Nimbus 4DT accident 31 July 2000 in Spain.

Deploy the "Other Spoilers"?
As a pilot of an 18m Ventus, I don't think my high-speed-dive-recovery
problems are nearly as bad as those of a pilot of a 25m Nimbus, but
nevertheless, these problems still feel uncomfortably close to home.
In light of the well-discussed problems of deploying spoilers to control
airspeed while trying to pull out of a steep dive, how about dropping the
landing gear?
On the Ventus, the main wheel swings forward as it is lowered, so I can
imagine that at airspeeds approaching or exceeding Vne, it might not be
possible to get the gear down-and-locked, but could even a partially
deployed wheel and the open wheel bay add enough drag to correct an
otherwise unrecoverable situation?
Even more radically, how about jettisoning the canopy as a speed control
measure?
Or both?
What do the experts on this newsgroup think?

"Don Johnstone" wrote in
message ...
If Stans analysis is right, and I can see no obvious
flaw, once the spiral dive/spin situation is met then
the chances of a sucessful recovery are slim. The 4DT
would not be unique in this. Perhaps a tail parachute
is an essential item of equipment.

Food for thought


At 15:18 30 June 2005, Bill wrote:

Stan Hall presented his analysis of the Nimbus-4DB
accident in Minden,
NV, 1999. Stan's analysis is scary, to say the least.

The article, Probing for the Smoking Gun, was reprinted
in the Soaring
Association of Canada's free flight, 2/04. Go to the
link below. Click
on free flight on the side bar. Go to free flight back
issues - 2004 -
issue 2. Down load the PDF file.

http://www.sac.ca/

Bill Feldbaumer 09

The article was very interesting. The idea of aileron
stiffness at high bending was thought-provoking.

'Abandoning ailerons for a more effective way of starting
and stopping roll...' Perhaps a reference to
full span spoilers for roll?

'the smoking gun was the aircraft's incredibly high
performance.' This is consistent with, but not a proof
of, the things I've written before about USA fatalities
and L/D.
Of course, this was however NOT a ridge flying accident.

The article didn't mention the possibility that the
other
pilot may have popped the airbrakes/two pilots on the
controls working at odds with each other. Of course
there
is absolutely no way to confirm or deny this.

Lastly, I liked the article's end, and the idea of
big bold red letters in the AFM. It also occered to
me that some of the
'seconds to accelerate from stall speed to ...' and
a lot
of the ideas we have, and how we practice spins and
spirals, is in STILL AIR. I generally don't go up
in huge
thermals/turbulence to practice spins, specifically
so I don't exceed Va and gust loads and 1/3 deflection,
etc.

Does a spin turn into a spiral on it's own sometimes
in turbulent air? Can AOAs be changed by turbulence
alone,
with no movement of controls? Oh, yes.

Start throwing in severe turbulence (which we love,
when it
suits us) and I think we are closer to the 'naked edge
of safety'
than is obvious.

The 2-32 accident in Hawaii was anectdotally in 'the
toilet bowl' there in turbulent air, too. Shear 10/20/30
knots in a few
seconds and 1/4 mile vertically or horizontally, and
our
still air analysis can't be done with a pristine slide-rule...
At 17:12 30 June 2005, Don Johnstone wrote:
If Stans analysis is right, and I can see no obvious
flaw, once the spiral dive/spin situation is met then
the chances of a sucessful recovery are slim. The 4DT
would not be unique in this. Perhaps a tail parachute
is an essential item of equipment.

Food for thought


At 15:18 30 June 2005, Bill wrote:

Stan Hall presented his analysis of the Nimbus-4DB
accident in Minden,
NV, 1999. Stan's analysis is scary, to say the least.

The article, Probing for the Smoking Gun, was reprinted
in the Soaring
Association of Canada's free flight, 2/04. Go to the
link below. Click
on free flight on the side bar. Go to free flight back
issues - 2004 -
issue 2. Down load the PDF file.

http://www.sac.ca/

Bill Feldbaumer 09






Mark J. Boyd

This article makes you want to install a ballistic recovery chute in this
class of glider to handle a worst case scenario.

Mike Schumann

"M B" wrote in message
...
The article was very interesting. The idea of aileron
stiffness at high bending was thought-provoking.

'Abandoning ailerons for a more effective way of starting
and stopping roll...' Perhaps a reference to
full span spoilers for roll?

'the smoking gun was the aircraft's incredibly high
performance.' This is consistent with, but not a proof
of, the things I've written before about USA fatalities
and L/D.
Of course, this was however NOT a ridge flying accident.

The article didn't mention the possibility that the
other
pilot may have popped the airbrakes/two pilots on the
controls working at odds with each other. Of course
there
is absolutely no way to confirm or deny this.

Lastly, I liked the article's end, and the idea of
big bold red letters in the AFM. It also occered to
me that some of the
'seconds to accelerate from stall speed to ...' and
a lot
of the ideas we have, and how we practice spins and
spirals, is in STILL AIR. I generally don't go up
in huge
thermals/turbulence to practice spins, specifically
so I don't exceed Va and gust loads and 1/3 deflection,
etc.

Does a spin turn into a spiral on it's own sometimes
in turbulent air? Can AOAs be changed by turbulence
alone,
with no movement of controls? Oh, yes.

Start throwing in severe turbulence (which we love,
when it
suits us) and I think we are closer to the 'naked edge
of safety'
than is obvious.

The 2-32 accident in Hawaii was anectdotally in 'the
toilet bowl' there in turbulent air, too. Shear 10/20/30
knots in a few
seconds and 1/4 mile vertically or horizontally, and
our
still air analysis can't be done with a pristine slide-rule...
At 17:12 30 June 2005, Don Johnstone wrote:
If Stans analysis is right, and I can see no obvious
flaw, once the spiral dive/spin situation is met then
the chances of a sucessful recovery are slim. The 4DT
would not be unique in this. Perhaps a tail parachute
is an essential item of equipment.

Food for thought


At 15:18 30 June 2005, Bill wrote:

Stan Hall presented his analysis of the Nimbus-4DB
accident in Minden,
NV, 1999. Stan's analysis is scary, to say the least.

The article, Probing for the Smoking Gun, was reprinted
in the Soaring
Association of Canada's free flight, 2/04. Go to the
link below. Click
on free flight on the side bar. Go to free flight back
issues - 2004 -
issue 2. Down load the PDF file.

http://www.sac.ca/

Bill Feldbaumer 09






Mark J. Boyd

At 13:30 01 July 2005, T O D D P A T T I S T wrote:
'Mike Schumann' wrote:

From what I have seen, I doubt that winch launches
require more people than
air tow. One of the biggest problems we have with
air tow is finding tow
pilots who have the necessary hours in type to meet
insurance requirements.

I agree, that is a problem.

I suspect that it would be much easier for your typical
club to train and
line up qualified winch operators than finding tow
pilots.

For a club, particularly one with some members already
trained and comfortable with winch launches, you are
probably right, but at least with aerotowing, you get
pilots
volunteering just because they like to fly, but don't
want
to pay for it. Is running the winch considered to
be a
desirable job similar to flying the tug?

It is for me. Escaping down the winch end is a definite
bonus with the nonsense that can occur at the flying
end. Heater and wall to wall Queen/Dire Straits. Wonderful
way to spend time when soaring is not possible.

T o d d P a t t i s t - 'WH' Ventus C
(Remove DONTSPAMME from address to email reply.)

At 19:42 03 July 2005, Ian Johnston wrote:

I reckon it takes at least ten launches, particularly
on a windy day,
for a driver to get his/her hand in, and a further
ten for them to be
polished.

What?? 20 Launches to get to a 'polished' standard!
(on each day, is this?) Jesus, you have cr*p winch
drivers, or cr*p winch instructors! So this is what
you reckon Ian? Are you winch driver?

So if you use a couple of drivers a day (am/pm split,
maybe)
I'm sure standards will be quite acceptable.
It's places - and I have been there - where driving
the winch is seen
as an unpopular chore, so people reluctantly do two
or three and then
hand over, where standards really start to slip.

Good winch training, makes good winch drivers, just
like flying training, if some winch driver does 10
bad launches, 'to get his/her eye in', I think he would
be on re-training or very poor! (after buying a round
of drinks for everyone he gave a cr*p launch to).

Even our less experienced winch drivers, generally
only take two launches to get their eye in, after good
feedback from the pilots.

I will send you one of our 70+ year old winch drivers
to you (before they get stopped by insurance companies,
EU directives, lack of binoculars, party poopers........)
I'm sure you need them.

Hopefully you have exaggerated the number of launches.
lol

Dave

On Sun, 3 Jul 2005 22:14:27 UTC, Dave Ruttle
wrote:

At 19:42 03 July 2005, Ian Johnston wrote:

I reckon it takes at least ten launches, particularly
on a windy day,
for a driver to get his/her hand in, and a further
ten for them to be
polished.

What?? 20 Launches to get to a 'polished' standard!
(on each day, is this?) Jesus, you have cr*p winch
drivers, or cr*p winch instructors! So this is what
you reckon Ian? Are you winch driver?

I'm a winch driver and a winch instructor. And yes, if it's a windy
day, and you're launching a mixture glass and wood, single and two
seater, I stand completely by what I wrote. Ten or so launches to do
it reasonably well, twenty to be giving bang on, optimum speed,
perfect height launches every time.

Of course it's possible to do some sort of launch without taking much
care over it. If you don't fly at a club which takes winch driving
seriously you probably don't know how good it can be.

Good winch training, makes good winch drivers, just
like flying training, if some winch driver does 10
bad launches, 'to get his/her eye in', I think he would
be on re-training or very poor! (after buying a round
of drinks for everyone he gave a cr*p launch to).

I didn't write "crap launch" and I didn't mean "crap" launch.

And just as with pilots, training is only the beginning. It's
practice, practice, practice after that. I'm certainly not claiming
that it's rocket science, but it is something that can be done
adequately or much better.

In case you were wondering, I am a complete sod to winch drivers when
I'm flying. I pull off for overspeeds without a second's hesitation
(many/most pilots just accept them: they shouldn't) and I don't take
underspeeds either. I invariably refuse to pay for aborted launches,
and when one winch driver told me I should have pulled back (ten feet
in the air) to accelerate I formally complained to his club's safety
officer about his competence and attitude.

Even our less experienced winch drivers, generally
only take two launches to get their eye in, after good
feedback from the pilots.

If you are happy with those standards, fine.

Ian

Is it my understanding that the winch drivers
at these operations make NOTHING? No money at all?

Hmmm...in the USA, even the clubs where the
aerotow pilots do it for free, there is still SOME
benefit. Either they are building time, or they get
to
rent the towplane for cheap on non-soaring days,
or they get free training to be towpilots (which they
can then use to prove experience at a for-profit operation).

I would think that at least SOME of the winch operations
pay SOMETHING. Even $1 or $2 a launch...

If not, I'm not surprised it is unpopular duty. Do
they
get a free BBQ dinner or something at least?

At 19:00 03 July 2005, Malcolm Austin wrote:
Your comments fit in my own experience at a fairly
small club I've spent
most of my time at.

With around 60 members there are only about 8 to 10
who are 'cleared' for
the winch.
Instructors do not winch unless it's a special occasion
or a really quiet
day. There really
isn't enough of them to waste on the winch anyway!

Putting someone on the winch for a full day has/is
resulting in loosing
these people to
other activities (i.e. not gliding). The other problem
with such a low
number of trained
people is that the winch duty comes around every 4
weeks. And also what
happens is
that if you turn up to fly and the duty man isn't there,
you end up on the
winch all day
again. If you've gone to fly and end up working, it's
extremely
demotivating.

I agree with your thoughts that a winch man is intimately
involved in every
launch, its a very
responsible job and takes quite a bit of skill to complete
correctly. As to
the point that
some individuals don't make good winchmen, absolutely
right every time!
These
people seem uncordinated and unaware of what's happening
around them, and
they seem
to fly that way. Almost an accident waiting to happen
I guess.

Cheers, Malcolm..

'Bruce' wrote in message
...
Ian Johnston wrote:
On Sat, 2 Jul 2005 10:39:35 UTC, Bruce wrote:

: We have a better rule - no solo in glider before
solo on winch...

It's not a bad idea, but it can and does (in my experience)
lead to clubs
with large numbers of not-very-good winch drivers.
I'd much rather be
launched by someone who has done dozens or hundreds
of launches than
someone who does a few every few weeks to satisfy
club rules.

Ian, winch-but-not-any-other-sort-of-instructor
Ian

We average around 26-35 launches a day. With a small
club and the
instructors doing less winching (although everyone
including the CFI
drives winch) this means that our students, and solo
pilots get to do
plenty of winch driving.

Instructors can expect to spend some time on the winch
- maybe 5 or 10
launches, once every quarter. Although we have one
who volunteers just
about ever time he is there - he just loves playing
tunes with that V8...
The others will share the launching, on average doing
around 8 launches on
any given day. It is not onerous, everyone shares
the work and pitches in,
and the experience on the winch means the low time
pilots have a better
understanding of what is going on. There are days
when one of the more
experienced types installs him/herself in the winch
and makes the day go
smoothly, and the inexperienced types get a benchmark
to aim for. But if
we did that every week we would soon lose the 'really
good' winch drivers.
Spending a few hours seeing how well you can get the
winch to perform,
every now and then is one thing,(and can be very rewarding)
but we all go
to the airfield to fly...

Our experience is that there are a few individuals
who never make
satisfactory winch drivers. With few exceptions they
also struggle with
the flying part. You learn a lot observing someone
on the winch. And
driving the winch in all the different conditions
accelerates learning, he
may not be flying, but the winch driver is intimately
involved in every
launch.

--
Bruce Greeff
Std Cirrus #57
I'm no-T at the address above.



Mark J. Boyd

On Sun, 3 Jul 2005 22:35:33 UTC, M B
wrote:

Is it my understanding that the winch drivers
at these operations make NOTHING? No money at all?

The club at which I am a winch instructor allows the duty winch driver
to fly (once) in a club glider whenever s/he wishes during their
stint, bypassing the list. That flight is free.

Ian

M B wrote:
Is it my understanding that the winch drivers
at these operations make NOTHING? No money at all?

Hmmm...in the USA, even the clubs where the
aerotow pilots do it for free, there is still SOME
benefit. Either they are building time, or they get
to
rent the towplane for cheap on non-soaring days,
or they get free training to be towpilots (which they
can then use to prove experience at a for-profit operation).

I would think that at least SOME of the winch operations
pay SOMETHING. Even $1 or $2 a launch...

If not, I'm not surprised it is unpopular duty. Do
they
get a free BBQ dinner or something at least?



We don't pay for instruction, tractor driving, making meals, fixing
gliders, mowing the runways, retrieving gliders etc - why should we pay
the winch driver. All these duties are part of the smooth running of
the club and if somebody does not want to do his part - then he will
not fit into the club atmosphere.

All members are expected to go solo on the winch just after going solo
on the glider. The result is that there are plenty of experienced winch
drivers so nobody ends up spending the whole day on the winch. We
prefer to train on the winch only after the student has gone solo on
the glider because we wish the winch driver to have a fair knowledge of
what is going through the pilot's mind at each stage of the launch.

We pay the equivalent of US$3.33 per launch - so there is no spare
money to pay somebody to drive the winch without putting the costs up
for everybody. The result is the best glider fleet in Africa and
probably the cheapest rates in the world. Where else can you fly an ASW
20 at US$0.15/minute.

Clinton
LAK 12
www.ggc.co.za

What a sorry bunch.

Our winch drivers are rewarded with a number of things no amount of money can buy.

1] the gratitude of their peers
2] camaraderie
3] an inexhaustible store of tall tales to tell - legendary cable breaks
4] personal growth, and the pleasure of doing a simple job so well nobody
notices (funny how everyone notices a less than perfect one)
5] the knowledge that, having contributed fairly, the rest of the club will do
the same so that your flying remains affordable and fun
6] time for introspection away from the crowd the other end
7] Last but not least a lot of fun

On the subject of money - I just can't think how you could successfully pay the
two (financial) extremes at our club. The artisan who drives the winch for the
sheer fun of the V8s roar, or the big company CEO who does it because he is an
instructor and it is part of the club scene. I suspect both would be insulted if
you offered them money...



M B wrote:
Is it my understanding that the winch drivers
at these operations make NOTHING? No money at all?

Hmmm...in the USA, even the clubs where the
aerotow pilots do it for free, there is still SOME
benefit. Either they are building time, or they get
to
rent the towplane for cheap on non-soaring days,
or they get free training to be towpilots (which they
can then use to prove experience at a for-profit operation).

I would think that at least SOME of the winch operations
pay SOMETHING. Even $1 or $2 a launch...

If not, I'm not surprised it is unpopular duty. Do
they
get a free BBQ dinner or something at least?

At 19:00 03 July 2005, Malcolm Austin wrote:

Your comments fit in my own experience at a fairly
small club I've spent
most of my time at.

With around 60 members there are only about 8 to 10
who are 'cleared' for
the winch.
Instructors do not winch unless it's a special occasion
or a really quiet
day. There really
isn't enough of them to waste on the winch anyway!

Putting someone on the winch for a full day has/is
resulting in loosing
these people to
other activities (i.e. not gliding). The other problem
with such a low
number of trained
people is that the winch duty comes around every 4
weeks. And also what
happens is
that if you turn up to fly and the duty man isn't there,
you end up on the
winch all day
again. If you've gone to fly and end up working, it's
extremely
demotivating.

I agree with your thoughts that a winch man is intimately
involved in every
launch, its a very
responsible job and takes quite a bit of skill to complete
correctly. As to
the point that
some individuals don't make good winchmen, absolutely
right every time!
These
people seem uncordinated and unaware of what's happening
around them, and
they seem
to fly that way. Almost an accident waiting to happen
I guess.

Cheers, Malcolm..

'Bruce' wrote in message
...

Ian Johnston wrote:

On Sat, 2 Jul 2005 10:39:35 UTC, Bruce wrote:

: We have a better rule - no solo in glider before
solo on winch...

It's not a bad idea, but it can and does (in my experience)
lead to clubs
with large numbers of not-very-good winch drivers.
I'd much rather be
launched by someone who has done dozens or hundreds
of launches than
someone who does a few every few weeks to satisfy
club rules.

Ian, winch-but-not-any-other-sort-of-instructor

Ian

We average around 26-35 launches a day. With a small
club and the
instructors doing less winching (although everyone
including the CFI
drives winch) this means that our students, and solo
pilots get to do
plenty of winch driving.

Instructors can expect to spend some time on the winch
- maybe 5 or 10
launches, once every quarter. Although we have one
who volunteers just
about ever time he is there - he just loves playing
tunes with that V8...
The others will share the launching, on average doing
around 8 launches on
any given day. It is not onerous, everyone shares
the work and pitches in,
and the experience on the winch means the low time
pilots have a better
understanding of what is going on. There are days
when one of the more
experienced types installs him/herself in the winch
and makes the day go
smoothly, and the inexperienced types get a benchmark
to aim for. But if
we did that every week we would soon lose the 'really
good' winch drivers.
Spending a few hours seeing how well you can get the
winch to perform,
every now and then is one thing,(and can be very rewarding)
but we all go
to the airfield to fly...

Our experience is that there are a few individuals
who never make
satisfactory winch drivers. With few exceptions they
also struggle with
the flying part. You learn a lot observing someone
on the winch. And
driving the winch in all the different conditions
accelerates learning, he
may not be flying, but the winch driver is intimately
involved in every
launch.

--
Bruce Greeff
Std Cirrus #57
I'm no-T at the address above.



Mark J. Boyd




--
Bruce Greeff
Std Cirrus #57
I'm no-T at the address above.