Texas Tragedy Info?

http://www.memorialsolutions.com/sit...r=653176Blair#

At 17:15 20 June 2012, Bill D wrote:
On Jun 20, 10:36=A0am, John Cochrane
wrote:
Ramy

Lark manual with scratched in hard to read W&B numbers for that
particu=
lar
ship:http://www.clubplaneadoresbari.com.a...ark_Manual.pdf

Seems to me that a tail dolly heavy enough to put it out of the aft
lim=
it would have to be very heavy.

The manual is interesting. P. 7 says the minimum front seat weight is
183 lbs. it also gives 22-47% mac range
The chart on the last page--an obvious reference if you're taking
light passengers in the front seat -- says 90 lbs in the front seat is
ok
The calculation on the second to last page says 183 in the front seat
is fine at 37%, and 121 in each seat is fine at 39%
Why is the placard 183 lbs then?
Somebody who knows how much a lark dolly weighs could certainly tell
us minimum front seat weight with dolly on given this chart
I surely hope we're not replaying this
onehttp://www.ntsb.gov/aviationque=
ry/brief.aspx?ev_id=3D20001208X06614

John Cochrane

I hope not as well. Both cockpits are well ahead of the aerodynamic
center so I would expect the CG to be well forward with three souls on
board. I don't think the tail dolly had much effect in this accident
as long as it was not unusually heavy. In fact, it may have prevented
a forward-of-limit CG.

That said, the Twin Lark has some 'interesting' trim/pitch stability
behaviors. At higher speeds, even with negative flaps, the glider
becomes progressively nose heavy requiring significant aft stick
pressure to prevent a steeper dive. If re-trimmed for the higher
speed, slowing down causes increasing tail heaviness. This indicates
that pitch stability becomes divergent under normal flight conditions
which is not what I would expect from a standard category glider.

Bill D - former Lark owner.

Some of the gliders I fly will take a far greater weight of water in the
fin tank than even the heaviest dolly I have seen, getting airborne with
the tail dolly still attached is more embarassing than a danger.

Sorry to resurrect this thread, but the NTSB now has a preliminary
synopsis of this accident:

http://www.ntsb.gov/aviationquery/br...18X10736&key=1

One interesting aspect of the accident that I think is worthy of
discussion is this statement:

: As the tow plane and glider accelerated down the runway several
: witnesses noticed that the tail dolly remained attached to the
glider.
: The witnesses immediately advised the glider operations dispatcher,
: who in turn made the radio call “abort, abort, abort”.

Feel free to disagree, but I think that a better approach might have
been to tell the pilot exactly what is known:

"Uh, Lark One Two Three, be advised we have a report your tail dolly
is still on."

That gives the pilot the information they might not have, and leaves
the response to their initiative.

Please note that I am not criticizing. I wasn't there, and I don't
have all the facts. But I do think that this is something that is
worthy of discussion and reflection.

Also, I'm not saying that there isn't ever a situation where an abort
call is the thing to do. A good example of that would be the Clem
Bowman accident at Minden. In that case, the horizontal tailplane fell
off the aircraft right as the towplane was throttling up. In fact,
several people did make radio calls to that effect. Unfortunately, the
calls interfered with each other, and the result was an intelligible
squeal.

A tangential discussion is whether you should even make an advisory
call. I've talked to pilots who have said that they wouldn't even
advise someone that their gear was still retracted on final approach.
The thinking seems to be that the disruption caused by attending to
the gear late in the approach made things more dangerous than the gear-
up landing that would surely otherwise result. Personally, I think I
would generally choose to make that radio call, but would try to do it
in as neutral and informative fashion as possible.

Thanks, Bob K.

On 7/11/2012 2:58 PM, Bob Kuykendall wrote:
Sorry to resurrect this thread, but the NTSB now has a preliminary
synopsis of this accident:

http://www.ntsb.gov/aviationquery/br...18X10736&key=1

One interesting aspect of the accident that I think is worthy of
discussion is this statement:

: As the tow plane and glider accelerated down the runway several
: witnesses noticed that the tail dolly remained attached to the
glider.
: The witnesses immediately advised the glider operations dispatcher,
: who in turn made the radio call “abort, abort, abort”.

Feel free to disagree, but I think that a better approach might have
been to tell the pilot exactly what is known:

"Uh, Lark One Two Three, be advised we have a report your tail dolly
is still on."

That gives the pilot the information they might not have, and leaves
the response to their initiative.

Please note that I am not criticizing. I wasn't there, and I don't
have all the facts. But I do think that this is something that is
worthy of discussion and reflection.

I agree: a) it's worthy of discussion & reflection; b) providing "information"
as distinct from "pure commands" is almost surely "more likely useful" to a
pilot (assuming any message is heard/processed).

FWIW, I remember being distinctly surprised the first time I was in ground
vicinity to "an emergency situation" when someone grabbed a radio and (in a
high alarm tone of voice) radioed something or other about the situation. It
wasn't at all clear to me this was a good thing, for two obvious reasons: 1)
there was no imminent emergency/the glider was in controlled flight and
getting farther away from the ground every second; 2) the radio alarm - while
sensibly intentioned - was (to me) more alarming than the situation it was
intended to mitigate (& thus had potential to be a radio equivalent of Joe
Pilot misinterpreting a low-level rudder waggle from a tuggie). I no longer
even remember WHAT the situation was...but I DO remember my alarm at the
nature (not the intent) of the radio call. Happily, all ended well...

IMO/experience, there are few glider "emergencies" (whether launch or landing)
requiring "instant action" from Joe Pilot in order to avert disaster, and few
of those would likely even be visible to a casual ground observer. (The Clem
Bowman situation is the only one which comes immediately to mind, in fact.
What might be others?)


Also, I'm not saying that there isn't ever a situation where an abort
call is the thing to do. A good example of that would be the Clem
Bowman accident at Minden. In that case, the horizontal tailplane fell
off the aircraft right as the towplane was throttling up. In fact,
several people did make radio calls to that effect. Unfortunately, the
calls interfered with each other, and the result was an intelligible
squeal.

A tangential discussion is whether you should even make an advisory
call. I've talked to pilots who have said that they wouldn't even
advise someone that their gear was still retracted on final approach.
The thinking seems to be that the disruption caused by attending to
the gear late in the approach made things more dangerous than the gear-
up landing that would surely otherwise result. Personally, I think I
would generally choose to make that radio call, but would try to do it
in as neutral and informative fashion as possible.

Thanks, Bob K.


"Know one's audience," probably applies insofar as the desirability (or not)
of making an advisory call. That, and timing. I suspect few pilots would be
able to process and safely act upon an advisory call their gear is up if the
call arrives as the flare is entered, regardless of experience. (And yes, I
know it's been successfully done...) Personally, letting Joe PIC deal with the
consequences of an oversight is likely to be my choice, when I consider the
human reality of the time it takes for a ground observer (me!) to become aware
Joe PIC may be about to forget something desirable (e.g. extending the landing
gear), reaching a radio in a timely fashion, formulating a useful
message/delivering same, in sufficient time for Joe PIC to rectify the
situation safely. Each step requires time...

Bob - YMMV - W.

Advisory calls are useful in some circumstances - but I advise against a
gear up warning call once the pilot is established on final approach.

Having been the instructor in a situation where a student made a wheels
up approach - and someone overrode my decision - let me share.

We had a low time solo student working on accuracy. His task was to take
a winch launch, make a circuit and land within a set distance of a
reference point adjacent to the runway.

Traffic was a little heavy , and some genius wandered across the runway
as he was on final approach. Distraction happened. I was 50m from the
launch point abeam the reference point observing.

Some students preparing a twin noticed his wheel was up and asked if
they should call. I said no - at worst we were looking at a bit of grass
stain on the belly. They relayed to the launch point.

As he flared the launch marshal suddenly decided that the instructor
should be overruled because a club plane is about to make a wheels up
landing and this can't be right. He made an excited call to the pilot.
Pilot got a fright, left his left hand on the fully deployed airbrakes,
let go of the stick with his right hand to get the gear lever.

I guess I don't need to say the rest, but for information:
A guaranteed minor incident with the major damage being to an ego was
translated into substantial damage with risk of injury:

Big balloon - to about 2m height because the free stick was not trimmed.
Gear lever in the "Down" position but insecurely locked.
Left hand forgotten - so full brakes stay out on a G102.
Hand back on the stick to get the nose attitude right - unfortunately
the glider is no longer actually flying, it is describing a parabola due
to physics not aerodynamics.
First heavy impact on the nose knocked the gear lever off the lock.
Second impact on the wheel destroyed both parts of the cast gear
secondary motion unit.
Third impact and slide took the gear, and doors off and trailed bits
down the runway.

One lucky pilot, he only complained of a sore back. A little more energy
and he would be in a wheelchair.

A few lucky people, if he had put a wingtip in there were lots of people
within range of the missile.

So - from experience. Belly slide is a lot less dangerous. Even if is on
tar, and will result in one of those really expensive white stripes.

If you can make the call early, when the pilot has lots of time, maybe.
If the pilot is competent and you are confident he is attentive, not
dehydrated or distracted, maybe.

The point is - that the fact of the wheel being up, indicates that the
pilot is having difficulty with processing / workload / sequencing. Why
add to the load? Especially when it can go so spectacularly wrong.

Personally, the embarrassment is preferable to the risks.

squeal.

A tangential discussion is whether you should even make an advisory
call. I've talked to pilots who have said that they wouldn't even
advise someone that their gear was still retracted on final approach.
The thinking seems to be that the disruption caused by attending to
the gear late in the approach made things more dangerous than the gear-
up landing that would surely otherwise result. Personally, I think I
would generally choose to make that radio call, but would try to do it
in as neutral and informative fashion as possible.

Thanks, Bob K.


--
Bruce Greeff
T59D #1771

Le mercredi 11 juillet 2012 22:58:22 UTC+2, Bob Kuykendall a écrit*:
......
: As the tow plane and glider accelerated down the runway several
: witnesses noticed that the tail dolly remained attached to the
glider.
: The witnesses immediately advised the glider operations dispatcher,
: who in turn made the radio call “abort, abort, abort”.
.....
Feel free to disagree, but I think that a better approach might have
been to tell the pilot exactly what is known:
Thanks, Bob K.

We had a similar tail dolly incident some years ago at my club: take-off with the (modified, heavy) tail dolly on a Twin Astir. It turned into an accident when an instructor on the ground noticed this during take-off and radioed to abort. Unfortunately, the pilot did release when already flying and almost at the end of the runway. The sailplane went straight into the opposite bank of the large ditch surrounding the airfield. Result: one pilot seriously wounded, one passenger lightly wounded, the Twin total loss.

Some years before - we had no radio then -, I did fly that sailplane myself with the same tail dolly on (shame on me!), and I never noticed anything out of the ordinary. So I agree: by all means inform the pilot about what is happening, but wait until he has enough altitude to fly the airplane and check the controllability first. A few meters above the ground, you have no options left...

On Jul 12, 9:21*am, wrote:
Le mercredi 11 juillet 2012 22:58:22 UTC+2, Bob Kuykendall a écrit*:
.....

: As the tow plane and glider accelerated down the runway several
: witnesses noticed that the tail dolly remained attached to the
glider.
: The witnesses immediately advised the glider operations dispatcher,
: who in turn made the radio call “abort, abort, abort”.
.....
Feel free to disagree, but I think that a better approach might have
been to tell the pilot exactly what is known:
Thanks, Bob K.

We had a similar tail dolly incident some years ago at my club: take-off with the (modified, heavy) tail dolly on a Twin Astir. It turned into an accident when an instructor on the ground noticed this during take-off and radioed to abort. Unfortunately, the pilot did release when already flying and almost at the end of the runway. The sailplane went straight into the opposite bank of the large ditch surrounding the airfield. Result: one pilot seriously wounded, one passenger lightly wounded, the Twin total loss.

Some years before - we had no radio then -, I did fly that sailplane myself with the same tail dolly on (shame on me!), and I never noticed anything out of the ordinary. So I agree: by all means inform the pilot about what is happening, but wait until he has enough altitude to fly the airplane and check the controllability first. A few meters above the ground, you have no options left...

Agreed, a tail dolly doesn't require a panicky radio call.

A few years ago while working at a commercial glider operation, we got
a phone call from someone who had seen our Genesis II happily flying
with the tail dolly on it. The caller didn't want to make a radio
call himself and thoughtfully dropped the problem in our lap. Our
thought process from that point is possibly interesting.

The first thought was the glider is obviously controllable since it
has been in flight for 30 minutes or so with the pilot apparently
unaware of the dolly. We had been suggesting to the pilot he should
add weights to the rear post to move the CG aft for better handling
and climb anyway - the dolly had probably moved the CG just that
amount. We decided there was no urgency.

The second question is should we make the radio call. If we did, what
would we tell him? We discussed the landing and decided the correct
action would be to make a normal landing since the G2 is a nose wheel
glider and the dolly is very unlikely to touch the runway.

We decided the greatest risk was the dolly would fall off the glider
and land on someone. Since the dolly fit securely, we didn't think
this was much of a risk.

We put out word that no one should radio the pilot and just allow him
to make a normal landing. An uneventful landing happened after a
couple of hours. Now it was time to have a little fun at the pilots
expense.

I walked up to the glider with the pilot still in it and still unaware
of the dolly. "How was your flight", I asked. "Great", he said, "It
seemed to handle much better." "Well", I said, "we've been telling
you it would fly better if you moved the CG aft but we'd really prefer
you did it with the internal weights". He looked puzzled, then,
slowly, as he climbed out and saw the dolly, his expression changed to
astonishment and horror. He bought us dinner.

Originally Posted by BruceGreeff

Advisory calls are useful in some circumstances - but I advise against a
gear up warning call once the pilot is established on final approach.

Having been the instructor in a situation where a student made a wheels
up approach - and someone overrode my decision - let me share.

We had a low time solo student working on accuracy. His task was to take
a winch launch, make a circuit and land within a set distance of a
reference point adjacent to the runway.

Traffic was a little heavy , and some genius wandered across the runway
as he was on final approach. Distraction happened. I was 50m from the
launch point abeam the reference point observing.

Some students preparing a twin noticed his wheel was up and asked if
they should call. I said no - at worst we were looking at a bit of grass
stain on the belly. They relayed to the launch point.

As he flared the launch marshal suddenly decided that the instructor
should be overruled because a club plane is about to make a wheels up
landing and this can't be right. He made an excited call to the pilot.
Pilot got a fright, left his left hand on the fully deployed airbrakes,
let go of the stick with his right hand to get the gear lever.

I guess I don't need to say the rest, but for information:
A guaranteed minor incident with the major damage being to an ego was
translated into substantial damage with risk of injury:

Big balloon - to about 2m height because the free stick was not trimmed.
Gear lever in the "Down" position but insecurely locked.
Left hand forgotten - so full brakes stay out on a G102.
Hand back on the stick to get the nose attitude right - unfortunately
the glider is no longer actually flying, it is describing a parabola due
to physics not aerodynamics.
First heavy impact on the nose knocked the gear lever off the lock.
Second impact on the wheel destroyed both parts of the cast gear
secondary motion unit.
Third impact and slide took the gear, and doors off and trailed bits
down the runway.

One lucky pilot, he only complained of a sore back. A little more energy
and he would be in a wheelchair.

A few lucky people, if he had put a wingtip in there were lots of people
within range of the missile.

So - from experience. Belly slide is a lot less dangerous. Even if is on
tar, and will result in one of those really expensive white stripes.

If you can make the call early, when the pilot has lots of time, maybe.
If the pilot is competent and you are confident he is attentive, not
dehydrated or distracted, maybe.

The point is - that the fact of the wheel being up, indicates that the
pilot is having difficulty with processing / workload / sequencing. Why
add to the load? Especially when it can go so spectacularly wrong.

Personally, the embarrassment is preferable to the risks.

squeal.

A tangential discussion is whether you should even make an advisory
call. I've talked to pilots who have said that they wouldn't even
advise someone that their gear was still retracted on final approach.
The thinking seems to be that the disruption caused by attending to
the gear late in the approach made things more dangerous than the gear-
up landing that would surely otherwise result. Personally, I think I
would generally choose to make that radio call, but would try to do it
in as neutral and informative fashion as possible.

Thanks, Bob K.


--
Bruce Greeff
T59D #1771

While I agree with your sentiments and those above, after overflying the ODO at thirty feet I received a "glider on Final gear up" call. In my case, being a high hour AF guy, but low hour glider guy, I didn't panic. My aircraft is a Pilatus B4--I released the Airbrakes which collapse in at low to medium speeds (and I knew this), shoved the gear handle full forward and locked down (it's under the Airbrake lever), regrasped the Airbrakes and landed no incident with a nice touch down.

Now the Pilatus is nice in that I never had to take my right hand from the stick, and abrubt airbrake withdrawal adds a little nose up--so I basically leveled off slightly as I lowered the gear, lost about 2-3 knots, and when I puts the boards back out settled nicely back on approach.

I appreciated the save. imho, emergency type calls are good info--IF they are made in normal, non-sphincter tightening, standard comm voice--then they are either processed or ignored. I understand it's sometimes tough depending on the person, but it is the difference between good call and bad call.

Make the call the right way and pilots have a decision. Make it in a paniced, "OMG" type of call and most pilots will feel they have to act to avert disaster (andin a similarly panicked state) as opposed to make a decision.

Just my 2 Cents.

Squeaky

Important to remember who is PIC. I have seen several accident reports where a passenger or person on the ground reports "ABORT! ABORT!" or "RELEASE! RELEASE!". If the aircraft is in control, it is up to the PIC when to release, even in an "emergency"... and at 100ft is not the time to release, especially at my local airfield because you will end up in the trees. If there is truly a problem with the glider, and it does pitch up and stall, you do not want any surprises like this at 100ft! Might as well keep going since you are in control, hopefully to a safe bailout altitude and high enough to buy some time to figure out if the glider can fly or what you need to do to keep it flying. I know if some cool headed chap on the ground reported "Glider XXX your dolly is on, you may have some CG problems", I would definitely climb as high as possible before releasing.

Maybe instructors should suddenly yell RELEASE! RELEASE! at a safe tow altitude to get new pilots thinking about who is PIC?

Wind the clock.
Tom

On Sunday, July 15, 2012 11:58:15 PM UTC-4, tstock wrote:
Important to remember who is PIC. I have seen several accident reports where a passenger or person on the ground reports "ABORT! ABORT!" or "RELEASE! RELEASE!". If the aircraft is in control, it is up to the PIC when to release, even in an "emergency"... and at 100ft is not the time to release, especially at my local airfield because you will end up in the trees. If there is truly a problem with the glider, and it does pitch up and stall, you do not want any surprises like this at 100ft! Might as well keep going since you are in control, hopefully to a safe bailout altitude and high enough to buy some time to figure out if the glider can fly or what you need to do to keep it flying. I know if some cool headed chap on the ground reported "Glider XXX your dolly is on, you may have some CG problems", I would definitely climb as high as possible before releasing.

Maybe instructors should suddenly yell RELEASE! RELEASE! at a safe tow altitude to get new pilots thinking about who is PIC?

Wind the clock.
Tom

If I suspected CG problems I'd prefer to not release but go around and land with the towplane. No?