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Andy[_1_]
February 19th 09, 03:44 PM
The following references are provided, without my comment, for those
interested in the subject of stall recognition and recovery.


http://online.wsj.com/article/SB123492905826906821.html?mod=djemalertNEWS

reports on the referenced fatal accident:

http://www.ntsb.gov/ntsb/GenPDF.asp?id=DCA05MA003&rpt=fa

http://www.ntsb.gov/Publictn/2007/AAR0701.pdf


Andy

Ramy
February 19th 09, 08:02 PM
On Feb 19, 7:44*am, Andy > wrote:
> The following references are provided, without my comment, for those
> interested in the subject of stall recognition and recovery.
>
> http://online.wsj.com/article/SB123492905826906821.html?mod=djemalert....
>
> reports on the referenced fatal accident:
>
> http://www.ntsb.gov/ntsb/GenPDF.asp?id=DCA05MA003&rpt=fa
>
> http://www.ntsb.gov/Publictn/2007/AAR0701.pdf
>
> Andy

I simply don't buy it. How any pilot with even basic experience, not
to mention thousands of hours, will react to a stall warning by
pulling on the stick/yoke?? and "pitched up to a 31-degree angle" ??
It's not like they were so close to the ground that they had to pullup
to clear it. As usual, the NTSB rather put the blame on the pilots...

Ramy

Mike the Strike
February 19th 09, 08:19 PM
Linking the present accident to the earlier CRJ one doesn't look very
reasonable. The CRJ accident was clearly the result of stupidity on
behalf of the two pilots - flying close to the operating envelope of
the aircraft, failing to deal with an impending stall and then failing
to follow engine-start procedures.

It's certainly possible that the latest accident resulted from control
instability due to ice buildup - large uncommanded control movements
are well known.

I don't see the connection between them.

Mike

Nyal Williams[_2_]
February 19th 09, 08:30 PM
I, for one, hope that all accidents are pilot error; we must be able to
depend on our equipment all the time. Otherwise, there is no hope.

At 20:02 19 February 2009, Ramy wrote:
>On Feb 19, 7:44=A0am, Andy wrote:
>> The following references are provided, without my comment, for those
>> interested in the subject of stall recognition and recovery.
>>
>>
>http://online.wsj.com/article/SB123492905826906821.html?mod=3Ddjemalert..=
>..
>>
>> reports on the referenced fatal accident:
>>
>> http://www.ntsb.gov/ntsb/GenPDF.asp?id=3DDCA05MA003&rpt=3Dfa
>>
>> http://www.ntsb.gov/Publictn/2007/AAR0701.pdf
>>
>> Andy
>
>I simply don't buy it. How any pilot with even basic experience, not
>to mention thousands of hours, will react to a stall warning by
>pulling on the stick/yoke?? and "pitched up to a 31-degree angle" ??
>It's not like they were so close to the ground that they had to pullup
>to clear it. As usual, the NTSB rather put the blame on the pilots...
>
>Ramy
>

Ramy
February 19th 09, 09:46 PM
I wish so too, but the reality is different. The last 2 commercial
aviation accidents proves it - birds and ice (probably). Luckily in
the first case there was a big river to land in.
The only thing we can really depend on is statistics...

Ramy

On Feb 19, 12:30*pm, Nyal Williams > wrote:
> I, for one, hope that all accidents are pilot error; we must be able to
> depend on our equipment all the time. *Otherwise, there is no hope.
>
> At 20:02 19 February 2009, Ramy wrote:
>
>
>
> >On Feb 19, 7:44=A0am, Andy *wrote:
> >> The following references are provided, without my comment, for those
> >> interested in the subject of stall recognition and recovery.
>
> >http://online.wsj.com/article/SB123492905826906821.html?mod=3Ddjemale....
> >..
>
> >> reports on the referenced fatal accident:
>
> >>http://www.ntsb.gov/ntsb/GenPDF.asp?id=3DDCA05MA003&rpt=3Dfa
>
> >>http://www.ntsb.gov/Publictn/2007/AAR0701.pdf
>
> >> Andy
>
> >I simply don't buy it. How any pilot with even basic experience, not
> >to mention thousands of hours, will react to a stall warning by
> >pulling on the stick/yoke?? and "pitched up to a 31-degree angle" ??
> >It's not like they were so close to the ground that they had to pullup
> >to clear it. As usual, the NTSB rather put the blame on the pilots...
>
> >Ramy- Hide quoted text -
>
> - Show quoted text -

Darryl Ramm
February 20th 09, 12:43 AM
On Feb 19, 12:02*pm, Ramy > wrote:
> On Feb 19, 7:44*am, Andy > wrote:
>
> > The following references are provided, without my comment, for those
> > interested in the subject of stall recognition and recovery.
>
> >http://online.wsj.com/article/SB123492905826906821.html?mod=djemalert....
>
> > reports on the referenced fatal accident:
>
> >http://www.ntsb.gov/ntsb/GenPDF.asp?id=DCA05MA003&rpt=fa
>
> >http://www.ntsb.gov/Publictn/2007/AAR0701.pdf
>
> > Andy
>
> I simply don't buy it. How any pilot with even basic experience, not
> to mention thousands of hours, will react to a stall warning by
> pulling on the stick/yoke?? and "pitched up to a 31-degree angle" ??
> It's not like they were so close to the ground that they had to pullup
> to clear it. As usual, the NTSB rather put the blame on the pilots...
>
> Ramy

What you think the pilots should not be blamed becasue they could not
possibly be so incompetent to conduct the amazing list of bad
decisions and errors that made? That's an interesting defense.

Well if that accident chain does not deserve to be blamed on the
pilots I don't know what does. Lets see, lets climb the sucker to
FL410, with the AP in rate mode so is really slow when we get there,
lets not monitor airspeed during this (even though we know are pushing
the envelope). Lets not follow engine failure checklists properly,
lets not pitch over and correctly do a windmills start, etc. (I can't
recall if it as established how much they knew about core lock if at
all, but they failed to execute basic restart procedure). Lets not
declare our emergency and try to cover up for a while hoping we can
get ourselves out of this hole. Lets not fly the sucker when all else
goes wrong and maintain glide to any of several airports etc. etc.
etc. This flight crew deserved evey bit of cricism they got. Some
aspects of training programs and the core lock on the GE engines etc.
need to be addressed but are very distant factors in my opinion.

And dude if that does ### convince you these folks were an accident
waiting to happen read ### cockpit transcript. Dude.

Most commentators came down hard on the pilots as well, including
several magazine articles.

There are multiple fatal accidents where things as "simple" as
misunderstanding stick shaker/pusher vs. Mach buffeting, obstructed
pitot/static systems (and fighting the stick pusher thinking it was
Mach induced, etc. etc.). However none of those are even close to the
chain of events this flight crew managed to accomplish.

Darryl

Ramy
February 20th 09, 02:20 AM
On Feb 19, 4:43*pm, Darryl Ramm > wrote:
> On Feb 19, 12:02*pm, Ramy > wrote:
>
>
>
>
>
> > On Feb 19, 7:44*am, Andy > wrote:
>
> > > The following references are provided, without my comment, for those
> > > interested in the subject of stall recognition and recovery.
>
> > >http://online.wsj.com/article/SB123492905826906821.html?mod=djemalert...
>
> > > reports on the referenced fatal accident:
>
> > >http://www.ntsb.gov/ntsb/GenPDF.asp?id=DCA05MA003&rpt=fa
>
> > >http://www.ntsb.gov/Publictn/2007/AAR0701.pdf
>
> > > Andy
>
> > I simply don't buy it. How any pilot with even basic experience, not
> > to mention thousands of hours, will react to a stall warning by
> > pulling on the stick/yoke?? and "pitched up to a 31-degree angle" ??
> > It's not like they were so close to the ground that they had to pullup
> > to clear it. As usual, the NTSB rather put the blame on the pilots...
>
> > Ramy
>
> What you think the pilots should not be blamed becasue they could not
> possibly be so incompetent to conduct the amazing list of bad
> decisions and errors that made? That's an interesting defense.
>
> Well if that accident chain does not deserve to be blamed on the
> pilots I don't know what does. Lets see, lets climb the sucker to
> FL410, with the AP in rate mode so is really slow when we get there,
> lets not monitor airspeed during this (even though we know are pushing
> the envelope). Lets not follow engine failure checklists properly,
> lets not pitch over and correctly do a windmills start, etc. (I can't
> recall if it as established how much they knew about core lock if at
> all, but they failed to execute basic restart procedure). Lets not
> declare our emergency and try to cover up for a while hoping we can
> get ourselves out of this hole. Lets not fly the sucker when all else
> goes wrong and maintain glide to any of several airports etc. etc.
> etc. This flight crew deserved evey bit of cricism they got. Some
> aspects of training programs and the core lock on the GE engines etc.
> need to be addressed but are very distant factors in my opinion.
>
> And dude if that does ### convince you these folks were an accident
> waiting to happen read ### cockpit transcript. Dude.
>
> Most commentators came down hard on the pilots as well, including
> several magazine articles.
>
> There are multiple fatal accidents where things as "simple" as
> misunderstanding stick shaker/pusher vs. Mach buffeting, obstructed
> pitot/static systems (and fighting the stick pusher thinking it was
> Mach induced, etc. etc.). However none of those are even close to *the
> chain of events this flight crew managed to accomplish.
>
> Darryl- Hide quoted text -
>
> - Show quoted text -

I don't think we are talking about the same accidents Darryl. I was
referring to the recent one in the article. And I don't say pilots
should not be blamed for many possible mistakes they do. All I say is
that I don't buy the claim that experience pilot purposely pulled the
yoke and piched up to 31 degree angle without recognizing he is
stalling the aircraft. Unless I missread the article this is a
complete BS.

Ramy

Eric Greenwell
February 20th 09, 03:17 AM
Nyal Williams wrote:
> I, for one, hope that all accidents are pilot error; we must be able to
> depend on our equipment all the time. Otherwise, there is no hope.

If you mean pilot error instead of equipment failure, I agree; if you
mean, pilots manipulating the equipment improperly, I probably don't
agree. My belief is it's easier to change the equipment than the pilot.
Examples: automatic control connections, docile stall behavior, spoiler
that don't open spontaneously if unlocked, ditto for canopies.

--
Eric Greenwell - Washington State, USA
* Change "netto" to "net" to email me directly

* Updated! "Transponders in Sailplanes" http://tinyurl.com/y739x4
* New Jan '08 - sections on Mode S, TPAS, ADS-B, Flarm, more

* "A Guide to Self-launching Sailplane Operation" at www.motorglider.org

February 20th 09, 03:24 AM
On Feb 19, 9:17*pm, Eric Greenwell > wrote:
> Nyal Williams wrote:
> > I, for one, hope that all accidents are pilot error; we must be able to
> > depend on our equipment all the time. *Otherwise, there is no hope.
>
> If you mean pilot error instead of equipment failure, I agree; if you
> mean, pilots manipulating the equipment improperly, I probably don't
> agree. My belief is it's easier to change the equipment than the pilot.
> Examples: automatic control connections, docile stall behavior, spoiler
> that don't open spontaneously if unlocked, ditto for canopies.
>
> --
> Eric Greenwell - Washington State, USA
> * Change "netto" to "net" to email me directly
>
> * Updated! "Transponders in Sailplanes"http://tinyurl.com/y739x4
> * * * New Jan '08 - sections on Mode S, TPAS, ADS-B, Flarm, more
>
> * "A Guide to Self-launching Sailplane Operation" atwww.motorglider.org

Very interesting information here: http://www.cnn.com/2009/US/02/19/buffalo.crash.ils/index.html

Nyal Williams[_2_]
February 20th 09, 04:30 AM
Of course I meant the former. I can't even get to the second idea from my
statement; that's pilot causing equipment failure and therefore pilot
error. Pulling off the wings by exceeding Vne is pilot error. We agree.

At 03:17 20 February 2009, Eric Greenwell wrote:
>Nyal Williams wrote:
>> I, for one, hope that all accidents are pilot error; we must be able
to
>> depend on our equipment all the time. Otherwise, there is no hope.
>
>If you mean pilot error instead of equipment failure, I agree; if you
>mean, pilots manipulating the equipment improperly, I probably don't
>agree. My belief is it's easier to change the equipment than the pilot.

>Examples: automatic control connections, docile stall behavior, spoiler
>that don't open spontaneously if unlocked, ditto for canopies.
>
>--
>Eric Greenwell - Washington State, USA
>* Change "netto" to "net" to email me directly
>
>* Updated! "Transponders in Sailplanes" http://tinyurl.com/y739x4
> * New Jan '08 - sections on Mode S, TPAS, ADS-B, Flarm, more
>
>* "A Guide to Self-launching Sailplane Operation" at
www.motorglider.org
>

Tuno
February 20th 09, 05:22 AM
Andy, thanks for posting these.

I read the NTSB report and was bewildered ... how could such otherwise
competent pilots perform so recklessly?

Mostly I want to know if there's something I can glean from it for my
own flying. There was probably a two-person instance of crowd behavior
at play (comment, BB?), but the way I talk to myself in the cockpit, I
don't feel immune.

2NO

Darryl Ramm
February 20th 09, 05:46 AM
On Feb 19, 6:20*pm, Ramy > wrote:
> On Feb 19, 4:43*pm, Darryl Ramm > wrote:
>
>
>
> > On Feb 19, 12:02*pm, Ramy > wrote:
>
> > > On Feb 19, 7:44*am, Andy > wrote:
>
> > > > The following references are provided, without my comment, for those
> > > > interested in the subject of stall recognition and recovery.
>
> > > >http://online.wsj.com/article/SB123492905826906821.html?mod=djemalert...
>
> > > > reports on the referenced fatal accident:
>
> > > >http://www.ntsb.gov/ntsb/GenPDF.asp?id=DCA05MA003&rpt=fa
>
> > > >http://www.ntsb.gov/Publictn/2007/AAR0701.pdf
>
> > > > Andy
>
> > > I simply don't buy it. How any pilot with even basic experience, not
> > > to mention thousands of hours, will react to a stall warning by
> > > pulling on the stick/yoke?? and "pitched up to a 31-degree angle" ??
> > > It's not like they were so close to the ground that they had to pullup
> > > to clear it. As usual, the NTSB rather put the blame on the pilots...
>
> > > Ramy
>
> > What you think the pilots should not be blamed becasue they could not
> > possibly be so incompetent to conduct the amazing list of bad
> > decisions and errors that made? That's an interesting defense.
>
> > Well if that accident chain does not deserve to be blamed on the
> > pilots I don't know what does. Lets see, lets climb the sucker to
> > FL410, with the AP in rate mode so is really slow when we get there,
> > lets not monitor airspeed during this (even though we know are pushing
> > the envelope). Lets not follow engine failure checklists properly,
> > lets not pitch over and correctly do a windmills start, etc. (I can't
> > recall if it as established how much they knew about core lock if at
> > all, but they failed to execute basic restart procedure). Lets not
> > declare our emergency and try to cover up for a while hoping we can
> > get ourselves out of this hole. Lets not fly the sucker when all else
> > goes wrong and maintain glide to any of several airports etc. etc.
> > etc. This flight crew deserved evey bit of cricism they got. Some
> > aspects of training programs and the core lock on the GE engines etc.
> > need to be addressed but are very distant factors in my opinion.
>
> > And dude if that does ### convince you these folks were an accident
> > waiting to happen read ### cockpit transcript. Dude.
>
> > Most commentators came down hard on the pilots as well, including
> > several magazine articles.
>
> > There are multiple fatal accidents where things as "simple" as
> > misunderstanding stick shaker/pusher vs. Mach buffeting, obstructed
> > pitot/static systems (and fighting the stick pusher thinking it was
> > Mach induced, etc. etc.). However none of those are even close to *the
> > chain of events this flight crew managed to accomplish.
>
> > Darryl- Hide quoted text -
>
> > - Show quoted text -
>
> I don't think we are talking about the same accidents Darryl. I was
> referring to the recent one in the article. And I don't say pilots
> should not be blamed for many possible mistakes they do. All I say is
> that I don't buy the claim that experience pilot purposely pulled the
> yoke and piched up to 31 degree angle without recognizing he is
> stalling the aircraft. Unless I missread the article this is a
> complete BS.
>
> Ramy

I am sure we can all think of cases where we read "pilot error" and
know that it is wrong finger pointing. However your reverse argument
that people should not blame pilots because they could not pull back/
pitch up an aircraft into a deep stall or fail to recover from a stall
is fanciful. And I'm not judging anything to do with the current
accident, just saying there is no way to say pilots would not do
something just because you think an experienced pilot would not do it.

While I misunderstood what accident you were referring to there are
enough concerning things circulating already about the recent accident
- enough to guarantee I'll read the report carefully. But I would not
rush to jump to conclusions either way.

In the following accidents forget the flight crew's involvement in
arriving at the point bad things happen, but their efforts to do just
what you say an experienced crew would not do is what I'm pointing
out...

1974 B727 fatal crash, crew screwed up checklists and left pitot anti-
ice off and then mistook what was happening as they climbed with a
blocked pitot, even though they noted things looked strange and fought
the stick pusher all the way into a deep stall. Oh they had the nose
up 25 degrees higher than it should be...

http://flyingsc.com/learn/res/impossible_climb.html


1972 BEA Trident Heathrow. The crew deactivated the stick pusher after
first incorrectly retracting the wing LE droop, and stalled. Lots of
possible contributing factors but it is hard to argue this was not
pilot error in how they handled the stall (may have been complicated
by the possible medical condition of the pilot).

http://en.wikipedia.org/wiki/British_European_Airways_Flight_548
and
http://www.super70s.com/super70s/Tech/Aviation/Disasters/72-06-18(Trident).asp

There are others out there, including likely cases of mishandling of
stall or mach tuck when autopilots either automatically or manually
disconnect and pilots are suddenly faced with unexpected control
forces. Is that mach tuck or stick push? Is that mach buffer or stall
buffet/stick shaker? Do I push or pull?

You should also appreciate how detatched from the reality of what was
happening to their aircraft that the two pilots who screwed up at FL
410 were. They stalled. What made it so amazing was all the other
stuff they did wrong. However even with obvious blame on the crew I
thought the NTSB did a good job highlighting training deficiencies -
especially issue with doing simulator stall training only at
relatively low altitude and not letting them go though to full stick
pusher stage - which may confuse a crew if the stick pusher does
activate. (which kind of mirrors my concern about the need for full on
spin training in GA aircraft and gliders. I think it is unforgivable
to just teach recovery from an the very earliest incipient stall and
pilots should be exposed to deep stalls and spins and their recovery
(and yes I know the irony is some people will die in spin training)).



Darryl

February 20th 09, 07:58 AM
On Feb 19, 9:46*pm, Darryl Ramm > wrote:
> On Feb 19, 6:20*pm, Ramy > wrote:
>
>
>
>
>
> > On Feb 19, 4:43*pm, Darryl Ramm > wrote:
>
> > > On Feb 19, 12:02*pm, Ramy > wrote:
>
> > > > On Feb 19, 7:44*am, Andy > wrote:
>
> > > > > The following references are provided, without my comment, for those
> > > > > interested in the subject of stall recognition and recovery.
>
> > > > >http://online.wsj.com/article/SB123492905826906821.html?mod=djemalert...
>
> > > > > reports on the referenced fatal accident:
>
> > > > >http://www.ntsb.gov/ntsb/GenPDF.asp?id=DCA05MA003&rpt=fa
>
> > > > >http://www.ntsb.gov/Publictn/2007/AAR0701.pdf
>
> > > > > Andy
>
> > > > I simply don't buy it. How any pilot with even basic experience, not
> > > > to mention thousands of hours, will react to a stall warning by
> > > > pulling on the stick/yoke?? and "pitched up to a 31-degree angle" ??
> > > > It's not like they were so close to the ground that they had to pullup
> > > > to clear it. As usual, the NTSB rather put the blame on the pilots....
>
> > > > Ramy
>
> > > What you think the pilots should not be blamed becasue they could not
> > > possibly be so incompetent to conduct the amazing list of bad
> > > decisions and errors that made? That's an interesting defense.
>
> > > Well if that accident chain does not deserve to be blamed on the
> > > pilots I don't know what does. Lets see, lets climb the sucker to
> > > FL410, with the AP in rate mode so is really slow when we get there,
> > > lets not monitor airspeed during this (even though we know are pushing
> > > the envelope). Lets not follow engine failure checklists properly,
> > > lets not pitch over and correctly do a windmills start, etc. (I can't
> > > recall if it as established how much they knew about core lock if at
> > > all, but they failed to execute basic restart procedure). Lets not
> > > declare our emergency and try to cover up for a while hoping we can
> > > get ourselves out of this hole. Lets not fly the sucker when all else
> > > goes wrong and maintain glide to any of several airports etc. etc.
> > > etc. This flight crew deserved evey bit of cricism they got. Some
> > > aspects of training programs and the core lock on the GE engines etc.
> > > need to be addressed but are very distant factors in my opinion.
>
> > > And dude if that does ### convince you these folks were an accident
> > > waiting to happen read ### cockpit transcript. Dude.
>
> > > Most commentators came down hard on the pilots as well, including
> > > several magazine articles.
>
> > > There are multiple fatal accidents where things as "simple" as
> > > misunderstanding stick shaker/pusher vs. Mach buffeting, obstructed
> > > pitot/static systems (and fighting the stick pusher thinking it was
> > > Mach induced, etc. etc.). However none of those are even close to *the
> > > chain of events this flight crew managed to accomplish.
>
> > > Darryl- Hide quoted text -
>
> > > - Show quoted text -
>
> > I don't think we are talking about the same accidents Darryl. I was
> > referring to the recent one in the article. And I don't say pilots
> > should not be blamed for many possible mistakes they do. All I say is
> > that I don't buy the claim that experience pilot purposely pulled the
> > yoke and piched up to 31 degree angle without recognizing he is
> > stalling the aircraft. Unless I missread the article this is a
> > complete BS.
>
> > Ramy
>
> I am sure we can all think of cases where we read "pilot error" and
> know that it is wrong finger pointing. However your reverse argument
> that people should not blame pilots because they could not pull back/
> pitch up an aircraft into a deep stall or fail to recover from a stall
> is fanciful. And I'm not judging anything to do with the current
> accident, just saying there is no way to say pilots would not do
> something just because you think an experienced pilot would not do it.
>
> While I misunderstood what accident you were referring to there are
> enough concerning things circulating already about the recent accident
> - enough to guarantee I'll read the report carefully. But I would not
> rush to jump to conclusions either way.
>
> In the following accidents forget the flight crew's involvement in
> arriving at the point bad things happen, but their efforts to do just
> what you say an experienced crew would not do is what I'm pointing
> out...
>
> 1974 B727 fatal crash, crew screwed up checklists and left pitot anti-
> ice off and then mistook what was happening as they climbed with a
> blocked pitot, even though they noted things looked strange and fought
> the stick pusher all the way into a deep stall. Oh they had the nose
> up 25 degrees higher than it should be...
>
> http://flyingsc.com/learn/res/impossible_climb.html
>
> 1972 BEA Trident Heathrow. The crew deactivated the stick pusher after
> first incorrectly retracting the wing LE droop, and stalled. Lots of
> possible contributing factors but it is hard to argue this was not
> pilot error in how they handled the stall (may have been complicated
> by the possible medical condition of the pilot).
>
> http://en.wikipedia.org/wiki/British_European_Airways_Flight_548
> andhttp://www.super70s.com/super70s/Tech/Aviation/Disasters/72-06-18(Tri....
>
> There are others out there, including likely cases of mishandling of
> stall or mach tuck when autopilots either automatically or manually
> disconnect and pilots are suddenly faced with unexpected control
> forces. Is that mach tuck or stick push? Is that mach buffer or stall
> buffet/stick shaker? Do I push or pull?
>
> You should also appreciate how detatched from the reality of what was
> happening to their aircraft that the two pilots who screwed up at FL
> 410 were. They stalled. What made it so amazing was all the other
> stuff they did wrong. However even with obvious blame on the crew I
> thought the NTSB did a good job highlighting training deficiencies -
> especially issue with doing simulator stall training only at
> relatively low altitude and not letting them go though to full stick
> pusher stage - which may confuse a crew if the stick pusher does
> activate. (which kind of mirrors my concern about the need for full on
> spin training in GA aircraft and gliders. I think it is unforgivable
> to just teach recovery from an the very earliest incipient stall and
> pilots should be exposed to deep stalls and spins and their recovery
> (and yes I know the irony is some people will die in spin training)).
>
> Darryl- Hide quoted text -
>
> - Show quoted text -

Thanks for the eye openning links. Makes me wanting to replace my
airline tickets with a cruise...
Interesting to learn that blocked pitot may cause higher reading. I
always expected it to show lower reading. I am wondering if this is
true for gliders ASI as well.

Ramy

vontresc
February 20th 09, 02:15 PM
On Feb 20, 1:58*am, wrote:
> On Feb 19, 9:46*pm, Darryl Ramm > wrote:
>
>
>
>
>
> > On Feb 19, 6:20*pm, Ramy > wrote:
>
> > > On Feb 19, 4:43*pm, Darryl Ramm > wrote:
>
> > > > On Feb 19, 12:02*pm, Ramy > wrote:
>
> > > > > On Feb 19, 7:44*am, Andy > wrote:
>
> > > > > > The following references are provided, without my comment, for those
> > > > > > interested in the subject of stall recognition and recovery.
>
> > > > > >http://online.wsj.com/article/SB123492905826906821.html?mod=djemalert...
>
> > > > > > reports on the referenced fatal accident:
>
> > > > > >http://www.ntsb.gov/ntsb/GenPDF.asp?id=DCA05MA003&rpt=fa
>
> > > > > >http://www.ntsb.gov/Publictn/2007/AAR0701.pdf
>
> > > > > > Andy
>
> > > > > I simply don't buy it. How any pilot with even basic experience, not
> > > > > to mention thousands of hours, will react to a stall warning by
> > > > > pulling on the stick/yoke?? and "pitched up to a 31-degree angle" ??
> > > > > It's not like they were so close to the ground that they had to pullup
> > > > > to clear it. As usual, the NTSB rather put the blame on the pilots...
>
> > > > > Ramy
>
> > > > What you think the pilots should not be blamed becasue they could not
> > > > possibly be so incompetent to conduct the amazing list of bad
> > > > decisions and errors that made? That's an interesting defense.
>
> > > > Well if that accident chain does not deserve to be blamed on the
> > > > pilots I don't know what does. Lets see, lets climb the sucker to
> > > > FL410, with the AP in rate mode so is really slow when we get there,
> > > > lets not monitor airspeed during this (even though we know are pushing
> > > > the envelope). Lets not follow engine failure checklists properly,
> > > > lets not pitch over and correctly do a windmills start, etc. (I can't
> > > > recall if it as established how much they knew about core lock if at
> > > > all, but they failed to execute basic restart procedure). Lets not
> > > > declare our emergency and try to cover up for a while hoping we can
> > > > get ourselves out of this hole. Lets not fly the sucker when all else
> > > > goes wrong and maintain glide to any of several airports etc. etc.
> > > > etc. This flight crew deserved evey bit of cricism they got. Some
> > > > aspects of training programs and the core lock on the GE engines etc.
> > > > need to be addressed but are very distant factors in my opinion.
>
> > > > And dude if that does ### convince you these folks were an accident
> > > > waiting to happen read ### cockpit transcript. Dude.
>
> > > > Most commentators came down hard on the pilots as well, including
> > > > several magazine articles.
>
> > > > There are multiple fatal accidents where things as "simple" as
> > > > misunderstanding stick shaker/pusher vs. Mach buffeting, obstructed
> > > > pitot/static systems (and fighting the stick pusher thinking it was
> > > > Mach induced, etc. etc.). However none of those are even close to *the
> > > > chain of events this flight crew managed to accomplish.
>
> > > > Darryl- Hide quoted text -
>
> > > > - Show quoted text -
>
> > > I don't think we are talking about the same accidents Darryl. I was
> > > referring to the recent one in the article. And I don't say pilots
> > > should not be blamed for many possible mistakes they do. All I say is
> > > that I don't buy the claim that experience pilot purposely pulled the
> > > yoke and piched up to 31 degree angle without recognizing he is
> > > stalling the aircraft. Unless I missread the article this is a
> > > complete BS.
>
> > > Ramy
>
> > I am sure we can all think of cases where we read "pilot error" and
> > know that it is wrong finger pointing. However your reverse argument
> > that people should not blame pilots because they could not pull back/
> > pitch up an aircraft into a deep stall or fail to recover from a stall
> > is fanciful. And I'm not judging anything to do with the current
> > accident, just saying there is no way to say pilots would not do
> > something just because you think an experienced pilot would not do it.
>
> > While I misunderstood what accident you were referring to there are
> > enough concerning things circulating already about the recent accident
> > - enough to guarantee I'll read the report carefully. But I would not
> > rush to jump to conclusions either way.
>
> > In the following accidents forget the flight crew's involvement in
> > arriving at the point bad things happen, but their efforts to do just
> > what you say an experienced crew would not do is what I'm pointing
> > out...
>
> > 1974 B727 fatal crash, crew screwed up checklists and left pitot anti-
> > ice off and then mistook what was happening as they climbed with a
> > blocked pitot, even though they noted things looked strange and fought
> > the stick pusher all the way into a deep stall. Oh they had the nose
> > up 25 degrees higher than it should be...
>
> >http://flyingsc.com/learn/res/impossible_climb.html
>
> > 1972 BEA Trident Heathrow. The crew deactivated the stick pusher after
> > first incorrectly retracting the wing LE droop, and stalled. Lots of
> > possible contributing factors but it is hard to argue this was not
> > pilot error in how they handled the stall (may have been complicated
> > by the possible medical condition of the pilot).
>
> >http://en.wikipedia.org/wiki/British_European_Airways_Flight_548
> > andhttp://www.super70s.com/super70s/Tech/Aviation/Disasters/72-06-18(Tri...
>
> > There are others out there, including likely cases of mishandling of
> > stall or mach tuck when autopilots either automatically or manually
> > disconnect and pilots are suddenly faced with unexpected control
> > forces. Is that mach tuck or stick push? Is that mach buffer or stall
> > buffet/stick shaker? Do I push or pull?
>
> > You should also appreciate how detatched from the reality of what was
> > happening to their aircraft that the two pilots who screwed up at FL
> > 410 were. They stalled. What made it so amazing was all the other
> > stuff they did wrong. However even with obvious blame on the crew I
> > thought the NTSB did a good job highlighting training deficiencies -
> > especially issue with doing simulator stall training only at
> > relatively low altitude and not letting them go though to full stick
> > pusher stage - which may confuse a crew if the stick pusher does
> > activate. (which kind of mirrors my concern about the need for full on
> > spin training in GA aircraft and gliders. I think it is unforgivable
> > to just teach recovery from an the very earliest incipient stall and
> > pilots should be exposed to deep stalls and spins and their recovery
> > (and yes I know the irony is some people will die in spin training)).
>
> > Darryl- Hide quoted text -
>
> > - Show quoted text -
>
> Thanks for the eye openning links. Makes me wanting to replace my
> airline tickets with a cruise...
> Interesting to learn that blocked pitot may cause higher reading. I
> always expected it to show lower reading. I am wondering if this is
> true for gliders ASI as well.
>
> Ramy- Hide quoted text -
>
> - Show quoted text -

Any ASI will behave that way. If the pitot becomes blocked the ASI
turns into an Altimeter. The pressure in the pitot side of the ASI
remains constant, and the static pressure decreases as you climb. Net
result is that the ASI will show increasing airspeed as you climb, and
decreasing airspeed as you descend. This of course assumes that the
static isn't plugged up as well.

Pete

February 20th 09, 02:21 PM
I'm not saying these guys didn't screw up, but lets give them a break.
They're descending at night, in the soup and icing up. What's going
through their heads? Is the de-icing system working right? Are we
experiencing more icing than this system can handle? If the stab ices
up it may result in a steep nose down situation. If the pitot ices up,
we may get a false stall warning???? About then the damned "stick-
pusher" shoves the nose way down. Stick-shaker OK, stick-pusher BAD
idea.
JJ

Andy[_1_]
February 20th 09, 03:23 PM
On Feb 20, 7:21*am, wrote:
>. Stick-shaker OK, stick-pusher BAD idea.
> JJ

The stick pusher will only activate if other stall warning, or low
speed protection, systems have failed to prevent the aircraft becoming
critically close to stall speed (strictly stall alpha). Why do you
think that entering a stall, which for some aircraft may be
unrecoverable, is better than having a stick pusher prevent the stall?

Andy

Eric Greenwell
February 21st 09, 02:41 AM
Nyal Williams wrote:
> Of course I meant the former. I can't even get to the second idea from my
> statement;

I pulled the trigger too quickly on that one - sorry! I should have
looked at things more carefully.

--
Eric Greenwell - Washington State, USA
* Change "netto" to "net" to email me directly

* Updated! "Transponders in Sailplanes" http://tinyurl.com/y739x4
* New Jan '08 - sections on Mode S, TPAS, ADS-B, Flarm, more

* "A Guide to Self-launching Sailplane Operation" at www.motorglider.org

Nyal Williams[_2_]
February 21st 09, 04:15 AM
Not a problem; this has been an interesting thread; time for it to die.


At 02:41 21 February 2009, Eric Greenwell wrote:
>Nyal Williams wrote:
>> Of course I meant the former. I can't even get to the second idea
from
>my
>> statement;
>
>I pulled the trigger too quickly on that one - sorry! I should have
>looked at things more carefully.
>
>--
>Eric Greenwell - Washington State, USA
>* Change "netto" to "net" to email me directly
>
>* Updated! "Transponders in Sailplanes" http://tinyurl.com/y739x4
> * New Jan '08 - sections on Mode S, TPAS, ADS-B, Flarm, more
>
>* "A Guide to Self-launching Sailplane Operation" at
www.motorglider.org
>

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