AF 447 report out
Pedro:
The following response to you is based on a briefing a few years old. What you describe looks to already be in place. There may be small changes to this that I am unaware of. (I don't fly the A330, but the system design for this feature looks pretty straightforward to me).
The handgrip includes two switches :
- A/P disconnect/sidestick priority push-button (On top of sidestick).
- Push-to-talk button (Trigger, on front of sidestick).
Captain and First Officer priority lights, located in the glareshield, provide indication if either has taken the priority for his sidestick orders.
A sidestick priority lights are next to each pilkot's EFIS CTL display.
a. The Captain's side stick priority light comes on green-"Captain" if he pushes his priority button and the other pilot has the stick deflected.
The F/O sees a red arrow pointing at the Captain.
b. The FO's side stick priority light comes on green-"F/O" if he pushes his priority button and the other pilot has the stick deflected.
The Captain sees a red arrow pointing at the F/O.
c. If either has set the stick to neutral, then the other pilot pushing the button yields no other light, but does show a red arrow pointing at the other pilot.
The process is "c" is how I presume most changes in "I have control" "you have control" take place. Stable platform, no deflection at time of control change. Standard CRM techniques would apply.
However, there is this to consider ...
Priority logic
• Normal operation : Captain and First Officer inputs are algebrically summed.
• Autopilot disconnect pushbutton is used at take-over button.
• Last pilot who depressed and holds take-over button has priority ; other pilot’s inputs ignored.
• Priority annunciation : (three things happen)
- in front of each pilot on glareshield
- ECAM message
- audio warning.
• Normal control restored when both buttons are released.
It would seem that sufficient thought went into this design that typically rated transport pilots would have no trouble in establishing who has the controls, and gives warning when there is a control change.
The following response to you is based on a briefing a few years old. What you describe looks to already be in place. There may be small changes to this that I am unaware of. (I don't fly the A330, but the system design for this feature looks pretty straightforward to me).
The handgrip includes two switches :
- A/P disconnect/sidestick priority push-button (On top of sidestick).
- Push-to-talk button (Trigger, on front of sidestick).
Captain and First Officer priority lights, located in the glareshield, provide indication if either has taken the priority for his sidestick orders.
A sidestick priority lights are next to each pilkot's EFIS CTL display.
a. The Captain's side stick priority light comes on green-"Captain" if he pushes his priority button and the other pilot has the stick deflected.
The F/O sees a red arrow pointing at the Captain.
b. The FO's side stick priority light comes on green-"F/O" if he pushes his priority button and the other pilot has the stick deflected.
The Captain sees a red arrow pointing at the F/O.
c. If either has set the stick to neutral, then the other pilot pushing the button yields no other light, but does show a red arrow pointing at the other pilot.
The process is "c" is how I presume most changes in "I have control" "you have control" take place. Stable platform, no deflection at time of control change. Standard CRM techniques would apply.
However, there is this to consider ...
Priority logic
• Normal operation : Captain and First Officer inputs are algebrically summed.
• Autopilot disconnect pushbutton is used at take-over button.
• Last pilot who depressed and holds take-over button has priority ; other pilot’s inputs ignored.
• Priority annunciation : (three things happen)
- in front of each pilot on glareshield
- ECAM message
- audio warning.
• Normal control restored when both buttons are released.
It would seem that sufficient thought went into this design that typically rated transport pilots would have no trouble in establishing who has the controls, and gives warning when there is a control change.
Last edited by Lonewolf_50; 17th Sep 2012 at 17:35.
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Voice from the past.
Seventy years ago they sat me in a Stearman. It had an altimeter, needle&ball and rev counter (might have had a panel compass, can't remember). "Fly", they said. So I did (by attitude), for my first sixty hours.
Often wondered why the US Army Air Corps played that trick on me. Now I know.
Often wondered why the US Army Air Corps played that trick on me. Now I know.
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Foxmoth, where do you find 3 seconds before pulling back?
My recollection of the “stirring mayonnaise” graphic that it was about 7 or 8 seconds before a consistent pull back. Before that, the predominant movements were in roll, the pitch-up/pitch down inputs were alternating, and some here speculated that they were partly if not wholly inadvertent – the results of a right hand movement being to tend to pull back with full left aileron and forward with full right. [see:
http://www.pprune.org/tech-log/46839...ml#post6819601 ]
I thought it was only after the significant left/right movements ceased – thought by some to indicate that the roll had been brought under control – that Bonin did his sustained pull-up.
My recollection of the “stirring mayonnaise” graphic that it was about 7 or 8 seconds before a consistent pull back. Before that, the predominant movements were in roll, the pitch-up/pitch down inputs were alternating, and some here speculated that they were partly if not wholly inadvertent – the results of a right hand movement being to tend to pull back with full left aileron and forward with full right. [see:
http://www.pprune.org/tech-log/46839...ml#post6819601 ]
I thought it was only after the significant left/right movements ceased – thought by some to indicate that the roll had been brought under control – that Bonin did his sustained pull-up.
Last edited by chrisN; 17th Sep 2012 at 17:53.
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I got this directly from the report http://www.bea.aero/docspa/2009/f-cp...p090601.en.pdf
Page 62 shows FO pitch command, at 2 seconds after A/P drop out he starts a substantial aft input - if you look it gets to about half deflection before easing off, so not just a slight back pull! It does not in my view, tie in with the roll inputs at all if you examine the traces. He does not give a forward input until about 11 second in, but by this time the nose is way up, and he does not get the pitch below about 10 degrees, interestingly it is only when the captain walks in(at about 1:30 in) that he actually puts in and holds full up (well after the aircraft had stalled at About 1:10 in). Pages 62-64 show all these inputs.
Page 62 shows FO pitch command, at 2 seconds after A/P drop out he starts a substantial aft input - if you look it gets to about half deflection before easing off, so not just a slight back pull! It does not in my view, tie in with the roll inputs at all if you examine the traces. He does not give a forward input until about 11 second in, but by this time the nose is way up, and he does not get the pitch below about 10 degrees, interestingly it is only when the captain walks in(at about 1:30 in) that he actually puts in and holds full up (well after the aircraft had stalled at About 1:10 in). Pages 62-64 show all these inputs.
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As with his Sim experience with approach to Stall, when he hears the STALLWARN, he inputs Aft Stick when the "instructor" expects it....Unfortunately for them all, the Stall Warn quits when the IAS drops below 60knots, so it affirms his action, though it is quite lethal. " 'There Captain', no Stall.."
But at this point, as has been presented ad nauseum on the other threads, it is far too late to recover the flight path, it would require inputs unheard of in all their experience combined.
But at this point, as has been presented ad nauseum on the other threads, it is far too late to recover the flight path, it would require inputs unheard of in all their experience combined.
For the whole ten days I lived in blissful delusion I have finally managed to kill this 
thread.
Please, please, please:
Go read the report.
If you don't understand what is written, come back and ask.
If your intention is not to provide some low quality entertainment through airing spectacularly flawed theories, don't theorize until you are sure you understand the facts.
thread.Please, please, please:
Go read the report.
If you don't understand what is written, come back and ask.
If your intention is not to provide some low quality entertainment through airing spectacularly flawed theories, don't theorize until you are sure you understand the facts.
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If your intention is not to provide some low quality entertainment through airing spectacularly flawed theories, don't theorize until you are sure you understand the facts.
I guess it also applies to those who have not flown the different FBW and still they belittle statements of those who have .....
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Pitot tubes Icing,in this day and age it should be unheard of!
This was the start of the problem,how did Airbus get away with fitting inferior pitot tubes with inferior heating elements?
This was the start of the problem,how did Airbus get away with fitting inferior pitot tubes with inferior heating elements?
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Not an A330 pilot
Just watched the Channel 4 documentary.
Well I am not an A330 pilot, but then the three on this flight did not seem to be A330 pilots either. Systems operators perhaps, who did not know how the system worked.
HOW can anyone be so stupid as to hold an aircraft in the stall for 38,000 feet !!!
Air Chance should have a close look at their pilot training and actually insist they fly the aircraft from time to time and not just for the first and last two minutes of each flight.
I would rather be a passenger on a fully automated aircraft rather than an Air Chance flight with a crew like that.
Air France = Air Chance.
(From what I know about the A330, which is "squiddly dit", if the pilots had set 85% power and 5°deg pitch up then they could have just flown on at a safe speed. Think I'll avoid flying with Air Chance.)
Well I am not an A330 pilot, but then the three on this flight did not seem to be A330 pilots either. Systems operators perhaps, who did not know how the system worked.
HOW can anyone be so stupid as to hold an aircraft in the stall for 38,000 feet !!!
Air Chance should have a close look at their pilot training and actually insist they fly the aircraft from time to time and not just for the first and last two minutes of each flight.
I would rather be a passenger on a fully automated aircraft rather than an Air Chance flight with a crew like that.
Air France = Air Chance.
(From what I know about the A330, which is "squiddly dit", if the pilots had set 85% power and 5°deg pitch up then they could have just flown on at a safe speed. Think I'll avoid flying with Air Chance.)
Last edited by iamhere; 21st Sep 2012 at 11:20.
iamhere:
Based on the BEA report and the information released from the DFDR and CVR, the crew never grasped that they had stalled the aircraft. That would seem to be why they never put in stall recovery control inputs to unstall the aircraft. My estimation of that glaring error is that when they recognized that the airspeeds had gone awry, they made the assumption that stall warnings that they were receiving were spurious.
Can't prove it, however, so I am left guessing.
A more cogent question might be "why did they fly it into the stall?" I am not convinced that a 5 degree nose up pitch held ad infinitum would do other than slowly fly them into a stall, or slowly fly them to their service ceiling. (Or, that setting might have worked out just fine until the airspeed indicators became reliable again. Guessing, yet again. )
You will note from the BEA reports that the crew had already voiced their concern that temperatures at altitude did not suit their original plan to climb to FL 380 -- conditions had not progressed quite as forecast and they were concerned with that effect on aircraft performance.
A few threads ago, Clandestino, PJ2, and a few others went back and forth about the difference between pitch and power settings based on getting the charts and checklists out, and a default pitch and power reflex setting like you suggest. A discussion worth reviewing.
This takes me to the question you might also be asking: why did not the crew make the informed decision, with their airspeed going awry, to methodically work through the Unreliable Air Speed (IIRC, section 8.110 in the FCOM, I may have that wrong) procedure. We'll never know why, as the two who could tell us that are dead. We can only guess, based on the evidence uncovered in the course of the investigation.
In re the stall: over the course of this three year discussion, it becomes apparent that most airline operators teach and preach stall avoidance, not stall recovery, which for the most part is a sound approach.
Ounce of prevention is well worth a pound of cure, and all that.
fustall
According to the report and about three years of discussion on this accident on these very forums, to include the ten threads now in the Tech log forum, the improvement to the Goodrich probes had been identified as a required fleet upgrade, and was underway. This was in response to an Airworthiness directive issued by a civil aviation authority.
This particular hull number had apparently not yet received the new probes at the time of the accident.
Why the upgrade was not pushed through sooner by Air France is certainly a question well asked. It is a question I do not doubt that lawyers for the 228 dead will ask in a court room somewhere.
If you dig through some of the informed discussion in the various threads, particularly the first four or five, in the Tech Log forum, you may find all the info you need to answer your question on the probes.
Cheers.
Based on the BEA report and the information released from the DFDR and CVR, the crew never grasped that they had stalled the aircraft. That would seem to be why they never put in stall recovery control inputs to unstall the aircraft. My estimation of that glaring error is that when they recognized that the airspeeds had gone awry, they made the assumption that stall warnings that they were receiving were spurious.
Can't prove it, however, so I am left guessing.
A more cogent question might be "why did they fly it into the stall?" I am not convinced that a 5 degree nose up pitch held ad infinitum would do other than slowly fly them into a stall, or slowly fly them to their service ceiling. (Or, that setting might have worked out just fine until the airspeed indicators became reliable again. Guessing, yet again. )
You will note from the BEA reports that the crew had already voiced their concern that temperatures at altitude did not suit their original plan to climb to FL 380 -- conditions had not progressed quite as forecast and they were concerned with that effect on aircraft performance.
A few threads ago, Clandestino, PJ2, and a few others went back and forth about the difference between pitch and power settings based on getting the charts and checklists out, and a default pitch and power reflex setting like you suggest. A discussion worth reviewing.
This takes me to the question you might also be asking: why did not the crew make the informed decision, with their airspeed going awry, to methodically work through the Unreliable Air Speed (IIRC, section 8.110 in the FCOM, I may have that wrong) procedure. We'll never know why, as the two who could tell us that are dead. We can only guess, based on the evidence uncovered in the course of the investigation.
In re the stall: over the course of this three year discussion, it becomes apparent that most airline operators teach and preach stall avoidance, not stall recovery, which for the most part is a sound approach.
Ounce of prevention is well worth a pound of cure, and all that.
fustall
Pitot tubes Icing,in this day and age it should be unheard of!
This was the start of the problem,how did Airbus get away with fitting inferior pitot tubes with inferior heating elements?
This was the start of the problem,how did Airbus get away with fitting inferior pitot tubes with inferior heating elements?
This particular hull number had apparently not yet received the new probes at the time of the accident.
Why the upgrade was not pushed through sooner by Air France is certainly a question well asked. It is a question I do not doubt that lawyers for the 228 dead will ask in a court room somewhere.
If you dig through some of the informed discussion in the various threads, particularly the first four or five, in the Tech Log forum, you may find all the info you need to answer your question on the probes.
Cheers.
Last edited by Lonewolf_50; 21st Sep 2012 at 12:41.
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Also I believe somewhere in the report it says the pitots were placed in an operating environment (eg ice accretion rate) which exceeded their design parameters, so not really AB's fault?
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Pretty funny. We're more than a thousand posts into this thread and people are posting stuff that was probably on page two. ("How could they stall????" "How could the pitots have iced???") Soon we'll be back to "They must have flown into a thunderstorm."
Reminds me of the Kee Bird, which flies in ever-decreasing circles until it finally flies up its own anus, only here the circles seem to be decreasing at a near-infinite rate.
Reminds me of the Kee Bird, which flies in ever-decreasing circles until it finally flies up its own anus, only here the circles seem to be decreasing at a near-infinite rate.
Last edited by stepwilk; 21st Sep 2012 at 12:50.
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This was the start of the problem,how did Airbus get away with fitting inferior pitot tubes with inferior heating elements?
According to the report and about three years of discussion on this accident on these very forums, to include the ten threads now in the Tech log forum, the improvement to the Goodrich probes had been identified as a required fleet upgrade, and was underway. This was in response to an Airworthiness directive issued by a civil aviation authority.
This particular hull number had apparently not yet received the new probes at the time of the accident.
Why the upgrade was not pushed through sooner by Air France is certainly a question well asked. It is a question I do not doubt that lawyers for the 228 dead will ask in a court room somewhere
This particular hull number had apparently not yet received the new probes at the time of the accident.
Why the upgrade was not pushed through sooner by Air France is certainly a question well asked. It is a question I do not doubt that lawyers for the 228 dead will ask in a court room somewhere
You explained why they made the change .....
I can be wrong but I think the meaning of the remark (or question) was "why Airbus (in the first place) fitted those particular brand and patent (Thales) Pitot tubes ? "
At the time of the original Pitots fitting on the A330 it was already better Pitot tubes on the market
To tell with your own words :
"It is a question I do not doubt that lawyers for the 228 dead will ask in a court room somewhere. "
Stepwilk
Pretty funny. We're more than a thousand posts into this thread and people are posting stuff that was probably on page two. ("How could they stall????" "How could the pitots have iced???") Soon we'll be back to "They must have flown into a thunderstorm."
It's a indication that we are circling and waiting permission to land in the court room
It's a long time to wait and I hope we will not be short of fuel !
Last edited by jcjeant; 21st Sep 2012 at 15:24.
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May have been said already,but don't start shooting down comments by possibly new people to the forum:get off your high horses all you oldies!!
I would expect some leeway from fellow Aviators and Non-Aviators alike
I like many others watched the CH4 documentary and was amazed that three professional pilots ignored 58 STALL warning's!!What....did they do basic flying or gliding?
Would they have survived a cable-break at 300' in a K13.......I doubt it!
Get the nose down..speed 55 knots minimum then and only then decide what you are going to do and choose a safe landing area.
Yes ..happened to me,first solo and I'm still here!
OK I've had my rant,another thought thou to give respect to the crew maybe they were not thinking straight,maybe the Ozone(O3) had a mental effect on the crew??
just a thought......Neeeeeooowwwwwww.......SPLAT!
Ok you shot me down
Effects of Ozone (0.30 Parts per Million, approximately 600 micro g /cu m) on Sedentary Men Representative of Airline Passengers and Cockpit Crewmembers.
I would expect some leeway from fellow Aviators and Non-Aviators alike
I like many others watched the CH4 documentary and was amazed that three professional pilots ignored 58 STALL warning's!!What....
did they do basic flying or gliding?Would they have survived a cable-break at 300' in a K13.......I doubt it!
Get the nose down..speed 55 knots minimum then and only then decide what you are going to do and choose a safe landing area.
Yes ..happened to me,first solo and I'm still here!
OK I've had my rant,another thought thou to give respect to the crew maybe they were not thinking straight,maybe the Ozone(O3) had a mental effect on the crew??
just a thought......Neeeeeooowwwwwww.......SPLAT!Ok you shot me down
Effects of Ozone (0.30 Parts per Million, approximately 600 micro g /cu m) on Sedentary Men Representative of Airline Passengers and Cockpit Crewmembers.
Last edited by fustall; 21st Sep 2012 at 18:26.
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You know, that is also not the first time this mythical bird has its appearance - it was called Oozlum, if I remember BOAC correctly. So now we have a circle which explains a circle in a circle. Time to get out!
was amazed that three professional pilots ignored 58 STALL warning's
Rather than "ignoring" a stall warning they were not aware of the fact that the aircraft was stalling - if they were they would have applied recovery action.
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The consensus seems to be that a tactile warning *might* theoretically help, but it's not a certainty.
"Stupid" isn't the right word. The issue is one of human psychology under pressure and how it can severely skew the decision-making process. See also: being so concerned about work-time regulations that you try to take off without clearance, committing to take-off despite disparate airspeed data, attempting to fudge an approach rather than turn around and try again etc.
Last edited by DozyWannabe; 21st Sep 2012 at 19:39.
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Quote:Rather than "ignoring" a stall warning they were not aware of the fact that the aircraft was stalling - if they were they would have applied recovery action.
Their Altimeters were working!and there Vertical speed indicators as far as I have read in the report,10,000 ft a minute come on these are three supposedly experienced crews!looking at the report they hardly had any training in stall warning or recovery
Too much computer flying experience rather than hands on experience IMO,computers/equipment fails....what do we do????
Their Altimeters were working!and there Vertical speed indicators as far as I have read in the report,10,000 ft a minute come on these are three supposedly experienced crews!looking at the report they hardly had any training in stall warning or recovery
Too much computer flying experience rather than hands on experience IMO,computers/equipment fails....what do we do????
Their Altimeters were working!and there Vertical speed indicators as far as I have read in the report
Having witnessed how quickly it is possible to be close to overwhelmed by events in the cockpit to some degree I'm with the "maxed out" theory and would certainly second fireflybob's comments that hearing is the first of the senses to "go" when you are overloaded. In order to really understand the reason for initial backstick and the subsequent response, or lack of, to the stall warning, we need to be able to know what the two pilots were perceiving throughout the onset of loss of control and subsequent stalled descent - trouble is we never will.
Dozy
"Stupid" isn't the right word. The issue is one of human psychology under pressure and how it can severely skew the decision-making process.
Last edited by wiggy; 22nd Sep 2012 at 20:38.
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wiggy
"In order to really understand the reason for initial backstick and the subsequent response, or lack of, to the stall warning, we need to be able to know what the two pilots were perceiving throughout the onset of loss of control and subsequent stalled descent - trouble is we never will."
I disagree, utterly. you would enlarge your understanding manifold once hearing evidence that is unfortunately unavailable to you, or to the public.
The CVR tells BEA everything, they tell us next to nothing. It is quite possible the CVR will find its way into the public domain. If available to you, would you listen? Or would you cover you ears, satisfied with a 'story'...
"In order to really understand the reason for initial backstick and the subsequent response, or lack of, to the stall warning, we need to be able to know what the two pilots were perceiving throughout the onset of loss of control and subsequent stalled descent - trouble is we never will."
I disagree, utterly. you would enlarge your understanding manifold once hearing evidence that is unfortunately unavailable to you, or to the public.
The CVR tells BEA everything, they tell us next to nothing. It is quite possible the CVR will find its way into the public domain. If available to you, would you listen? Or would you cover you ears, satisfied with a 'story'...