Winch Launch Fatality

On Tue, 23 Jun 2009 06:24:24 -0700, bildan wrote:

On Jun 23, 4:34Â*am, John Smith wrote:
ucsdcpc wrote:
The routine we are taught is as follows, all part of the pre-flight
eventualities check before each launch:

1. Â* Â*decide on appropriate approach speed for conditions

2. Â* Â*in the event of a launch failure (not just cable brake) lower
the nose to an appropriate attitude

Wrong, very wrong, very dangerous. The correct sequence is:

1. Push the stick forward and pull the release knob.

2. If possible, land ahead on the remaining runway.

3. If you're too high to land ahead, you have all the time to decide
your further actions. This can be an abbreviated circuit or a downwind
landing, depending on the circumstances.

And yes, doing a 180 too hasty will put you in a situation where you
don't have enough runway to land. So whatever you do, don't panic.
Everything else depends.

Please explain why pulling the release is priority one.

Apart from anything else, your hand should be on the release knob during
the launch, so pulling it a couple of times immediately after pushing
over and just before letting go of it is an obvious move. That is taught
as SOP in my club.

Most likely the
remaining rope and parachute gear has already back released.

..... only if the cable break was down near the winch. If the break was
near the glider you could still have several meters of cable and the
furled drogue dangling trailing from the hook. Its even more likely that
you'll still have the cable attached if the problem is a power fade at
the winch rather than a cable break.


Diverting attention to the release knob when other critical decisions
are pending seems odd when you think about it.

It should be in your hand already, so no attention diversion is needed.

Note to Schweizer operators: Schweizer CG hooks require MUCH more force
to back release than the Tost release so you folks should pull.

There's the other answer: never train somebody to use a technique that is
unsafe on some types of glider. Murphy pretty much mandates they'll
forget to check the cable is gone when they're flying a type where it
matters.


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

On Jun 23, 9:14*am, Martin Gregorie
wrote:
On Tue, 23 Jun 2009 06:24:24 -0700, bildan wrote:
On Jun 23, 4:34*am, John Smith wrote:
ucsdcpc wrote:
The routine we are taught is as follows, all part of the pre-flight
eventualities check before each launch:

1. * *decide on appropriate approach speed for conditions

2. * *in the event of a launch failure (not just cable brake) lower
the nose to an appropriate attitude

Wrong, very wrong, very dangerous. The correct sequence is:

1. Push the stick forward and pull the release knob.

2. If possible, land ahead on the remaining runway.

3. If you're too high to land ahead, you have all the time to decide
your further actions. This can be an abbreviated circuit or a downwind
landing, depending on the circumstances.

And yes, doing a 180 too hasty will put you in a situation where you
don't have enough runway to land. So whatever you do, don't panic.
Everything else depends.

Please explain why pulling the release is priority one.

Apart from anything else, your hand should be on the release knob during
the launch, so pulling it a couple of times immediately after pushing
over and just before letting go of it is an obvious move. That is taught
as SOP in my club.

*Most likely the
remaining rope and parachute gear has already back released.

.... only if the cable break was down near the winch. If the break was
near the glider you could still have several meters of cable and the
furled drogue dangling trailing from the hook. Its even more likely that
you'll still have the cable attached if the problem is a power fade at
the winch rather than a cable break.

Diverting attention to the release knob when other critical decisions
are pending seems odd when you think about it.

It should be in your hand already, so no attention diversion is needed.

Note to Schweizer operators: *Schweizer CG hooks require MUCH more force
to back release than the Tost release so you folks should pull.

There's the other answer: never train somebody to use a technique that is
unsafe on some types of glider. Murphy pretty much mandates they'll
forget to check the cable is gone when they're flying a type where it
matters.

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

I don't think you made your case. I have seen LOTS of wire/rope
breaks, including weak link breaks, and nothing has ever stayed on the
hook - even with Schweizers. But, even if pulling the release is
justified on the assumption that something MIGHT be on the hook AND
assuming that something on the hook would cause damage (It won't kill
you), why a priority?

The reason I brought this up is that I have seen many pilots nearly
bungle a recovery while pulling the release. Even with a hand on the
release, there's no guarantee a pilot will pull it - I've seen pilots
take their hand off the release and pull the spoilers. A launch
failure is no time to be multi-tasking. Screw the release - FLY THE
GLIDER!

I want to see this priority list in order of decreasing urgency:

1. Nose way down NOW!
2. Get a safe airspeed ASAP!
3. Decide on the landing option (Straight or circle.)
4. Execute landing option - concentrate on airspeed and coordination.
5. Pull the release - maybe.

I'm not saying don't pull the release - just don't let it get in the
way of more urgent actions.

bildan wrote:

why a priority?

Pushing the stick and pulling the release is *one* movement. You don't
have to think about it.

The reason I brought this up is that I have seen many pilots nearly
bungle a recovery while pulling the release.

I just don't believe this. But *if* it were true, then those pilots
would *urgently* need a couple of training flights.

Even with a hand on the
release, there's no guarantee a pilot will pull it - I've seen pilots
take their hand off the release and pull the spoilers.

Again, if this were true, then those pilots would urgently need a couple
of training flights.

It seems that there's something very wrong with the pilot training at
your site.

On Jun 23, 10:42*am, John Smith wrote:
bildan wrote:
why a priority?

Pushing the stick and pulling the release is *one* movement. You don't
have to think about it.

You DO have to think about it and doesn't answer the question, "WHY A
PRIORITY?" Just because something is easy doesn't make it a priority.

bildan wrote:

Pushing the stick and pulling the release is *one* movement. You don't
have to think about it.

You DO have to think about it and doesn't answer the question, "WHY A
PRIORITY?" Just because something is easy doesn't make it a priority.

If you have to think about it, then you need more training. Granted, if
you don't have that reflex incorporated, *then* you have to think about it.

On Jun 23, 10:56*am, John Smith wrote:
bildan wrote:
Pushing the stick and pulling the release is *one* movement. You don't
have to think about it.

You DO have to think about it and doesn't answer the question, "WHY A
PRIORITY?" *Just because something is easy doesn't make it a priority..

If you have to think about it, then you need more training. Granted, if
you don't have that reflex incorporated, *then* you have to think about it.

On Tue, 23 Jun 2009 09:00:06 -0700, bildan wrote:

I don't think you made your case. I have seen LOTS of wire/rope breaks,
including weak link breaks, and nothing has ever stayed on the hook -
even with Schweizers.

I've seen several strops dropped when the pilot pulled the release after
a weak link broke. During a practice power fade the cable often stays on
through the push-over, so it follows that this is also likely if the
winch fails for real due to engine trouble or a fuel blockage.

The reason I brought this up is that I have seen many pilots nearly
bungle a recovery while pulling the release. Even with a hand on the
release, there's no guarantee a pilot will pull it - I've seen pilots
take their hand off the release and pull the spoilers. A launch failure
is no time to be multi-tasking.

I've never seen this. An ASW-19 or Pegase on finals with the wheel going
up and down, yes, but brakes opening after a cable break, never.

I want to see this priority list in order of decreasing urgency:

1. Nose way down NOW!
2. Get a safe airspeed ASAP!
3. Decide on the landing option (Straight or circle.)
4. Execute landing option - concentrate on airspeed and coordination.
5. Pull the release - maybe.

Move 5 up to 2 and I'll agree with your sequence. Three reasons:
(a) you're going to wait some seconds for the airspeed to build so
pulling it at this point doesn't delay any other actions.

(b) Your hand is on or very near the release, so just do it.

(c) As I said above, you may be faced with a power fade rather than
a cable break and the cable may still be on. Now, we know that
back-release works for a straight backward pull, but what if
its a high power fade and you get airspeed and turn. Would you
still expect the cable to back release at an angle to the flight
path?


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

1. Nose way down NOW!
2. Get a safe airspeed ASAP!
3. Decide on the landing option (Straight or circle.)
4. Execute landing option - concentrate on airspeed and coordination.
5. Pull the release - maybe.

Move 5 up to 2 and I'll agree with your sequence. Three reasons:
(a) you're going to wait some seconds for the airspeed to build so
* * pulling it at this point doesn't delay any other actions.

(b) Your hand is on or very near the release, so just do it.

(c) As I said above, you may be faced with a power fade rather than
* * a cable break and the cable may still be on. Now, we know that
* * back-release works for a straight backward pull, but what if
* * its a high power fade and you get airspeed and turn. Would you
* * still expect the cable to back release at an angle to the flight
* * path?

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

OK, maybe, as long as it isn't priority 1 - but now you are
introducing a power fade which is a different animal. Power fades are
demonstrated and practiced along with simulated rope breaks just so
pilots know the difference. No one has ever said, "Wow, that's
confusing - how do you tell the difference?"

(C.) However, this one deserves serious consideration. A break is an
obvious "thump" and an upward surge. (Spectra/Dyneema rope generates
a much more obvious thump than steel.)

Assuming the pilot is monitoring airspeed, a power fade means the nose
will coming down and be down to a normal glide attitude and airspeed
as power is totally lost - just as at the top of a normal launch. It
will be managed as if it were a normal launch with a normal release
pull - just at a lower height. Just as with a normal launch, the
winch driver will be alert to the rope not detaching from the glider
and fire the guillotine

For a winch power loss to be confused with a rope break, the power
failure would need to be a rare kind - some sort of explosive loss of
mechanical integrity or seizing up of the winch. But, if the rope is
still attached at the winch, there won't be the upward surge.

On Tue, 23 Jun 2009 14:42:24 -0700, bildan wrote:

OK, maybe, as long as it isn't priority 1 - but now you are introducing
a power fade which is a different animal.

They aren't taught as distinct happenings here - just as winch launch
failures. I agree that they are seldom confused, but the actions to be
taken after a cable break or after a power fade is recognised are the
same: (1) nose down to establish approach speed, (2) make sure cable is
off (3).....

No one has ever said, "Wow, that's confusing - how do you
tell the difference?"

....and I didn't say or imply that anybody confuses the two.

(C.) However, this one deserves serious consideration. A break is an
obvious "thump" and an upward surge. (Spectra/Dyneema rope generates a
much more obvious thump than steel.)

Even when it breaks at the winch end? I wouldn't know - I've not yet
flown on the stuff.

Assuming the pilot is monitoring airspeed, a power fade means the nose
will coming down and be down to a normal glide attitude and airspeed as
power is totally lost - just as at the top of a normal launch.

If its a slow fade the airspeed may easily be lower than approach speed.
IME a slow fade is harder to recognize and deal with than a sudden cut or
a break.


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

(Spectra/Dyneema rope generates a much more obvious thump than steel.)

Even when it breaks at the winch end? I wouldn't know - I've not yet
flown on the stuff.

It doesn't matter where it breaks - the whole rope weighs around 30
Lbs so the feel in the glider is the same.


Assuming the pilot is monitoring airspeed, a power fade means the nose
will coming down and be down to a normal glide attitude and airspeed as
power is totally lost - just as at the top of a normal launch.

If its a slow fade the airspeed may easily be lower than approach speed.
IME a slow fade is harder to recognize and deal with than a sudden cut or
a break.

Not if the pilot is controlling, or just monitoring, the airspeed.
The pilot will lower the nose appropriately to maintain the selected
airspeed. When the power is all gone, the glider will be gliding at
the selected speed - a perfect recovery even if the pilot didn't
recognize the power failure. Lowering the nose is the signal for more
speed so it works in all cases.