Cle Elum crash on NTSB

My condolences go out to the family and friends of the pilot.

I have no opinion on the accident as I don't have all the facts and
I'm no expert flight dynamicist.

However, given what I've read on here over the last few days,
some of you, particularly the pilots with no winch launch
experience, will find the BGA winch launch safety initiative
informative:

http://www.gliding.co.uk/bgainfo/saf...hlaunching.htm

At 10:49 28 October 2011, Paul Tribe wrote:
My condolences go out to the family and friends of the pilot.

I have no opinion on the accident as I don't have all the facts and
I'm no expert flight dynamicist.

However, given what I've read on here over the last few days,
some of you, particularly the pilots with no winch launch
experience, will find the BGA winch launch safety initiative
informative:

http://www.gliding.co.uk/bgainfo/saf...hlaunching.htm





Huh? - I definitely only clicked the "post" button once (via
gliderpilot.net).

Let's see what happens to this message.

On Oct 28, 3:49*am, Paul Tribe wrote:
My condolences go out to the family and friends of the pilot.

I have no opinion on the accident as I don't have all the facts and
I'm no expert flight dynamicist.

However, given what I've read on here over the last few days,
some of you, particularly the pilots with no winch launch
experience, will find the BGA winch launch safety initiative
informative:

http://www.gliding.co.uk/bgainfo/saf...hlaunching.htm

Looking at the Google Earth image of the airport, there are fields at
both east and west ends, although the west one is a bit small. At 200
feet altitude with only 600 feet of runway in front of you and,
presumably, an SUV sitting in the middle of it, landing ahead seems to
be ruled out. This leaves landing in the small field ahead or a 180
to land back on the asphalt. Neither option looks really wonderful,
but it's increasingly looking as if the pilot opted for the turn.

Mike

On Oct 28, 5:49*am, Paul Tribe wrote:

However, given what I've read on here over the last few days,
some of you, particularly the pilots with no winch launch
experience, will find the BGA winch launch safety initiative
informative:

http://www.gliding.co.uk/bgainfo/saf...hlaunching.htm

Fascinating Condor (I assume) simulations.

It would appear that "Spin Clip 2" is a candidate for what might have
occured at Cle Elum.

"Spin Clip 1" is a cockpit view which is especially chilling.

Condor seems to be a very nice tool to experience what you don't ever
want to experience, just like the ATP's do in the big simulators.

On Oct 28, 1:55*pm, JohnDeRosa wrote:
On Oct 28, 5:49*am, Paul Tribe wrote:



However, given what I've read on here over the last few days,
some of you, particularly the pilots with no winch launch
experience, will find the BGA winch launch safety initiative
informative:

http://www.gliding.co.uk/bgainfo/saf...hlaunching.htm

Fascinating Condor (I assume) simulations.

It would appear that "Spin Clip 2" is a candidate for what might have
occured at Cle Elum.

"Spin Clip 1" is a cockpit view which is especially chilling.

Condor seems to be a very nice tool to experience what you don't ever
want to experience, just like the ATP's do in the big simulators.

Sailors of the Sky, I think. There's an article someplace about
the Lasham setup. These planes are different from what are in
Condor, also. Still, I'd expect Condor will show the same.

-- Matt

On Oct 28, 2:32*pm, mattm wrote:
On Oct 28, 1:55*pm, JohnDeRosa wrote:



On Oct 28, 5:49*am, Paul Tribe wrote:

However, given what I've read on here over the last few days,
some of you, particularly the pilots with no winch launch
experience, will find the BGA winch launch safety initiative
informative:

http://www.gliding.co.uk/bgainfo/saf...hlaunching.htm

Fascinating Condor (I assume) simulations.

It would appear that "Spin Clip 2" is a candidate for what might have
occured at Cle Elum.

"Spin Clip 1" is a cockpit view which is especially chilling.

Condor seems to be a very nice tool to experience what you don't ever
want to experience, just like the ATP's do in the big simulators.

Sailors of the Sky, I think. *There's an article someplace about
the Lasham setup. *These planes are different from what are in
Condor, also. *Still, I'd expect Condor will show the same.

-- Matt

Condor does an excellent job of simulating stall/spin sequences.
Scary good. The SSF has several videos on their website produced using
Condor. They do a really nice job, I think, of illustrating a bad day
at the gliderport.

http://www.soaringsafety.org/school/badvideo.html

On Fri, 28 Oct 2011 10:55:24 -0700, JohnDeRosa wrote:

It would appear that "Spin Clip 2" is a candidate for what might have
occured at Cle Elum.

"Spin Clip 1" is a cockpit view which is especially chilling.

Both show what we are exhaustively trained against: assuming that you're
OK once you've pushed over to a normal gliding attitude. You're not of
course, because you'll be too slow and, unless you reacted IMMEDIATELY
and got the stick far enough forward for a zero G push-over you'll be
below stall speed, from where any turn will spin immediately.

The rule of thumb[*] is to push over until your dive attitude is as steep
as you were going up and then hold the attitude without attempting to
turn until you've reached the landing approach speed you'd chosen for the
day. Then, and only then you decide whether you've space to land ahead or
whether you need to turn.
[*] unless, of course, its a low break where you'd become a lawn dart if
you used the above technique. Off a winch you'll always have plenty of
specs ahead, so a shallower recovery attitude is OK once you're
combortable above stall speed and anyway you won't need to turn.


Sadly, I think Steve Leonard has probably called this about right. IMO
whether the rope broke or not isn't relevant, but the fact that no
witnesses reported an immediate push-over into a speed recovery attitude
is.


--
martin@ | Martin Gregorie
gregorie. | Essex, UK
org |

Those clips are quite good. We used to do RC aerotow and winching
with scale ships and occasionally it would go bad. If you werent
keeping wings level, the grass could grab a wing tip and look exactly
like that if you didnt pull the release(or the release servo was weak
and failed).

‘There is no much we can do to prevent the "something went terribly
wrong" type of accidents . . . ‘

Sorry, don’t agree, other than such things a wings folding up through
e.g. structural failure, or collision coming from an intruder in the
blind spot.

A properly conducted autotow or winch launch should be conducted such
that ANY eventuality can be handled safely. If there is some
circumstance where that is not possible, it should be foreseeable and
the flight not commenced.

At any stage of the launch, the nose should not be raised to a greater
angle than will allow push over and resumption of normal flying
attitude AND SPEED before needing to commence round out.

I was taught that on autotow, for the first 100 feet, the nose should
be raised very little – the far end of the runway should still be
visible. If power fails or rope breaks, as Martin said, lowering the
nose to the same angle that it was raised (in this case only a small
change of attitude) should therefore be possible.

Higher up, more pitch up is OK because there is more height to
recover. If you can’t, you were too steep too low, and it is the
second kind of accident (‘"someone made a terrible decision" or did
not know what they were doing.’)

That is not to say we don’t have such accidents in the UK. Such UK
accidents have become thankfully more rare But you never HAVE TO have
an accident, if you do it right.

Chris N.
* |

On Oct 29, 12:22*pm, Martin Gregorie
wrote:
Both show what we are exhaustively trained against: assuming that you're
OK once you've pushed over to a normal gliding attitude. You're not of
course, because you'll be too slow and, unless you reacted IMMEDIATELY
and got the stick far enough forward for a zero G push-over you'll be
below stall speed, from where any turn will spin immediately.

The rule of thumb[*] is to push over until your dive attitude is as steep
as you were going up and then hold the attitude without attempting to
turn until you've reached the landing approach speed you'd chosen for the
day. Then, and only then you decide whether you've space to land ahead or
whether you need to turn.

Yes, I agree with this, except there's no need to push. Simply keeping
the stick roughly in the middle will allow the nose to fall through as
the speed drops, without any danger of stalling, and with the wing
operating at an efficient (low drag) angle of attack.

Easing the stick forward enough to get zero G is OK too, but
unnecessary. Negative G is likely to be counterproductive and actually
cause more drag and therefore bleed off more energy than a small
amount of positive G.


[*] unless, of course, its a low break where you'd become a lawn dart if
you used the above technique. Off a winch you'll always have plenty of
specs ahead, so a shallower recovery attitude is OK once you're
comfortable above stall speed and anyway you won't need to turn.

I don't agree.

Assuming you maintain a low drag angle of attack, you'll arrive back
at the release height with the same speed you had on the way up. We
know you made the pull up into the climb from just above ground level,
with an adequate safely margin from stalling, and with lower speed
than you had in the climb. There's no reason at all that you can't
safely pull out of the dive, starting from the cable break height,
even if the cable broke just as you were entering full climb.