Nimbus 4DT accident 31 July 2000 in Spain.

At 18:12 24 June 2005, Stefan wrote:
Andrew Warbrick wrote:

No, in the accident in Spain which started this thread,
all evidence points to the brakes not being deployed,
at all.

Please read the thread before commenting. HLF, to whom
I was responding,
was explicitely referring to the Minden accident.

Stefan

I'll let that pass with the suggestion that you read
the thread more carefully before flaming people. Enough
said.

Sorry I do not see that finding yourself in a condition
where the nose is well up above the horizon, airspeed
rapidly decaying with the possibility of increase wing
load from hanging cable can be described as 'normal'.
It is a situation we train pilots to recover from but
it also goes against the normal training in that the
reference to the horizon means less than normal.
During the launch the attitude to of the glider to
the relative airflow is within the normal parameters.
As soon as the launch fails, for whatever reason, the
situation becomes abnormal. Lowering the nose to an
attitude relative to the horizon will not result in
instant recovery.
My way of teaching was for the student to carry out
the corrective action and then ask a simple questions.
Do I have the approach attitude? Answer no, correct,
answer yes then 'Do I have the approach airspeed? answer
no, check response to answer yes, if that is still
yes then wait until the answer to the airspeed question
is yes. When the answer to both questions is yes, then
and only then decide on the most appropriate course
of action and implement.

Works for me and I have survived 10000 winch launches

At 12:18 27 June 2005, Stefan wrote:
wrote:

But if you are
flying outside normal flight conditions (IE, aerobatics
or cable break
recoveries),

A cable brake during a winch launch is a perfectly
normal flight
condition, and as such, is regulariliy trained. Maybe
I'm wrong, but it
seems you didn't do many winch launches, did you?

Stefan

Don Johnstone wrote:

Sorry I do not see that finding yourself in a condition
where the nose is well up above the horizon, airspeed
rapidly decaying with the possibility of increase wing
load from hanging cable can be described as 'normal'.

We can argue the meaning of the word normal. For me, everything which
happens from time to time and is no surprize is normal. In winch
launches, cable breakes do occur and are to be expected. So they are
normal me, just a variant. But there's no need to argue about this word.

It is a situation we train pilots to recover from but
it also goes against the normal training in that the
reference to the horizon means less than normal.

Again, what is normal? In flat land, during normal flight, the horizon
is the reference, so that's normal. In mountains, having no natural
horizon but only an imaginary one is normal. And in a winch launch, not
referring to the horizon is normal, at least to me.

Lowering the nose to an
attitude relative to the horizon will not result in
instant recovery.

Exactly, that's why, after a cable break (or after "normal" release, for
that matter), ist "normal" not to refer to the horizon in the same way
as during free flight. Different conditions, different techniques.
Nothing abnormal.

My way of teaching was for the student to carry out

I'm sure you instruct your students correctly. The only thing I jumped
on was the statement that there was something "abnormal" in a winch
launch. Again, different conditions require different techniques, which
means different normalities.

This is the approach I take: Normality depends on cirumstance, so
broaden your view and your repertoire of techniques.

Stefan

I want to thank Don and Stefan and others from Europe and the UK for
stepping in here.

I am fighting a lonely battle to convince my fellow USA pilots that winch
launch is a perfectly normal way to launch gliders and not some invention of
the devil. Those few US pilots who have experienced a winch launch have
most likely done so using horrendously inadequate equipment that would not
have been allowed to operate in your countries. There is no standard
training manuals so each instructor makes up their own. The results range
from hilarious to deadly.

With oil prices exceeding $60US/barrel in the last few days, and aviation
fuel prices heading into uncharted territory, the viability of our 'air tow
only' soaring operations comes into question. If oil prices continue on to
$100/barrel, as the world bank and many investment houses predict, the US
soaring community is in for some rough times if we don't quickly adopt a
more fuel efficient launch method.

To quickly shift to winch launch means that we will have to adopt the best
practices of other countries who have developed winch launch to a high level
of performance and safety.

I appreciate your continued inputs.

Bill Daniels

Bill Daniels wrote:

I am fighting a lonely battle to convince my fellow USA pilots that winch
launch is a perfectly normal way to launch gliders and not some invention of
the devil.

Just three things to consider:

A which launch brings you to a certain altitude above the site. At some
places, this gives you enough options to find a thermal, at other sites,
it does not.

A winch operation doesn't mix well with other traffic. It's doable, if
everybody is willing.

And, most important: If done correctly, a winch launch is safe. But
there is an extremely small margin for errors. I love winch launches,
but they are dead serious, literally.

Stefan

There are certain points during an air tow, where there are also very small
margins for error. I also believe that winch launches have major risk
advantages over air tow, particularly due to the elimination of the tow
plane from the risk equation.

Unfortunately, the field I fly out of is too short for winch launching to be
practical.

Mike Schumann

"Stefan" wrote in message
...
Bill Daniels wrote:

I am fighting a lonely battle to convince my fellow USA pilots that winch
launch is a perfectly normal way to launch gliders and not some invention
of
the devil.

Just three things to consider:

A which launch brings you to a certain altitude above the site. At some
places, this gives you enough options to find a thermal, at other sites,
it does not.

A winch operation doesn't mix well with other traffic. It's doable, if
everybody is willing.

And, most important: If done correctly, a winch launch is safe. But there
is an extremely small margin for errors. I love winch launches, but they
are dead serious, literally.

Stefan

"Bill Daniels" wrote in message
...
I want to thank Don and Stefan and others from Europe and the UK for
stepping in here.

I am fighting a lonely battle to convince my fellow USA pilots that winch
launch is a perfectly normal way to launch gliders and not some invention
of
the devil.

Bill-

I think that you have a chip on your shoulder re winch launches. I have not
seen a single thread that tries to make winch launches sound like they are
an "invention of the devil". Chris' (OC)point is only pertaining to the
aerodynamics unique to the situation that a glider may be in during a winch
launch cable break. He does not seem to be making any a priori assumptions
that anything is dangerous about winch launching. I think that the
discussion re that unique situation is not only interesting but may also
possibly pertain to some other scenarios such as a hard pull and turn into a
thermal, so would like to have a more detailed understanding of it.

Casey Lenox
KC
Phoenix

"Kilo Charlie" wrote in message
news:WS%ve.3566$Qo.977@fed1read01...

"Bill Daniels" wrote in message
...
I want to thank Don and Stefan and others from Europe and the UK for
stepping in here.

I am fighting a lonely battle to convince my fellow USA pilots that
winch
launch is a perfectly normal way to launch gliders and not some
invention
of
the devil.

Bill-

I think that you have a chip on your shoulder re winch launches. I have
not
seen a single thread that tries to make winch launches sound like they are
an "invention of the devil". Chris' (OC)point is only pertaining to the
aerodynamics unique to the situation that a glider may be in during a
winch
launch cable break. He does not seem to be making any a priori
assumptions
that anything is dangerous about winch launching. I think that the
discussion re that unique situation is not only interesting but may also
possibly pertain to some other scenarios such as a hard pull and turn into
a
thermal, so would like to have a more detailed understanding of it.

Casey Lenox
KC
Phoenix

Point accepted. Without thinking, I was responding to opinions expressed
elsewhere and not in this forked thread or elsewhere on RAS. My apology to
anyone thus offended.

The situation envisioned in the beginning of this thread is a very
specialized case where a pilot fails to lower the nose below what appears to
be normal glide attitude after a wire break real or simulated and then
attempts a turn with the wing deeply stalled. That this sometimes results
in a spin departure should surprise no one.

Training for wire breaks starts at a high altitude in free flight. The
zooms, simulated break at 60 knots and pushover are repeated many times
until the student performs them instinctively. If this training is done
correctly, the pilot will have no difficulty lowering the nose the right
amount after a cable break.

Experimenting with this can expose some 'interesting' glider behaviors.
Only those gliders with the largest up elevator authority can stop the nose
from falling through at the normal glide attitude once the fall-through
starts - it requires full aft stick. Arresting the fall through in this
manner with very little forward speed results in a deeply stalled wing with
the angle of attack possibly exceeding 45 degrees. Small asymmetric control
inputs will induce a spin departure that resembles a snap roll about the
vertical axis. I am always surprised by the very low G forces - the glider
seems to 'fall' into the spin with great ease. Once in the spin, normal
recovery methods work fine.

Bill Daniels

Stefan writes
I'm sure you instruct your students correctly. The only thing I jumped
on was the statement that there was something "abnormal" in a winch
launch. Again, different conditions require different techniques, which
means different normalities.

I think we're generally agreed that the conditions during a routine
winch launch are quite "normal" for a glider and its usual modes of
flight.

The assertion, which I agree with, is that the conditions of a launch
failure are abnormal to the normal modes of operation for the glider and
so need peculiar training and discipline to handle safely. But that's no
more a slur against winch launching than the risk of a turbulence
induced incipient spin is a discouragement to thermalling a glider. As
long as you know better than to just "pull back hard on the stick" to
prevent the spin developing and don't try to scratch away from stupidly
low heights it's a non-issue.

This is the approach I take: Normality depends on cirumstance, so
broaden your view and your repertoire of techniques.

However, the obvious extension of such a relativistic view is to argue
that abnormality is a fabrication of perception and that everything can
be termed "normal" within the context of itself. Which may be all well
and good but is catastrophically useless when it comes to defining
anything in terms that are any more than halfway useful.

That said, I can't say I don't agree with you

--
Bill Gribble
http://www.scapegoatsanon.demon.co.uk
- Learn from the mistakes of others.
- You won't live long enough to make all of them yourself.

I know we are getting off the original thread but winch
launching holds no fear for me. On the other hand a
rope break on aero tow is something that I have little
experience of. I do however have a plan and that I
believe is the key.

Understanding the problems, the differences if you
like is what training should all be about. In many
ways with the right training winch launching is safer
than aero tow, if it goes wrong you always have the
airfield to land on.

At 14:24 27 June 2005, wrote:
Glad to inject some humor into your life.

I too am amused by the risks we accept through habituation.
I regularly
take off in tailwinds exceeding 15 knots, with water,
on a runway only
2,600 feet long. I'm used to it, and accept the risk
as a byproduct of
where I fly. Most pilots would consider these practices
insane. As a
result, I stood in a amazement at a US Nationals when
pilots were
showing grave concern over the safety of a launch with
less than 7
miles per hour of tail wind.

For pilots who winch launch regularly, the definition
of normal flight
attitudes is greatly expanded. But I think you'll all
agree that it is
a highly specialized type of flying (even if you are
used to it). Pull
on the stick to go faster. Push to go slower. If the
cable breaks, no
messing around... stick right forward until the nose
is well below the
horizon, then ease it back gently, paying attention
to your airspeed.
Abrupt control motions, significantly reduced g, large
angles of nose
up and nose down, close to the ground, special considerations
regarding
turns... sounds to me like a pretty threatening environment,
sort of
like taking off downwind at gross from a short runway.
Deserves some
special consideration. And occasional reexamination
to prevent the
complacency of experience.

Chuckle.

OC