, most of the glider pilots don't care one way or
the other as they are unaffected and tow pilots are at just as much
risk as before as the fleet replacement only occurs slowly. Great!

Even if you completely discount the risk of getting out of position,
there is still a benefit to the glider pilot: the first 100' or so until
the glider has good control is significantly better with nose hook. I've
seen ground accidents that would not have occurred (including mine) with
a nose hook. If you normally aerotow, I think it's cheap insurance to
get one with your new glider. It might be almost as good a value as a
retrofit, but because retrofit costs can vary so much, I can't be
dogmatic about it. It was a good value to retrofit my ASW 20 C.


Requiring longer ropes would have been cheaper and would give
immediate benefits but here we are still thinking 150 feet is
adequate. Wonderful.

A longer rope won't aid the pilot in the first 100', when these ground
accidents usually develop.

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Eric Greenwell
Washington State
USA