Hi HN39,
None as it is unrelated to ADR Machs.
Mach "selecté" or "selected Mach" is entered manually by the pilot in "selected" mode or managed by the FMA in "managed mode". Of course, one needs an autopilot working in order to use the flight guidance.
Consequently, this graph value represents the "Mach" targeted currently selected/used before autopilot kicked off.
Last change was at 0209:58 when "managed" mode was switched to "selected" mode, and pilots set it at Mach 0.80 (they were reducing targeted Mach). So before this point, Mach variations should have been automatically managed.

Looking at graphs pages 112-113, Mach_selecté is the blue straight line at M.80 (barely visible on the second one). The green value should be ADR_Mach_1 (as there is no ISIS_Mach). The blue blocks should be periods of flight in managed_Mach.
Mach_selecté do not move at all during the event like altitude_selectée ; the last one was rather the active mode (vertical)... hence, maybe this "je te mets sur ATT" would rather be "je te mets sur ALT".
But I'm not sure, I need to verify this last point.

3holelover:
How about:

Can it's stall really SOUND like an overspeed?

"Can it's stall really SOUND like an overspeed? ... If it did, that could certainly explain the confusion on the part of both the PNF and the Captain, but the PF?.... I have difficulty understanding how he could have interpreted motions and responses to his inputs as an overspeed vs a stall. ...even if it did sound that way.

Page 108 English version:

Why is the Capt sidestick shown as INOP from 2:14:20?

Did the FO side priority switch get pressed?

Or am I misunderstanding?

You are not mistaken at all. PF disabled PNF stick, using priority, during the last 10 seconds or so. Note that the last imputs from the PNF reverted also to nose down. The vast majority of his few imputs were ND anyway.

In an aircraft with unpowered controls, the pilot gets important tactile feedback re airspeed from how much force is required to move the controls. I doubt that an experienced Cessna pilot, for example, would mistake a stall for exceeding Vne in a light aircraft, even in the absence of external references or air data.

Obviously that's missing from this aircraft, although that begs the question of how control "feel" could be correctly added in the absence of reliable airspeed. Presumably Boeing has such an algorithm; whether or not it would have worked in this situation is beyond my ken.

But it does go to the problem of how far the pilot is separated from flying the airplane (as opposed to flying the computers) in 4th generation air transport aircraft.

Thank you Takata for your expanation about the flight directors.
I have been as all of us, appaled by the entire sequence of events.
I firmly beleive (and it has been said elsewhere) that the trim wheel and the THS staying at 13° until the crash is the key explanation to their not regaining control of the aircraft, but I keep wondering about the FD's. As you said, when reengaging, they take the altitude of the time as their new reference, and the horizontal bar will (with the plane diving down ) give an UP order to the pilot, who is trained to follow it.
They(the FDs) should have been switched off on both sides from the very moment when the loss of valid airspeed indications became clear to the pilots : emergency procedure on page 81.
Strangely (to me…they must have a good reason !) Airbus does not ask for the Fds to be switched off in their procedure « Stall Alarm » (page 64) when asking to set ,with TOGA, an attitude of 12.5 degrees (taking off) or 5 at altitude. In those cases, a different order by the horizontal bar could be misleading and unhelpful or confusing.
In fact they (the Fds) were not cut off, so the bars on the displays kept coming on, then off, and one wonders if the horizontal bar, which one is trained to following, was not one of the reasons the flying pilot kept pulling upwards ?

I think at that point they were in a total state of confusion which would challenge even the best Ace. I have slightly modified my view on the overspeed.
Consider the start when AP disconnect the PF made aggressive nose up. After only 4 secs stall warning comes on. He reduces his nose up a bit however continues his ascent to FL375. By that point he is in a nightmare having traded his velocity energy for altitude potential energy.

Why did PF nose up initially? It was accidental. No verbal announcement, no increase in thrust etc. At that it appears there is no reason for a climb. Only AP disconnect and speeds becoming invalid. No indication of overspeed or stall until 4 seconds into his aggressive zoom climb manouver.
If you look at PF verbal transcript he sounds IMHO like he is in shock. It takes him a long time to even acknowledge the climb despite PNF nagging him 3 times to get back down. IMHO he is not aware of his own stick input from the onset. IMHO he is in the medical terminology "altered" i.e. mentally impared perhaps due to shock. Epinephrine surge can do strange things to the body, cold sweat, tense muscle, max heart rate and max respiration, blood draws to core and you can look pale. If you have been in this state you know how it feels and it's not good. By contrast the PNF appears to be much more collected and even frustrated by PF lack of response.

What about loosing instantly 300 feet when IAS quit (speed related altimeter correction) ?

With respect, PJ2 is precisely on point. However, the focus of the investigation seems to be closing on Human Factors, and rightly so, if the Data released is accurate.

If this is too quick, then my apologies. The CVR shows at its very basic a lack of underdstanding of the Flight Path, and its stimuli, both human, and mechanical, (Electrical?).

The Human dynamic will eventually be broken down by Psychologists, Behavioural, Physiological, and probably Psychiatric. This seemingly dysfunctional mess after loss of Autoflight will be dissected, and rightly so.

First, and not least, is the SS. The SS is only lacking in 'performance' relative to its Human counterpart. There is no need for each Pilot to see his counterpart's stick, period. Not if CRM, and a strictly no nonsense environment is followed. That is how I see it. Does PJ2 agree?

Hi PJ2,
I disagree.
AB FBW Normal Law feels completely different to any conventional aircraft I've flow. (VC9, 707, 737, TriStar, 747-400).
Occasionally, I am still tempted to "pick up the wing drop" on the approach in gusty conditions. Unfortunately the FBW decides to pick up the wing itself and the roll rate is now faster than I wanted. Hence PIO.
The PF was handling Roll Direct in ALT LAW which he obviously found very difficult (from the recorded inputs). Meanwhile Pitch ALT Law is unknowingly trimming out the elevator load with the PF's errors in back stick commands. (They have lost the natural speed stability of the aircraft).

No conventional aircraft feels anything like AB FBW in ALT LAW.

Hi Bear
True if the trajectory is what you want. If it's not - then you have no idea if it's PF's inputs or CB activity throwing you around.

control "feel" and mach versus stall
 

For the subsonic wing shape you can "feel" buffet and "stiffening" of the stick at the critical mach, whether via artificial control stick mechanisms or just "in the seat of your pants". You can also have control reversal for the ailerons, as the shock waves are messing around with the pressures that normally result in roll right for right stick and vice versa. Some planes have a pronounced nose-down "tuck", and the only way out is to reduce power and deploy spoilers or speed brakes.

The average "heavy pilot" without military experience rarely sees this. Additionally, the military planes usually have a greater structural margin per the design specification. So we could "push the envelope" in a way you would never try in a heavy. I only exceeded the Vne once, but the jet was robust and my biggest clue was that with a great amount of back stick the thing was not moving as much as I expected. Glanced at the airspeed and sure enough, I was 40 or 50 knots above the placard ) gotta admit that I was pulling off a heavily defended target and was getting hosed down big time by bad guys). You can't do that in a modern airliner, that is, gradually recover from the overspeed without ripping the wings off.

As Doze and others have repeatedly stated, most military and commercial heavies have not had the traditional control "feel" since the 50's. Move the hydraulic valve with the stick/yoke and the pressures went to the control actuators. Clever engineers used feedback devices to "stiffen" the controls at high "q" and to limit the control movement, while providing a sense of the Cessna/Champ/Cub "feel". Big deal.

Comparing control "feel" with the military FBW systems is not fair. We flew at AoA's and speeds and gees not applicable to the heavies. We flew by our own "feel", and the FBW confusers allowed us to ask the jet to do as much as it could without being too worried about stalling or exceeding the structural limits.

One way to "help" the pilots with the FBW system is to employ some of the PC game technology and have forces applied to the controls according to the flight conditions. In other words, use actual pressures detected upon the control surfaces themselves to be "felt" by the pilots. Can also use basic air data like dynamic pressure as a baseline - go fast, stiff stick, slow down and get sloppy and need more control displacement.

enuf war stories, and I continue to read the report again and again, as well as the neat posts here.

Bear :ok:

rudderrat

How do. It is especially important in emergency situations that the "other stick" be unavailable, visually. It is a distraction, a potentially lethal one.

If things are bad enough in the cockpit to doubt your counterpart's actions, it is CRM that must rule, not a "second guessing" that is a detriment to one's own responsibilities. Everything up to the simultaneous (and Dangerous) actions was defensible, from a command standpoint. Imo.

I might be wrong, but at this point I believe it might have been Airbus' purpose to isolate the two sticks, and if so, I can see why? Only one can LEAD, and only one can CONTROL, at any given time. It is at the point where these separate functions start to "Blend", that Satan starts to grin?

in an ideal piloting environment I could perhaps be persuaded.

But when humans are involved, errors will happen.

PNF may have clued in had he seen his ss sitting on the back stop.

My underlying concern is that when stuff goes wrong, good information is needed for the crew to put things right.

Among other factors, ss position and some red on the altitude/VSI display might have alerted PNF even though it seems he was too nice a guy.

PNF does not seem to have had any positive ideas about what needed to be done -- nor did CDB.

Q regarding language:
 

Forgive my ignorance of French please, but is there different language used in French for "Pitching" up/down vs "climbing/descending"? The use of phrases such as "you're going up" and "you're going down", sounds (in the transcript) to me to have added to confusion.

Pj2;
There is a difference in FBW in the busses... The "feel" in your hand is simply spring pressure which won't change at all with speed, whereas in older, hydraulic and cable beasts, the control column and cables would actually change the force required to move them with speed. (through the "trim, feel and centering mechanisms") ...and I think (but can't seem to locate my books at the moment) still in the 777, while being the same FBW style electron flow output, the force req'd at the column is adjusted with speed... somehow (damn, where are those books!) force xducers(?) -or is it the backdrive actuators? (I can't remember, dangit. ...maybe I'm wrong about that :hmm:)

In any case.... none of that changes how a human pilot would "feel" the changes in g acting on his body from his actions during a stall vs during an overspeed.

RatherBeFlying...

Do you see how "Two Pilots-One Stick" is a recipe for disaster? Take your own, only. It is not an instruction flight. "What's he Doing?" Is as Lethal as "What's it doing?"

This is not......"Francois, follow me through...."

3hl....

Again, in defense of IMC, feel is not necessarily desirable. It would seem, in a very real way, that PF may have allowed his own kinesthetics to drive his decisions? And to the contribution of LOC? Can we entertain a new descriptive? "Loss and MAINTENANCE of LOSS of control" ? Feedback is in some way an enemy of Instrument flight? If there is a total breakdown of systerms, well, ok, but that isn't happeneing here? If, in an emergency, a pilot has ONLY feel, well, ok, but otherwise there is a definite lack of engineered blend of seat of pants/FCS "Co-Operation"? More's the Pity? Will there need be hardwired ButtCheeks?

Well, not sure that would help a dime once suffering UAS.... or stalled and doing 170knots at FL380... next we'll be suggesting alternate gains that come into play. It gets complicated doesn't it?

I have mentioned that before.

This accident wouldn't have happened in e.g. 727 just of the feeling on the elevator.

AND

it would not have happened with a reliable stall warning, stickshaker/- pusher.

AIRBUS, where is your extraordinary sience?

A bungee for monkeys?

Altitude drop, roll, turbulence right before AP disconnect.
 

xcitation,

I've asked the question myself, and have contemplated several speculative explanatory scenarios, due to the limited official information at the time. I've posted one of the scenarios a week, or two, before the BEA report was made available. The posted scenario was that at AP disconnect, the AP was in the process of responding to a drop in altutude, and roll due to heavier turbulence, which was interrupted by the AP disconnect. So the PF reaction was to continue the AP's action with NU, and roll.

The BEA Report made available recently brings more information.
The graphs at the end of the document seem to provide several concurring elements to support the scenario I've considered:

1. there is a slight altitude drop on the Altitude graph, right before the AP disconnect - see page 108 of the English version of the report. The drop is very small, and it's hard to tell how much it is - maybe around 100 ft or so - as the graphs scale corresponds to 35000 ft or so, but Zooming IN, helps seeing it a bit better, within the limits of the graph resolution, and scale.
The altitude drop coincides with a reduction in thrust - see the N1 Actual Eng1% and Eng2 % graphs - and increased roll - see Roll graph.

2. the Normal Acceleration graph, which if I understand correctlty is a reflection of the Turbulence, shows increased up/down air turbulence activity right at that time.

So, I think, turbulence, drop in altitude (with reduced thrust) and roll, were the factors that the PF was responding too with Roll and NU.

I have a vague recollection of seeing posts tangentially, or directly mentioning the same thing, but can't recall exactly which ones.

PJ2
 

Well said. Much food for thought - enough to write a book, rather than a post, on current automation, the human/machine interface and line pilot airmanship standards/training. As you say re: FCOM......

Not the time/place for F/Os 32 & 37 to suddenly do their FLT350 hand flying training, under AB alternate law in UAS conditions in that part of the circadian rhythm over the ITCZ, but the CRM shortcomings now disclosed really didn't help matters. The PF tossed his coin, called heads (overspeed) rather than tails (stall), the PNF missed his opportunity early on to reach the right conclusion (I don't like the entire SS concept, but that's my prejudices and I won't impose them upon others) and the CPT never appeared to remotely catch-up with his plane in the apparent absence of any meaningful coherent reporting from his co-pilots as to what had already transpired.

All very sad, over in minutes, but a very long time being made by the industry......

Third time, first timer,


It was already said by the BEA, there was nothing wrong with the plane and IMHO the same can't be said about the PF. I was under the impression (and for more than two years) until reading the third interim report by the BEA in English, that the younger co-pilot (relief pilot) was the PF. But it never added up completely because, why experience didn't prevail? It did. Also, I couldn't understand why the most experienced co-pilot was screaming for the Captain to return? He didn't, it was the younger one and PNF. It is funny (Life likes that) that the Captain asked if the co-pilot (First Officer) had a pilot license online. This was omitted in the Interim Report #3 for some reason, I think, I can't find it.


FO: But I’ve been at maxi
nose-up for a while = He has been wrong far too long.
Cap: No no no don’t climb = Right but too late. Around under 4000 ft to impact too late.

Relief Pilot: So go down = Yes, but too late and not for long.

I got the complete picture now. I do not see how can we find the mark of a pilot before he/she goes under a real fire event. All the bells, whistles and gadgets won't work if no one pays attention to them or worst yet, decides to disregard them. :ugh:

VGCM66
 

You were correct first time. F/O 32 was PF in the RHS throughout. F/O 37 replaced the CPT in the LHS. F/O 37 had been resting (dozing) until not that long before the incident, which may partly explain his initial failure to get on top of the matter (UAS SOPs etc). Back to PJ2 - sitting for hours monitoring systems and then the speed of this emergency requiring instant quality hand flying airmanship skills (why the particular pitot tube model problem should have demanded a more urgent response, given the modern "hand flying" training and operating environment, given the history from Stony Point via Birgenair and Aeroperu)....

So the youngster got a hold of the SS and from then on the FO was reluctant to take it back away from him until the very end? In both scenarios it seems that the FO dropped the ball (no assertion). It doesn't make sense from his shoes. So, he was the one screaming for the Captain to return? And the Captain before leaving said at one point: He (FO) will take my place? If so, that kind of place him in charge, doesn't it?

What an innocent mess? :ugh:

Basic flight instruction and training
 

I know this is simplistic, but I'm not sure many here are aware of some of these fundamentals.
Knowing what to do and demonstrating that you can do it are two different things.
BASIC FLIGHT INSTRUCTION AND TRAINING
SIMULATOR AND FLIGHT TRAINING
I think there is a basic mis-understanding of what flight training is all about.
Following a pilot's initial training in any aircraft, in upgrading to a commercial airplane there is a series of stages. From basic flight to specific maneuvers visually and under instruments.
Assume the basics are known and understood. Push forward go down, pull back go up etc.
Whenever a training/simulator session is set up, the rules are understood. Altitude: 100 feet plus or minus. Heading: plus or minus 10 degree. Airspeed: plus or minus 10 kts.
Whatever procedure is being attempted, these criteria must be adhered to. It requires extreme focus, and development of feel and touch.
In dealing with an emergency, whether a fire, loss of engine or anything less, it then requires coordination to handle each one. If the pilot flying tries to deal with the procedure, it is not possible to read and follow the checklist at the same time.
The proper protocol is to hand off the flying to the other pilot who is them responsible for keeping the plane under the foregoing limits, while the pilot reading the checklists assures that each component complies.
But well before this, while knowing what these limit critieria are, a pilot must be able to demonstrate a capability of doing so.
Knowing what the plane can/should do is different than doing it and demonstrating it.
Without ever handling a plane/simulator it is not possible to accomplish any of this the first time out. Let alone in a real life situation, with turbulence and stress.
Here, with many different laws and conditions without hands on training in each phase, successful flight is literally impossible, as we are seeing in this last 4 minutes.

VGCM66
 

CDB even had to check, when he switched with the dozing F/O 37, that F/O 32 was qualified to implicitly take command as the PF (and had been the PF from GIG). Given my vintage, don't even get me started on reinforced crews issues (2 CDBs and 1 F/O, not vice versa!). But save only for the ITCZ (and the CMB that triggered the disaster through the pitot tube failure), it should have been an uneventful systems monitoring leg of the oceanic transit. F/O 37 had not been placed in command as the more "senior" of the two F/Os, and the BEA are criticial of the lack of designated roles for F/O 32 & F/O 37 before CDB departed for his rest break, and note F/O 37's concern at the delays in CDB returning to the cockpit (F/O 37's actions, or lack thereof, are likely to feature further in the final report - psychologists/behaviourists etc).....

3holelover:
Pitching up is "cabrer".

The PF uses this, at one point:
2 h 13 min 40
PF: Mais je suis à fond à cabrer depuis tout à l’heure
But I'm nose up to the limit since earlier

And then again 2:14:05.

Pitching nose down would be "piquer"

It also struck me how (with the few exceptions just noted), neither PF nor PNF, nor the CDB once he returns, ever speaks of pitching up or pitching down. They constantly speak of going up and going down.

A33Zab-- Selected vertical speed? (Post #1497)
 

I've deleted this post as I misinterpreted the selected vertical speed (green line) to be intermittant commands in the A/C computer, whereas they are intermittent sampling of commands having continuous effect (as I interpret takata's comments below). I'm leaving this line so as to not change all the following post numbers. --OE

I thought the Airbus side stick was simply spring-loaded to neutral. I would not call that an artificial feel.

An a/c with mechanical controls sends back two qualitative messages to its pilot as regards the pitch axis.
1/ speed: whether you are fast or slow, the stick is stiff or limp.
2/ trim: the residual force on stick required to maintain an attitude tells you where you are relative to you trim speed
I believe an Airbus side stick conveys neither speed (C* law) nor trim (autotrim). Or did I missed something ?

Hi VGCM66,
One day, considering that final BEA report will not be published before next year (1st semester 2012), we'll have to make a FAQ about this thread for "First Timers" who seems to be lost in BEA reports translation... but, believe me, I understand perfectly the issue.

So, lets go for one more explanation:

1. "Relief" pilot, in Air France terminology, means "co-pilot (F/O) acting as Captain"; hence, he is the pilot in charge (PIC) when the captain is resting. It is not the same meaning than "limited duty officer", for "relief" at cruise, like many other companies are calling it.

2. Air France longhaul crews are composed of the "commandant de bord" (captain) and two fully qualified co-pilots (F/Os) having the exact same rank (whatever their age).

3. When captain is leaving the deck, he should decide whilch one of his two F/Os will be the pilot in charge (PIC) during his rest.

4. The officer designated as PIC must be the pilot flying (PF) during his rest. (this part was changed after AF447)

Consequently:
AF447 used this system and when Captain (no name please) took his rest:
- Pilot Flying (PF), being the pilot in charge (PIC), was the 32 years old F/O and was seated in RHS (Co-pilot seat in CVR/DFDR table).
- Pilot Non Flying (PNF) was the 37 years old F/O and was seated in LHS (Captain seat in CVR/DFDR table)

Quite disturbing, isn't it?
:O
All along this thread, we are refering to the, Captain, PF (RHS) and PNF (LHS) as at 02:10UTC. But at some point, PNF could be the one flying the aircraft !

takata
 

Your post should be mandatory for all new joiners to the thread.

As regards your question, you may imply that but I could not possibly comment......

Old Engineer . . .
 

I don't think we can deduce much from the given fractional positions of the stick. It could just as well have been given as a percentage or in another base. The stick position will have been converted to a voltage, and the voltage then digitized, for input into the computer, perhaps with some cleanup along the way, before being recorded on the FDR. The fractional notation is for ease of digestion by the reader.

Sampling rates are another issue. Could be anything, from the rate you suggest to some artifact of processing the data. The sampling rate, recorded stick position, and other recorded data are chosen for logical reasons, and would not be limited by the speed of the computer.

Perhaps SensorVal or others would care to elaborate.

Bear: I've called out altitudes in a descent as an alert to a PF more than once. Tone of voice will vary with situation.
Indeed, he may have been thinking that, but as I noted above, had to deal with the denial phase of a pear-shaped situation. He went about other tasks, as there were plenty to choose from, or so it may have appeared to him.
The fellow in the RHS seems to have done most of that, even with Monsieur Robert nagging him about his nose attitude. Somewhere in this discussion, I see some ideas that even after the control change, you had two people trying to move the control stick. That isn't good. :(
I mentioned that to Dozy when he first brought it up. I agree with you on that.
Is he saying "Way Fast" with no airspeed indication? Disorientation, evidence of.
Why is static reading high? Ice, or something else?

Smilin' Ed: OK, I see where you are coming from.

Machinbird: That may be true, but I don't think A330 was designed with "extreme flying" in mind. ;)
Food for thought.

BOAC If nothing else was working, revert to basics. I might have done the same, if I didn't realize I was stalled. Try something, anything.
One hopes not.
Food for thought.

PNF seemed perfectly well "clued in" when it all started to go wrong - he knew PF was over controlling roll and chastised him for it, he knew PF was climbing when he shouldn't have been. In fact PF is the one who seemed unaware of what he was doing with his own SS.

None of them seem to have recognised stall, even when the warning was continuous, no recovery is ever discussed or actioned. With the possible exception of TOGA - not sure about that, I almost get the sense that PF is saying "can't be stalled, I'm in TOGA", but can't be sure (anyone else read it that way ?). In fact looks like PF thinks he's over speed if anything.

Captain I feel sorry for, he comes back in to stall warnings, AOA already so high that instrument data is going haywire left right and centre, no visual reference, and he has to work out what's happened without any info other than "we lost it". He has only 2 mins to diagnose stall and have the confidence to order 30deg or more nose down to attempt a recovery. I don't think hereally had a chance to save it from then.

I get more and more confused. Could we agree whether the following was true?

1. The officer who was resting prior to 2am was F/O 37.

2. The officer who 'wasn't sleepy' was F/O 32, who has also been PF from Rio.

3. The Captain woke F/O 37 and said (to F/O 32) that the older officer was to 'take my place'. By this he meant F/O 37 was to sit in the LHS, not to be PIC.

4. The Captain asked F/O 32 if he was certified, presumably to be PIC from the RHS. Presumably this question had not arisen on the outward leg.

Very important point. So...

AP disconnects
a/c at 0 deg pitch => will descend
pilot stick back 3/4 causing nose up pitch 11 deg.
climb rate goes up.
after 4 seconds first stall warning
after 15 seconds altitude has not changed (downdraft/reduced thrust?)

So PF was correct to stick back but he over does it.
Stall alarm sounds, he eases off on the stick pushes it fwd briefly, alarm stops.
Then he resumes stick back to maintain altitude.
Now the THS starts helping PF to pitch nose up.
Now he is gaining altitude with help from THS.

Report #3, Page 111, Longitudinal parameters

Notice the insidious influence the auto THS (cyan) has on elevator position. At some points he is stick forwards (red line, 02:12:17) yet elevators stay around -30 deg (purple). Clearly this would add to the confusion of inputs.

Thanks Spagiola. Using those phrases ("going up"/"going down") sure seems to hinder understanding.

overthewing
 

Yes, save for your final sentence under (4). This was not the same crew that had flown out, if my memory serves me well (e.g. PF had been on holiday with his wife, without their children, on board the flight).

I've had some complaints regarding French translations and offensive text. Not being a French speaker, I am a bit out of my depth with such problems as, to quote the saying, "it's all French to me".

If you have a problem with French text as posted, by all means send me a PM with details.

Due to the present day job workload, I am a little behind in my monitoring of this thread. I expect to catch up in the next few days.