AF447 wreckage found
Join Date: Feb 2010
Location: Hotel
Posts: 102
Likes: 0
Received 0 Likes
on
0 Posts
Quote from Air France:
"The crew, made up of three skilled pilots, demonstrated a totally professional attitude and were committed to carrying out their task to the very end and Air France wishes to pay tribute to them."
I'm not ready to put all the blame on the pilots. However, a statement like this at this time makes me think they have hired "Bagdad Bob" as their press officer. Is this just French arrogance or do they know something we don't?
"The crew, made up of three skilled pilots, demonstrated a totally professional attitude and were committed to carrying out their task to the very end and Air France wishes to pay tribute to them."
I'm not ready to put all the blame on the pilots. However, a statement like this at this time makes me think they have hired "Bagdad Bob" as their press officer. Is this just French arrogance or do they know something we don't?
Join Date: May 2011
Location: Germany
Age: 40
Posts: 13
Likes: 0
Received 0 Likes
on
0 Posts
On a Dutch news site here ( Inmiddels 77 lichamen uit ) the following claim is made (translated into English):
Reading this kind of surprised me, as I didn't have the impression that they wanted to fly over the storm, but it would explain why they suddenly went into this steep climb.
The pilots wanted, thus becomes clear from the 'current conclusions' from the investigation into the two black boxes of the plane, to fly over a lightning storm, but were prevented from this because it wasn't possible due to the temperature to fly to that height.
Join Date: May 2011
Location: London
Posts: 5
Likes: 0
Received 0 Likes
on
0 Posts
Apologies: I posted essentially the same message as this a bit later (below) - not having noticed that there would be a delay pending moderation.
Last edited by 000tfm000; 31st May 2011 at 13:10. Reason: Message mainly duplicated by later post
Join Date: May 2011
Location: here
Posts: 131
Likes: 0
Received 0 Likes
on
0 Posts
"The crew, made up of three skilled pilots, demonstrated a totally professional attitude and were committed to carrying out their task to the very end and Air France wishes to pay tribute to them."
I'm not ready to put all the blame on the pilots. However, a statement like this at this time makes me think they have hired "Bagdad Bob" as their press officer. Is this just French arrogance or do they know something we don't?
I'm not ready to put all the blame on the pilots. However, a statement like this at this time makes me think they have hired "Bagdad Bob" as their press officer. Is this just French arrogance or do they know something we don't?
Join Date: Aug 2009
Location: Germany
Age: 67
Posts: 1,777
Likes: 0
Received 0 Likes
on
0 Posts
Hi,
When I read the Air France statement .. I ask myself (already posted)
Why Air France will make such statement ? .. as maybe the final report will go in a contrary way .....
Maybe they know more on the CVR-FDR that what we know ?
I'm not ready to put all the blame on the pilots. However, a statement like this at this time makes me think they have hired "Bagdad Bob" as their press officer. Is this just French arrogance or do they know something we don't?
Why Air France will make such statement ? .. as maybe the final report will go in a contrary way .....
Maybe they know more on the CVR-FDR that what we know ?
Join Date: Oct 2004
Location: Out of the pollution.
Posts: 673
Likes: 0
Received 0 Likes
on
0 Posts
had they done NOTHING or atleast followed the Unreliable Airspeed Abnormal Checklist and turn to the GPS page for speed and Alt..
No they weren't hero's. If (and I say) the BEA report is correct they were idiots.
Like the A340 crew in YYZ
No they weren't hero's. If (and I say) the BEA report is correct they were idiots.
Like the A340 crew in YYZ
Join Date: Feb 2010
Location: Hotel
Posts: 102
Likes: 0
Received 0 Likes
on
0 Posts
"there can't be any doubt whatsoever that these men did everything they could to save the plane."
So you mean sitting with the stick pulled fully back for 3,5 minutes while you are descending with 10000 fpm demonstrates a "totally professional attitude"?
What I'm saying is, if AF know more than we do, they might have a point. But, from what we know so far... absolutely not.
Just as I won't put all the blame on the pilots before I have the final report you should be careful to completely clear them of responsibility. Can we agree on that?
So you mean sitting with the stick pulled fully back for 3,5 minutes while you are descending with 10000 fpm demonstrates a "totally professional attitude"?
What I'm saying is, if AF know more than we do, they might have a point. But, from what we know so far... absolutely not.
Just as I won't put all the blame on the pilots before I have the final report you should be careful to completely clear them of responsibility. Can we agree on that?
Join Date: May 2011
Location: London
Posts: 5
Likes: 0
Received 0 Likes
on
0 Posts
Stall warning system a contributory factor?
To me as a lawyer with an interest in aviation safety, the preliminary report implies that the design of the stall warning system may have been a major contributory factor in this accident.
The PF was confronted with conflicting signals as well as degraded instruments. Nevertheless, at quite an early stage, his inputs commanded nose-down pitch. He appears successfully to have initiated a recovery. What he needed to do, was to develop this response further.
However, the stall warning system did not recognise this. It did not encourage the PF to develop his solution further. On the contrary, it sounded a stall warning. This is essentially because it could not reward the improving trend which the PF had initiated: it could only recognise the threshold above which the stall warning should be available (<60knots = stall warning unavailable; >60knots = stall warning available).
A correct interpretation of the stall warning would possibly have been difficult in any situation. Particularly in the difficult conditions which must have prevailed at the time, the PF may well have inferred that there was a causal connection between the stall warning and his most recent command: ie, nose-down. Naturally, he would have wished to reverse the cause. So he would command nose-up instead.
What is worse, the PF would now have learned by experience that commanding nose-down pitch would "cause" a stall warning. He would have been reluctant to try it again.
Therefore, my tentative view is that the stall warning at this stage in the attempted recovery gave precisely the wrong message to the PF. It may well have been an important step in the "critical path" of the accident.
I think we should not rush to blame the pilots: the term "pilot error" sometimes disguises the degree to which "human error" has been induced by automatic systems.
The PF was confronted with conflicting signals as well as degraded instruments. Nevertheless, at quite an early stage, his inputs commanded nose-down pitch. He appears successfully to have initiated a recovery. What he needed to do, was to develop this response further.
However, the stall warning system did not recognise this. It did not encourage the PF to develop his solution further. On the contrary, it sounded a stall warning. This is essentially because it could not reward the improving trend which the PF had initiated: it could only recognise the threshold above which the stall warning should be available (<60knots = stall warning unavailable; >60knots = stall warning available).
A correct interpretation of the stall warning would possibly have been difficult in any situation. Particularly in the difficult conditions which must have prevailed at the time, the PF may well have inferred that there was a causal connection between the stall warning and his most recent command: ie, nose-down. Naturally, he would have wished to reverse the cause. So he would command nose-up instead.
What is worse, the PF would now have learned by experience that commanding nose-down pitch would "cause" a stall warning. He would have been reluctant to try it again.
Therefore, my tentative view is that the stall warning at this stage in the attempted recovery gave precisely the wrong message to the PF. It may well have been an important step in the "critical path" of the accident.
I think we should not rush to blame the pilots: the term "pilot error" sometimes disguises the degree to which "human error" has been induced by automatic systems.
Join Date: Aug 2003
Location: Scotland
Posts: 240
Likes: 0
Received 0 Likes
on
0 Posts
Late but hopefully useful
This thread is galloping forwards so fast that I'm replying to something three pages ago, but it was only a few hours ago, and it needs answered because it is another daft blind alley.
Someone said:
I think you will find that is completely normal, and even a microsecond of thought will tell you why. Think "parked on the taxiway". There's a strong chance the wing is fully stalled, but we'll supress the stall warning until we've got some speed up, thank-you.
Someone said:
I can't believe anybody would certify an airliner that is stalled but the stall warning mutes because the pitot static system senses less than 60 knots. That is nuts.
Join Date: May 2011
Location: here
Posts: 131
Likes: 0
Received 0 Likes
on
0 Posts
So you mean sitting with the stick pulled fully back for 3,5 minutes while you are descending with 10000 fpm demonstrates a "totally professional attitude"?
No, what I'm saying is at that point, to them pulling on that stick appeared to be the best way to save the plane.
Considering what we know now (which is, as has been said numerous times, still very little), that was likely not the case and probably the final report will prove us, sitting in our comfy chairs, right and those men who died that night wrong.
But what then? It's so easy to shrug it off, label them as idiots and go back to business, while learning from their mistakes will be work and will cost money. But I think we owe it to them.
Join Date: Jun 2010
Location: Stairways to heaven
Posts: 346
Likes: 0
Received 0 Likes
on
0 Posts
Patty: agree totally.
as another earlier post pointed out. At 350, flight controls neutral and correct trust setting should get you out at lower alt with faulty IAS. not rated on 330 but sure as hell works for most other tubes with wings that I flown in the past.
as another earlier post pointed out. At 350, flight controls neutral and correct trust setting should get you out at lower alt with faulty IAS. not rated on 330 but sure as hell works for most other tubes with wings that I flown in the past.
Originally Posted by CJ Driver
Someone said:
Quote:
I think you will find that is completely normal, and even a microsecond of thought will tell you why. Think "parked on the taxiway". There's a strong chance the wing is fully stalled, but we'll supress the stall warning until we've got some speed up, thank-you.
Quote:
I can't believe anybody would certify an airliner that is stalled but the stall warning mutes because the pitot static system senses less than 60 knots. That is nuts.
Join Date: May 2011
Location: here
Posts: 131
Likes: 0
Received 0 Likes
on
0 Posts
the preliminary report implies that the design of the stall warning system may have been a major contributory factor in this accident.
The PF was confronted with conflicting signals as well as degraded instruments. Nevertheless, at quite an early stage, his inputs commanded nose-down pitch. He appears successfully to have initiated a recovery. What he needed to do, was to develop this response further.
However, the stall warning system did not recognise this. It did not encourage the PF to develop his solution further. On the contrary, it sounded a stall warning.
The PF was confronted with conflicting signals as well as degraded instruments. Nevertheless, at quite an early stage, his inputs commanded nose-down pitch. He appears successfully to have initiated a recovery. What he needed to do, was to develop this response further.
However, the stall warning system did not recognise this. It did not encourage the PF to develop his solution further. On the contrary, it sounded a stall warning.
2 h 10 min 16:
(...)The airplane’s pitch attitude increased progressively beyond 10 degrees and the plane started
to climb. The PF made nose-down control inputs and alternately left and right roll inputs. The
vertical speed, which had reached 7,000 ft/min, dropped to 700 ft/min and the roll varied
between 12 degrees right and 10 degrees left. The speed displayed on the left side increased
sharply to 215 kt (Mach 0.68) (...)
At 2 h 10 min 51, the stall warning was triggered again. The thrust levers were positioned
in the TO/GA detent and the PF maintained nose-up inputs.(...)
Around fifteen seconds later, the speed displayed on the ISIS increased sharply towards 185 kt;it was then consistent with the other recorded speed.
So IAS was well above 60 kt at this point. The stall warning simply meant they were going into a stall.
The only time a reappearing stall warning due to nose down / increasing IAS is mentioned is much later:
At 2 h 12 min 02, (...) Around fifteen seconds later, the PF made pitch-down inputs. In
the following moments, the angle of attack decreased, the speeds became valid again and the
stall warning sounded again.
But the report doesn't say anything at all about the PF's reaction to that warning.
Join Date: Jun 2009
Location: Belgium
Age: 43
Posts: 77
Likes: 0
Received 0 Likes
on
0 Posts
What is worse, the PF would now have learned by experience that commanding nose-down pitch would "cause" a stall warning. He would have been reluctant to try it again.
Join Date: Dec 2001
Location: England
Posts: 1,389
Likes: 0
Received 0 Likes
on
0 Posts
@ costamaia
@CWatters
Quote:
Why wasn't full power applied?
Wasn't it?
From the BEA 27 May report (http://www.bea.aero/fr/enquetes/vol....i2011.en.pdf):
"At 2 h 10 min 51, the stall warning was triggered again. The thrust levers were positioned in the TO/GA detent and the PF maintained nose-up inputs."
"The altitude was then about 35,000 ft, the angle of attack exceeded 40 degrees and the vertical speed was about -10,000 ft/min. The airplane’s pitch attitude did not exceed 15 degrees and the engines’ N1’s were close to 100%."
I meant later when they still had a high rate of descent..
...although I admit it doesn't mention what they did with the throttles after that.
@CWatters
Quote:
Why wasn't full power applied?
Wasn't it?
From the BEA 27 May report (http://www.bea.aero/fr/enquetes/vol....i2011.en.pdf):
"At 2 h 10 min 51, the stall warning was triggered again. The thrust levers were positioned in the TO/GA detent and the PF maintained nose-up inputs."
"The altitude was then about 35,000 ft, the angle of attack exceeded 40 degrees and the vertical speed was about -10,000 ft/min. The airplane’s pitch attitude did not exceed 15 degrees and the engines’ N1’s were close to 100%."
At 2 h 12 min 02, the PF said "I don’t have any more indications", and the PNF said "we have no valid indications". At that moment, the thrust levers were in the IDLE detent and the engines’ N1’s were at 55%. Around fifteen seconds later, the PF made pitch-down inputs. In the following moments, the angle of attack decreased, the speeds became valid again and the stall warning sounded again.
Join Date: May 2011
Location: Paris
Posts: 2
Likes: 0
Received 0 Likes
on
0 Posts
BEA report unclear
I am French, so I have the happiness to read the BEA report in the text.
It is very confused and incomplete. Don't trust it too much and don't exhaust yourself trying to make a coherent theory from it.
For example, there is not enough informations to understand why the A330 climbed and stalled at 38 000 ft :
> the pilot gives «ordres à cabrer» (pitch-up orders)
> then the PF gives «ordres à piquer» (pitch-down orders)
and then «le PF mantient ses ordres à cabrer» (the PF keeps giving pitch-up ordres)
Obviously, there is something missing here : when did the PF resume his pitch-up orders after having tried the pitch-down orders ? And why ?
The whole report is like this : ill-phrased, hardly understandable and lacunar.
Be careful when you use this report : I thing some very important informations are missing (or withheld ?).
It is very confused and incomplete. Don't trust it too much and don't exhaust yourself trying to make a coherent theory from it.
For example, there is not enough informations to understand why the A330 climbed and stalled at 38 000 ft :
> the pilot gives «ordres à cabrer» (pitch-up orders)
> then the PF gives «ordres à piquer» (pitch-down orders)
and then «le PF mantient ses ordres à cabrer» (the PF keeps giving pitch-up ordres)
Obviously, there is something missing here : when did the PF resume his pitch-up orders after having tried the pitch-down orders ? And why ?
The whole report is like this : ill-phrased, hardly understandable and lacunar.
Be careful when you use this report : I thing some very important informations are missing (or withheld ?).
Join Date: Dec 2001
Location: England
Posts: 1,389
Likes: 0
Received 0 Likes
on
0 Posts
Its probably been said before in the last 55 pages but,
If you lose sensible airspeed and altimeter indications, disregard all and fly attitude and zero bank angle for normal cruise flight with relevant manual throttle setting. Been there, done that.
Try it in the sim.
If you lose sensible airspeed and altimeter indications, disregard all and fly attitude and zero bank angle for normal cruise flight with relevant manual throttle setting. Been there, done that.
Try it in the sim.
Join Date: Nov 2006
Location: SoCalif
Posts: 896
Likes: 0
Received 0 Likes
on
0 Posts
Optional, or Mandatory
Shogan1977, from Der Spiegel:
Money is in play here, I'm sure. Typically, if the component maker or airframe builder make a Service Bulletin mandatory, they pay for it. If the SB is optional, the airline pays. I've known airlines who refuse to pay for SB that are to correct defects, regardless.
Quote:
The manufacturer Thales was well aware of the catastrophic consequences of a failure of the speed sensors as early as 2005. At the time, the French company concluded that such a failure could "cause plane crashes."
A total of 32 cases are known in which A330 crews got into difficulties because the speed sensors failed. In all the cases, the planes had pitot sensors from Thales, which were significantly more prone to failure than a rival model from an American manufacturer.
But none of the responsible parties intervened. In 2007, Airbus merely "recommended" that the sensors be replaced. Air France took that as a reason not to carry out the costly work -- and it even got official blessing for doing so. The European Aviation Safety Agency wrote that it currently saw "no unsafe condition that warrants a mandatory modification of the Thales pitot tubes."
The manufacturer Thales was well aware of the catastrophic consequences of a failure of the speed sensors as early as 2005. At the time, the French company concluded that such a failure could "cause plane crashes."
A total of 32 cases are known in which A330 crews got into difficulties because the speed sensors failed. In all the cases, the planes had pitot sensors from Thales, which were significantly more prone to failure than a rival model from an American manufacturer.
But none of the responsible parties intervened. In 2007, Airbus merely "recommended" that the sensors be replaced. Air France took that as a reason not to carry out the costly work -- and it even got official blessing for doing so. The European Aviation Safety Agency wrote that it currently saw "no unsafe condition that warrants a mandatory modification of the Thales pitot tubes."
Join Date: Jun 2009
Location: USA
Posts: 64
Likes: 0
Received 0 Likes
on
0 Posts
Quote...
The passengers, who had just a short time before been pressed into the backs of their seats, were now being held into their seats only by their seatbelts. "At this moment, I would have feared for my life even if I was sitting in the passenger cabin," said one A330 pilot after reading the BEA report. That the plane was in freefall would have been clear to all on board. The nose of the plane pointed skyward at an angle of 16 degrees. "That's more than immediately following takeoff," the pilot said.
Unquote.
Having flown many times and thinking about my built-in senses of horizontal and gravitational, I tend to agree.
The passengers, who had just a short time before been pressed into the backs of their seats, were now being held into their seats only by their seatbelts. "At this moment, I would have feared for my life even if I was sitting in the passenger cabin," said one A330 pilot after reading the BEA report. That the plane was in freefall would have been clear to all on board. The nose of the plane pointed skyward at an angle of 16 degrees. "That's more than immediately following takeoff," the pilot said.
Unquote.
Having flown many times and thinking about my built-in senses of horizontal and gravitational, I tend to agree.
The passengers were never pressed into the backs of their seats, since the aircraft was losing speed. They were never held only by their seatbelts, since that would require negative G's, which they never would have seen as a result of the maneuvers described in the BEA "note".
The initial pitch up would not have been much different than experienced when rotating for taking off. The ride over the top would have certainly been noticed, when they went from a high rate of climb to high rate of descent, but passenger's behinds would have always been solidly in their seats, not dangling from their seatbelts, as suggested in the article.
Once descending, the rate of descent didn't change, so passengers would have only sensed that the nose was pointed up, somewhat like an initial climbout on takeoff on say a DC-10 or 757. There also would have been heavy buffeting. Given that they were flying at night in a storm, the passengers would have had no outside references to know what was happening, and would not have known they were falling. A clue would have been the change in cabin pressure, but how many passengers would connect that with rapid descent?
To me the unanswered question is then - why didn't the pilots realise they were pointed up towards the sky and they were falling like a leaf?
They could see the altitude bleading away extremely rapidly. Could they not read the attitude also? At least they knew they were pulling up!
It seems ridiculous in hindsight that pulling up over that length of time and not reducing the descent MUST only mean you are not diving, you are stalled. Easy to say now, but those guys are supposed to be professionals, yes?