CG hook on aero tows??

In article ,
Ian Strachan wrote:
In article 3ffee053$1@darkstar, Mark James Boyd
writes

snip

If anyone decides to modify their experimental glider to
be towed tail first on a tailhook, I guess we have two
volunteers to be the tow pilots...

The main question is, in how many seconds would it be being towed
tail-first ......

Another question would be insurance, but we are in "reductio ad
absurdum" land, here, aren't we?

--
Ian Strachan
Lasham, UK

Ian,

Exactly right. So if we can all agree that "given the
appropriate level of experience and skill, a pilot can
fly any flyable aircraft in any conditions," we can avoid this
obvious truth and focus on the relative risks and
costs (including the cost of acquiring training and
experience).

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.

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.

"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

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

CG hooks on tow do not create a problem for competent pilots. It is only
necessary to fly the towed glider, as in close formation flying, without
depending on the tow hook to do a lot of the work for you. Of course, very
short tow ropes can make any tow difficult. Both my own glider, a Phoebus
A-1, and the DG-101 I frequently fly in my club, have only CG hooks. With
reasonable tow-rope length I have never found CG hooks to present any
problems. But, do keep the trim full down on take-off.

Ed

"E. A. Grens" wrote in message ...
CG hooks on tow do not create a problem for competent pilots.

That's true, by definition: "A competent pilot is one for whom CG
hooks on tow do not cause problems." The trouble is - as my club has
found out - is that many pilots don't know whether or not they are
competent in this regard. We do some very wild towing in primary
rotor: even with a nose hook the tow can be a testing experience!

Ian

Chris Nicholas wrote in message ...

Chris you listed the following 6


"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."

Then stated, almost as an aside,


We have almost
eliminated tug upset accidents in the UK since this and the "Low
High-tow" standardisation,

I suspect that condition 7 may be more significant in reducing tug
upsets than any of the 6 in the primary list.

As a US instructor I have flown with many pilots that received their
initial training from other instructors. I have often been surprised
at the tow position taken by such pilots. I usually urge them to keep
lowering the tow position until they feel the wake, then to move just
high enough that the wake is not a factor. That tow position may be
10 or 15 ft lower than that initially used.

A pilot flying a high high tow has less time to react to a potential
upset than one flying the UK recommended low high tow. The fact that
US pilots seem to be trained to use high high tow may explain why tug
upsets continue to happen even when a nose or forward hook is used.


Andy (GY)

"Andy Durbin" wrote in message
om...
Chris Nicholas wrote in message
...

Chris you listed the following 6


"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."

Then stated, almost as an aside,


We have almost
eliminated tug upset accidents in the UK since this and the "Low
High-tow" standardisation,

I suspect that condition 7 may be more significant in reducing tug
upsets than any of the 6 in the primary list.

As a US instructor I have flown with many pilots that received their
initial training from other instructors. I have often been surprised
at the tow position taken by such pilots. I usually urge them to keep
lowering the tow position until they feel the wake, then to move just
high enough that the wake is not a factor. That tow position may be
10 or 15 ft lower than that initially used.

A pilot flying a high high tow has less time to react to a potential
upset than one flying the UK recommended low high tow. The fact that
US pilots seem to be trained to use high high tow may explain why tug
upsets continue to happen even when a nose or forward hook is used.


Andy (GY)

I've seen the same thing, Andy.

Bill Daniels

Andy Durbin wrote:

As a US instructor I have flown with many pilots that received their
initial training from other instructors. I have often been surprised
at the tow position taken by such pilots. I usually urge them to keep
lowering the tow position until they feel the wake, then to move just
high enough that the wake is not a factor. That tow position may be
10 or 15 ft lower than that initially used.

Where is the towplane, relative to the horizon?

A pilot flying a high high tow has less time to react to a potential
upset than one flying the UK recommended low high tow. The fact that
US pilots seem to be trained to use high high tow may explain why tug
upsets continue to happen even when a nose or forward hook is used.

10 or 15 feet doesn't sound like it would give much extra time, not like
the low tow position Australia uses.

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Eric Greenwell
Washington State
USA