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There is one part of the narrative that says they reduced speed immediately after disconnect, how did they do that?
They reduced speed immediately prior to disconnect. They did this by selecting .80M on the FCU. When the autothrust disconnected, the power levels had decreased from 100% N1 and were locked in at 83% N1, far too low for a climb attitude at that altitude and weight. While they increased pitch and began to climb, they did nothing to increase the power level for 23 seconds. When the PIC noticed the situation, he told the PF to move the thrust levers to disengage thrust lock and power was increased at that point.
The ECAM was displaying the message "MOVE THRUST LEVERS" during the 23 second sequence.
I think this message should be displayed on the PFD as well.
Correction, they were doing things but were hesitant and perplexed (or so it seemed), they did nothing that seemed to work.
Sorry. They pushed a bit and pulled a bit and turned a bit.
There is one part of the narrative that says they reduced speed immediately after disconnect, how did they do that?
They clearly pulled up to bring the plane in that skyrocketing initial climb.
That was the major contributor to the loss of speed. And then, when the stall announced that they were about to stall, they pulled up again. That had nothing to do with external factors such as vertical air currents. It was all commanded from the sidestick.
--- Judge what is said by the merits of what is said, not by the credentials of who said it. ---
--- Defend what you say with arguments, not by imposing your credentials ---
Gabriel, steer me in the proper direction but I get lost at a few points here which is quite apparent. (slap forehead)
You mention a skyrocket climb and this is where I get confused. True, there is a gain of 2,500 feet but is it perhaps over about 4 minutes since they are said to be at 35,000 at 2-6-4 and then are reported to be at 37,500 at the 2-10-5 mark. There is a reported and marked drop in airspeed from 275 dropping down to 60 knots at about that time and it seems obvious but that is where I have a problem since the events in the report are cut down into for lack a better word, "blocks of time", they are not precise in how they are reported so when I go back over that did they loose it and do a sudden "zoom climb" or perhaps did they creep up, drift up or whatever over about 4 minutes, the latter is not that dramatic. There is also the comment that the PF is doing some push down left and push down right on the stick.
What also makes it difficult is that with them using terms like "pilot flying" since they have indicated that they alternate without communication, I am having a hard time visualizing who is doing what.
I read that sequence and can see how you arrive at that but with the reporting sequences in these "chunks", I would be reluctant to use the word "clearly".
Looking at that change in speed, it is highly likely .. ??
Gabriel, steer me in the proper direction but I get lost at a few points here which is quite apparent. (slap forehead)
You mention a skyrocket climb and this is where I get confused. True, there is a gain of 2,500 feet but is it perhaps over about 4 minutes since they are said to be at 35,000 at 2-6-4 and then are reported to be at 37,500 at the 2-10-5 mark. There is a reported and marked drop in airspeed from 275 dropping down to 60 knots at about that time and it seems obvious but that is where I have a problem since the events in the report are cut down into for lack a better word, "blocks of time", they are not precise in how they are reported so when I go back over that did they loose it and do a sudden "zoom climb" or perhaps did they creep up, drift up or whatever over about 4 minutes, the latter is not that dramatic. There is also the comment that the PF is doing some push down left and push down right on the stick.
What also makes it difficult is that with them using terms like "pilot flying" since they have indicated that they alternate without communication, I am having a hard time visualizing who is doing what.
I read that sequence and can see how you arrive at that but with the reporting sequences in these "chunks", I would be reluctant to use the word "clearly".
Looking at that change in speed, it is highly likely .. ??
And through all this, according to the CVR, there is no mention of the word stall in the recording. Further, there is almost not a word said by the Captain upon returning to the cockpit from his rest break. Was the Captain in a complete state of shock of what was happening...?
Gabriel, steer me in the proper direction but I get lost at a few points here which is quite apparent. (slap forehead)
You mention a skyrocket climb and this is where I get confused. True, there is a gain of 2,500 feet but is it perhaps over about 4 minutes since they are said to be at 35,000 at 2-6-4 and then are reported to be at 37,500 at the 2-10-5 mark. There is a reported and marked drop in airspeed from 275 dropping down to 60 knots at about that time and it seems obvious but that is where I have a problem since the events in the report are cut down into for lack a better word, "blocks of time", they are not precise in how they are reported so when I go back over that did they loose it and do a sudden "zoom climb" or perhaps did they creep up, drift up or whatever over about 4 minutes, the latter is not that dramatic. There is also the comment that the PF is doing some push down left and push down right on the stick.
What also makes it difficult is that with them using terms like "pilot flying" since they have indicated that they alternate without communication, I am having a hard time visualizing who is doing what.
I read that sequence and can see how you arrive at that but with the reporting sequences in these "chunks", I would be reluctant to use the word "clearly".
Looking at that change in speed, it is highly likely .. ??
I was writing my usual long explanation, but I guess that an image is worth a thousand words.
--- Judge what is said by the merits of what is said, not by the credentials of who said it. ---
--- Defend what you say with arguments, not by imposing your credentials ---
And through all this, according to the CVR, there is no mention of the word stall in the recording. Further, there is almost not a word said by the Captain upon returning to the cockpit from his rest break. Was the Captain in a complete state of shock of what was happening...?
I think one interpretation of the conversation would certainly have to be that, once stalled, no one understood that was the case. It seems that the pilot flying was intent on making sure they had plenty of thrust with the nose pointed up, which, in his mind, should have caused them to climb... he didn't understand why they continued to fall:
"What is… how come we’re continuing to go right down now?"
Then later, when the captain was advising against pitching up, the PF was insistent, saying "Well we need to we are at 4000 feet." He still wanted to use a combination of thrust and a nose-up attitude in order to climb.
The captain, upon entering the cockpit, asked what was happening, to which the answer basically was "I don't know", and he was unable to interpret what he saw, either. His focus seemed to be on keeping the wings of the aircraft level, and again he seemed unaware of the rate of descent, or perhaps not trusting the altimeter.
Two seconds after the pilot flying asks for the altitude, the captain says, "That's impossible..." which may or may not be in reference to the question. But it doesn't seem like he wants to avoid pitching up in order to increase speed or recover from a stall, he simply doesn't want to climb. Only when the automated warning said "Pull up" did the captain decide they should pull up, again, with the mistaken idea that they would gain altitude if they did so.
Then there was that whole confusing exchange of:
PNF You're climbing...you're going down down down
PF Am I going down now?
PNF Go down.
Capt. No you climb there.
PF I'm climbing ok, so we're going down.
To me, it just seems that there's a fundamental confusion, and perhaps disbelief, about how it is they're losing altitude while pointing nose-up with thrust.
I insist. Stop putting so much attention on what happened so late during the chain of events. They botched they unstabilized the plane with a violent climb after the autopilot gave up, then they botched the approach to stall by pulling way up, and then the initial recovery of the fully developed stall by holding nose-up input. After that, everything was hopeless, not bacause the plane could still be recovered (thing that I don't know) but because it's not expectable that a crew that managed to do all these things so wrong suddenly becomes the best crew in the world.
About: "Well we need to we are at 4000 feet." They were at 4000ft falling 10000 ft/min. They had only 20 seconds. At that point holding full nose-down input was not going to be any better (or any worse) than keeping the nose up. It's up there where they should have done it, well before the AoA passed through the 40° mark (which a ridicously high AoA where no plane is expected to operate ever, not even in emergencies, and thus it's not designed to operate there, not flight tested there, and not required to recover from that).
Note this: the 40° AoA mark was passed when the plane still was at 35000 ft (going down from 38000), one minute of continous stall warning had passed, the pilot was still mainly pulling up, and at that point the stall warning stops (due to the airspeed readings going all below 60kts). Since a useful recovery attempt had not begun up to then, I propose that that's the last point of the "useful" analisys.
--- Judge what is said by the merits of what is said, not by the credentials of who said it. ---
--- Defend what you say with arguments, not by imposing your credentials ---
I insist. Stop putting so much attention on what happened so late during the chain of events. They botched they unstabilized the plane with a violent climb after the autopilot gave up, then they botched the approach to stall by pulling way up, and then the initial recovery of the fully developed stall by holding nose-up input. After that, everything was hopeless, not bacause the plane could still be recovered (thing that I don't know) but because it's not expectable that a crew that managed to do all these things so wrong suddenly becomes the best crew in the world.
about: "Well we need to we are at 4000 feet." They were at 4000ft falling 10000 ft/min. They had only 20 seconds. At that point holding full nose-down input was not going to be any better (or any worse) than keeping the nose up. It's up there where they should have done it, well before the AoA passed through the 40° mark (which a ridicously high AoA where no plane is expected to operate ever, not even in emergencies, and thus it's not designed to operate there, not flight tested there, and not required to recover from that).
Note this: the 40° AoA mark was passed when the plane still was at 35000 ft (going down from 38000), one minute of continous stall warning had passed, the pilot was still mainly pulling up, and at that point the stall warning stops (due to the airspeed readings going all below 60kts). Since a useful recovery attempt had not begun up to then, I propose that that's the last point of the "useful" analisys.
I understand all of that. My point is that they never knew they had stalled the plane, and that's reflected by the entirety of the dialogue right up to the end.
Perhaps what is needed is a "in stall" announcement. The existing "stall" warning is an approach to stall signal for the pilots, before a stall actually occurs, but there is no aural announcement to let them know when the aircraft is no longer flying, so to speak. If such a warning existed, the pilots might have used the abundance of altitude to get the nose down, keep it down, and build back airspeed to lower AoA and regain lift. (This assumes a modicum of basic airmanship). Apparently they missed the stall buffet and the roll instability. Perhaps the having static spiral stability now at 0° masks that somewhat?
So why isn't there a "congratulations, you are now stalled" announcement?
Perhaps what is needed is a "in stall" announcement. The existing "stall" warning is an approach to stall signal for the pilots, before a stall actually occurs, but there is no aural announcement to let them know when the aircraft is no longer flying, so to speak. If such a warning existed, the pilots might have used the abundance of altitude to get the nose down, keep it down, and build back airspeed to lower AoA and regain lift. (This assumes a modicum of basic airmanship). Apparently they missed the stall buffet and the roll instability. Perhaps the having static spiral stability now at 0° masks that somewhat?
So why isn't there a "congratulations, you are now stalled" announcement?
You are kidding, right?
The stall warning is already saying "you are at a too high, dangerously close to stall, unauthorized AoA. (and I'd would not let you fly like this if I had normal law authority). Reduce AoA now".
--- Judge what is said by the merits of what is said, not by the credentials of who said it. ---
--- Defend what you say with arguments, not by imposing your credentials ---
I understand all of that. My point is that they never knew they had stalled the plane, and that's reflected by the entirety of the dialogue right up to the end.
Again, if the buffet and the combination of a 16° nose-up pitch with a 10,000fpm sink rate was not enough of a clue, surely a synthetized voice shauting "stall, stall, stall!!!" uniterruptedly for one full minute must have been. Unless they, like MCM, thought that a wrong low speed reading can trigger a false stall warnig.
--- Judge what is said by the merits of what is said, not by the credentials of who said it. ---
--- Defend what you say with arguments, not by imposing your credentials ---
You are kidding, right?
The stall warning is already saying "you are at a too high, dangerously close to stall, unauthorized AoA. (and I'd would not let you fly like this if I had normal law authority). Reduce AoA now".
No, I'm serious. It's just another aspect of situational awareness. If they think they are 2-3° below actual stall, they may try to fly the plane in a way that it can't be flown in a fully developed stall. I'm not disagreeing that the stall warning should be enough, but it clearly isn't. They didn't seem to think they were actually in a stall despite the stall warning, so I assume that they thought they still had adequate lift and authority and they tried to fly out of what they thought was approach to stall, using TOGA thrust and tried to arrest sink rate using variations in pitch. Yes, it's the wrong thing to do, but would they have even tried this if they knew they were in a developed stall? Or would they have seen the futility of that and pushed the nose over to try to get it flying again? I think knowing they were not flying and they weren't going to simply power out of the situation could have made a difference, despite their obvious lack of understanding re: approach to stall procedure. I think maybe they would have been less reluctant to give up altitude for airspeed at that point.
I mean the secondary problem, after getting the thing into trouble in the first place, seems to have been flawed situational awareness.
Again, if the buffet and the combination of a 16° nose-up pitch with a 10,000fpm sink rate was not enough of a clue, surely a synthetized voice shauting "stall, stall, stall!!!" uniterruptedly for one full minute must have been. Unless they, like MCM, thought that a wrong low speed reading can trigger a false stall warnig.
I'm just telling you what it sounds like to me when I read the transcript. For whatever reason, they don't put it together that they are in free fall. They are trying to control the roll and monitoring the thrust, and they are definitely aware that something is seriously not right (attributing it at one point to "some crazy speed") but they don't seem to get why they are losing altitude. Variously -
"But we've got the engines what's happening?" (PNF)
"What's happening? I don't know what's happening?" (PNF)
"What do you think about it? What do you think? What do we need to do?" (PNF)
I don't think I'm going too far out on a limb by suggesting the pilots don't know what's going on, including the fact that they're fully stalled.
Planes have a thing called an attitude indicator- and that pilots use this instrument a lot.
The attitude indicator was working on the Air France plane.
I have also heard that pointing the nose up- especially at a high altitude where the air is thin and there's less power, is a reasonably good way to stall a plane.
Nose up, high altitude, stall warning....naw.....it's not a stall scenario, keep hauling back on the side stick.
Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.
Planes have a thing called an attitude indicator- and that pilots use this instrument a lot.
The attitude indicator was working on the Air France plane.
I have also heard that pointing the nose up- especially at a high altitude where the air is thin and there's less power, is a reasonably good way to stall a plane.
Nose up, high altitude, stall warning....naw.....it's not a stall scenario, keep hauling back on the side stick.
That's true, I didn't say they shouldn't have known they were stalled, I'm just saying they didn't. Once you get over the fact the pilots were out of their league, you still want to try to figure out what they might have been thinking.
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