Buffalo Q400 crash

Just reading the WSJ reports on today's NTSB hearing concerning the
Q400 accident in Buffalo. I am not a pilot -- I know just enough about
flying to be dangerous. But I have a question for you folks who do
have real knowledge of aviation.

The transcript of the cockpit voice recorder says that once the
emergency began and they knew they were in serious trouble, the co-
pilot informed the pilot that she had "put the flaps up", 13 seconds
after the captain had lowered them to 15 degrees for landing. If stall
warnings and stick shakers/pushers are screaming at you that you are
in danger of stalling, isn't raising the flaps one of the worst things
you can do, since it *increases* your stall speed? In other words, if
you are already too slow with the flaps down, then you are *reallY*
too slow with them up. I would think they should have left the flaps
where they were, the nose where the stick pusher had it and just
poured on the power in the hope of gaining altitude before they hit
anything.

Am I right? Or, if not, please explain why.

Thanks --
/Don Allen

On May 12, 1:46*pm, Don wrote:
Just reading the WSJ reports on today's NTSB hearing concerning the
Q400 accident in Buffalo. I am not a pilot -- I know just enough about
flying to be dangerous. But I have a question for you folks who do
have real knowledge of aviation.

The transcript of the cockpit voice recorder says that once the
emergency began and they knew they were in serious trouble, the co-
pilot informed the pilot that she had "put the flaps up", 13 seconds
after the captain had lowered them to 15 degrees for landing. If stall
warnings and stick shakers/pushers are screaming at you that you are
in danger of stalling, isn't raising the flaps one of the worst things
you can do, since it *increases* your stall speed? In other words, if
you are already too slow with the flaps down, then you are *reallY*
too slow with them up. I would think they should have left the flaps
where they were, the nose where the stick pusher had it and just
poured on the power in the hope of gaining altitude before they hit
anything.

Am I right? Or, if not, please explain why.

Thanks --
/Don Allen

Don,

Standard practice is to wait until you have a positive rate of climb
before raising the flaps. Raising the flaps if the airplane was on
the verge of a stall would be a big mistake. Lowering the nose and
applying full power would be the best course of action, and once a
positive rate of climb could be achieved, then the flaps could be
raised.

wrote:

Standard practice is to wait until you have a positive rate of climb
before raising the flaps. Raising the flaps if the airplane was on
the verge of a stall would be a big mistake. Lowering the nose and
applying full power would be the best course of action, and once a
positive rate of climb could be achieved, then the flaps could be
raised.

There is some debate about that. For a wing stall, you are correct,
however, some have pointed out that the PIC's experience was recently on
Saabs, which can see tail stalls in icing conditions - the Q400 isn't
subject to tail stalls. A tail stall is most often first seen when the
flaps are extended, and the effect is for the nose to drop. The reaction
to a tail stall is to retract the flaps, and pull the nose up. Was that
what the captain was reacting to?

On May 12, 2:57*pm, James Robinson wrote:
wrote:

Standard practice is to wait until you have a positive rate of climb
before raising the flaps. *Raising the flaps if the airplane was on
the verge of a stall would be a big mistake. *Lowering the nose and
applying full power would be the best course of action, and once a
positive rate of climb could be achieved, then the flaps could be
raised.

There is some debate about that. *For a wing stall, you are correct,
however, some have pointed out that the PIC's experience was recently on
Saabs, which can see tail stalls in icing conditions - the Q400 isn't
subject to tail stalls. *A tail stall is most often first seen when the
flaps are extended, and the effect is for the nose to drop. *The reaction
to a tail stall is to retract the flaps, and pull the nose up. *Was that
what the captain was reacting to?

If that is the case, he had no business flying the Q400 because he
lacked sufficient training in type.

wrote:

James Robinson wrote:

*For a wing stall, you are correct, however, some have pointed out
that the PIC's experience was recently on Saabs, which can see tail
stalls in icing conditions - the Q400 isn't subject to tail stalls.
*A tail stall is most often first seen when the flaps are extended,
and the effect is for the nose to drop. *The reaction to a tail stall
is to retract the flaps, and pull the nose up. *Was that what the
captain was reacting to?

If that is the case, he had no business flying the Q400 because he
lacked sufficient training in type.

Listening to the NTSB hearings today, the Colgan chief pilots went to
great pains to say that they meet all FAA minimum training requirements.
They admitted that their training for the stick pusher was only in the
classroom prior to the accident, and that they never ran simulator
exercises to demonstrate how it worked. That seems like they missed the
mark with something that important. They changed their training after the
accident to include stick pusher simulations.

The Bombardier reps said that the aircraft isn't subject to tail stalls
in icing, but that it really isn't written anywhere in their flight
manuals. In fact, there was an error in one manual, where they recommend
training in tail stalls.

However, reading the cockpit transcripts suggests that the crew was less
than confident about flying in icing conditions. The first officer in
fact said that prior to her recent assignment to the northeast, all of
her flying had been out of Phoenix, and she had never flown when there
was ice buildup. She anticipated being upgraded to Saabs within six
months.

Overall, the crew was pretty lackadasical about procedures, and the first
officer seemed right out of her depth. Certainly not a seasoned
professional. The drop in airspeed was unnoticed, and the stall seemed to
catch them completely by surprise. One of the board asked each of the
Colgan check pilots to define "situational awareness", then made a speech
about how the crew was missing that important concept.

James Robinson wrote
The drop in airspeed was unnoticed, and the stall seemed
to catch them completely by surprise.

I wonder what the stall warning was doing all of this time?

Bob Moore

James Robinson wrote:
wrote:
Standard practice is to wait until you have a positive rate of climb
before raising the flaps. Raising the flaps if the airplane was on
the verge of a stall would be a big mistake. Lowering the nose and
applying full power would be the best course of action, and once a
positive rate of climb could be achieved, then the flaps could be
raised.

There is some debate about that. For a wing stall, you are correct,
however, some have pointed out that the PIC's experience was recently on
Saabs, which can see tail stalls in icing conditions - the Q400 isn't
subject to tail stalls. A tail stall is most often first seen when the
flaps are extended, and the effect is for the nose to drop. The reaction
to a tail stall is to retract the flaps, and pull the nose up. Was that
what the captain was reacting to?

Perhaps, but even that doesn't make sense either. The airplane stall
warning system/ stick shaker was activating. This would only indicate a
stall condition is imminent for the wing. The stall warning system does
not indicate anything about the tail, so the only corrective measure to
take for a stick shaker would be a conventional wing stall recovery,
such as full available power, prop forward, pitch down, don't bring up
the flaps until a positive rate of climb is achieved.

I'm not familiar with the specific stall recovery for that type, but you
get the idea. If the pilot pushed the stick over to recover from a
non-existent tail stall, that was a bad move. I haven't seen anything
to suggest that happened however.

Jessica wrote:

James Robinson wrote:

wrote:

Standard practice is to wait until you have a positive rate of climb
before raising the flaps. Raising the flaps if the airplane was on
the verge of a stall would be a big mistake. Lowering the nose and
applying full power would be the best course of action, and once a
positive rate of climb could be achieved, then the flaps could be
raised.

There is some debate about that. For a wing stall, you are correct,
however, some have pointed out that the PIC's experience was recently
on Saabs, which can see tail stalls in icing conditions - the Q400
isn't subject to tail stalls. A tail stall is most often first seen
when the flaps are extended, and the effect is for the nose to drop.
The reaction to a tail stall is to retract the flaps, and pull the
nose up. Was that what the captain was reacting to?

Perhaps, but even that doesn't make sense either. The airplane stall
warning system/ stick shaker was activating. This would only indicate
a stall condition is imminent for the wing. The stall warning system
does not indicate anything about the tail, so the only corrective
measure to take for a stick shaker would be a conventional wing stall
recovery, such as full available power, prop forward, pitch down,
don't bring up the flaps until a positive rate of climb is achieved.

The question is what to do when everything happens at the same time?
That is, after the flap setting is increased, the stick shaker stall
warning fires, and the nose pitches down. What would you do then? The
stick shaker is only an indication of an impending stall, and there are
probably a few MPH margin left, but the increased flap setting might have
started a tailplane stall, on aircraft that have that tendency.

Immediately retracting the flaps might be the best course, along with
either level flight with increased power or slightly pushing the nose
down to keep the speed up. Pulling on the control column likely wouldn't
be a good idea, unless the pitch down was extreme. I don't know.

I'm not familiar with the specific stall recovery for that type, but
you get the idea. If the pilot pushed the stick over to recover from
a non-existent tail stall, that was a bad move. I haven't seen
anything to suggest that happened however.

The FDR shows moderate backpressure (20 lb, 40 lbs total) momentarily
applied to the control columns on both sides in response to the stick
shaker. This causes the aircraft to pitch up. When the aircraft pitches
up, the pressure is relaxed, to be reapplied by the left side when the
stick pusher is fired as the speed drops and the wing stalls.

Clearly, pulling on the control columns was the wrong thing to do, so why
did they both do it? Pushing should have been the instinctive reaction
to the stick shaker. I'm trying to figure out what else might have been
in their minds to generate the opposite reaction.

On 16 May, 13:25, James Robinson wrote:
Jessica wrote:

James Robinson wrote:

wrote:

Standard practice is to wait until you have a positive rate of climb
before raising the flaps. *Raising the flaps if the airplane was on
the verge of a stall would be a big mistake. *Lowering the nose and
applying full power would be the best course of action, and once a
positive rate of climb could be achieved, then the flaps could be
raised.

There is some debate about that. *For a wing stall, you are correct,
however, some have pointed out that the PIC's experience was recently
on Saabs, which can see tail stalls in icing conditions - the Q400
isn't subject to tail stalls. *A tail stall is most often first seen
when the flaps are extended, and the effect is for the nose to drop.
The reaction to a tail stall is to retract the flaps, and pull the
nose up. *Was that what the captain was reacting to?

Perhaps, but even that doesn't make sense either. *The airplane stall
warning system/ stick shaker was activating. *This would only indicate
a stall condition is imminent for the wing. *The stall warning system
does not indicate anything about the tail, so the only corrective
measure to take for a stick shaker would be a conventional wing stall
recovery, such as full available power, prop forward, pitch down,
don't bring up the flaps until a positive rate of climb is achieved.

The question is what to do when everything happens at the same time? *
That is, after the flap setting is increased, the stick shaker stall
warning fires, and the nose pitches down. What would you do then? *The
stick shaker is only an indication of an impending stall, and there are
probably a few MPH margin left, but the increased flap setting might have
started a tailplane stall, on aircraft that have that tendency.

Immediately retracting the flaps might be the best course, along with
either level flight with increased power or slightly pushing the nose
down to keep the speed up. Pulling on the control column likely wouldn't
be a good idea, unless the pitch down was extreme. I don't know.

I'm not familiar with the specific stall recovery for that type, but
you get the idea. *If the pilot pushed the stick over to recover from
a non-existent tail stall, that was a bad move. *I haven't seen
anything to suggest that happened however.

The FDR shows moderate backpressure (20 lb, 40 lbs total) momentarily
applied to the control columns on both sides in response to the stick
shaker.

If memory serves me correctly, from my reading of NTSB material
the two control column force
transducers are *not* representative of the forces on the
two pilots' control columns.

There are two force sensors but I interpreted the explanation
to mean that it cannot be determined how much force each pilot
was applying.

http://www.ntsb.gov/Dockets/Aviation...027/417236.pdf
3.5.4. Control Column Forces
"With the system operating normally (for example,
disconnect not pulled), there is no way to determine
if pilot, copilot or both are flying."

There is more in the original doc. Quite complex and hard to
follow.

On Sat, 16 May 2009 12:25:49 +0000 (UTC), James Robinson wrote:

Clearly, pulling on the control columns was the wrong thing to do, so why
did they both do it? Pushing should have been the instinctive reaction
to the stick shaker. I'm trying to figure out what else might have been
in their minds to generate the opposite reaction.

Sex?
--
Bear Bottoms
Private Attorney General