Erm, that is true. However, are there unintended side effects such as premature finger pointing?

If the data gets altered those altering it face a problem. Secrets are not normally very well held, especially in this age of Wikileaks. There are enough people watching the physical hardware containing the data and the extraction of the data that pushing out forged data will be a very high risk behavior.

Wallybird, if I may brag a little in turn, when I left college and entered industry I had experience far beyond that of the usual graduate. (Which seemed to piss off some of my peers no end.) I entered industry as an electronics engineer in the communications electronics field with an MS degree. I had already been designing and modifying radios for over a decade on my own. I had a very good idea what those silly little electrons I was pushing around could do.

I continued to learn. And I pushed around ever larger batches of electrons. (Then I literally got bored and moved over into the software realm - partly by "long story" accident.)

And I was an exception with two things in my favor, the self taught experience I had and a strong affinity for communications electronics and software. I was emotionally committed to my job.

It sounds like you were to. And I hope you have continued to learn. I presume you are not quite so naive today as you were straight out of your first flight training. And maybe you've learned some practical things about what you're flying now that were not taught in any schools.

However, there is evidence on the ground that people who are not highly committed to their job, in love with it as it were, who get into pilot training and somehow come out the other end with their piece of paper entitling them to be a member of a transport aircraft's cockpit crew. Just off hand 9/11 comes to mind right off.

I am very distrustful of somebody who comes out of training of any sort as a know it all or thinking he knows it all. Generally they don't. And their overconfidence, their hubris, can lead to a fall. (It is not inconceivable something on the CVR that has been released may implicate PF of having a fatal case of hubris.

I had the good sense, when I hit industry, to realize I knew a lot, had a near intuitive feel for what electrons would do, and anticipated I still had a things to learn that would be fun having learned them. (I admit to bitching about the learning process.)

We got in a low speed buffet in an MD 80 when my captain decided to get clear of turbulence by climbing faster seeing the blue sky above in the clouds and his speed got slow. I told him he was too slow so he hit alt. hold at 365 climbing to 370 but it was too late and even with max power we couldn't get out of it. I told center we needed a lower now but we had opposite direction traffic 12 oclock 5 miles so they couldn't clear us lower. The opposite direction traffic was at 350 1500 ft below us so we never had legal separation back then in the 80's. We selected 500 fpm descent to keep from going into a deep stall with the plane buffeting even with the 500 fpm descent. I figured we needed 20 seconds to pass him in the clouds so once we were clear ATC let us continue our descent to got full control back.

I hope when the final reports come out we will understand what made the PF think he had to pull back instead of push forward. If we had pulled back we knew what the results would be. A deep stall and total loss of control. I am not proud of what we did that day because that is the only time in my life I felt out of control of our aircraft because we weren't paying close enough attention. It never happened again and that was over 15,000 hrs ago.

Thanks PJ2,

I would suspect the -80E would be similar.

I would think the CFM's on the A-340 would be working very hard at Mach 0.83 and 35K, pushing the edge of their capability, could have used a slightly larger fan along with an additional LPT stage with more modern airfoil aerodynamic efficiencies that are now available.

S_Ed, (#1581) I don’t know, but your question could be added, or even associated with these:- http://www.pprune.org/tech-log/45283...ml#post6492274 #1305

And what about the IRU aspects too?

PAX in75, '68'

Tactile feedback
 

MurphyWasRight and others, I'd propose a tactile feedback to the other side from that which last pressed the I've got it button. Then the PNF can feel what is going on. Once he takes over there's either no feedback (which should be the fail safe condition) or there is simple stiffness feedback as gums seems to say existed in military aircraft.

Tactile feedback
 

JD-EE:

In normal situations the 'feedback' will be noticed by PNF.
If PF SS input is 1G climb (ANU), PNF will experience a 1G climb and knows PF pulled the stick (not to the max).

What you are suggesting is an interconnection with both SS (Bus bar or by Electric synchronisation) and in abnormal situations you want to disconnect this synch.

A lot of engineering ahead for a feature which will be of -no use- most of the time.

There is a visual indication of resultant SS inputs on PFD on ground.

mm43 post: http://www.pprune.org/tech-log/45283...ml#post6497401

The same could be said for Stall Warning and a lot of other basic items that are required by regulation on a normal airliner.

Lotta' good that does at FL 350.

The yoke in your gut on a normal airliner tells you the other pilot is pulling hard. You don't have to look at a display or at his hand, or a Trim in Motion alert. Does the A330 have a Trim in Motion alert?

mm43 made also a kind of similar proposal … but No please !
Not another PFD item you need to concentrate on and add to the scanning - soon we'll need 5 pairs of eyes to collect all those direct visual targets ...


That’s a good point. The BEA note mentions a few altitudes but the source is not specified and neither if all recorded altitude data were consistent …


Question : Is the FDR settable at the airline request ?

On the media side, above all the news media formates … must be a reason why newspapers are in free distribution at airports.


Do I have ever said anything like it … Please quote !
MWS has well tried to explain but you don’t seem to hear …

Thanks JD-EE, Well said.

If that turns out to just be a media invention, reported in so much mainstream European media, that's pretty shameless, especially included in the timeline as a direct quote.

But this thread and the discussions here of what is actually known (and variations thereof) have all been very rich and useful. Thanks to everyone.

Ok, that's what I wanted to hear..., from someone who actually flies the A332. But while on the subject, have you any personal ideas of how best to ensure that the PNF knows what the PF is doing with the side-stick?

There's another way of looking at this, i.e. as Captain you either have confidence in your F/O and can attend to the necessary if hand flying becomes essential, or you are caught with doing it (the flying) yourself. You may never know which until that time comes.

AoA definition
 

Not for the A330 or any swept-wing transport I know. See for example the Perpignan accident report for a definition of AoA and vane angle, Boeing's Performance Methods, or Airbus' 'Getting to grips'. Must be light aircraft thing.

The zero-lift AoA varies with flap and slat setting, spoilers, and cg. For the A330 in clean configuration it is about -2 degrees. For the airplane, 'trimmed' lift involves the wing, horizontal tail and fuselage contributions to lift and pitching moment.

CONF iture;
Yes, it's possible but complicated.

The JARs, FARs and CARs, (Europe, USA, Canada), require mandatory data frames which record parameters at mandatory rates, (frames-per-second) on the FDR.

The regulatory standards are uniformly, pitifully, low when it comes to recording aircraft data. The schedules for mandatory parameters in the regulations are complicated, having to do with manufacturing and original aircraft certification dates. I'm working right now with aircraft which legally require about 30 parameters and that's exactly what they have and nothing more; later certification dates require up to 88 parameters.

The A332 which was operating flight AF 447 had about 1300 parameters. My bet is most of them are engine parameters, then system parameters, then flight parameters, (instrument, ILS, 'g', aircraft performance) and the fewest, if any, will be ECAM text, FMA text, GPWS and TCAS text parameters.

One of the motivations to have more than the minimum number of parameters beside flight safety is maintenance troubleshooting. Most aircraft systems today are self-reporting but often ACARS-type messages are not sufficient for complex troubleshooting. Engine monitors record enormous numbers of parameters separately from the FDR as do some other aircraft systems. We know this was the case with AF447.

Regarding the recording of parameters, (which really means designing a large data frame into which engineering data is placed, which is later changed into readable parameters by the DFDAU), that is a very complex process and piece of software which costs an enormous amount of money to construct. The work is almost always proprietary so there isn't any sharing of information done in the industry.

The thinking behind leaving out the RHS airspeed would likely be that there were "two" such parameters and so there was no need for "three". Much of this work is the victim of "statistical thinking"...that "averages" can actually tell a rich picture, when in fact they cannot; a clear example is the one we frustratingly have before us.

For many reasons, some historical, the kind of investigative work now being done using the FDR data is not, quite frankly, the primary consideration in building data frames which go beyond the legally required minimum parameters. It is cost-savings, usually through maintenance, not investigative capability, that is the priority, but that is changing.

To illustrate the potential for the number of parameters possible if the data frames were actually programmed and installed, the C-17 has about 40,000 parameters. Military FOQA however, is mission-oriented. Reliable dispatching is the priority though flight safety is part of MFOQA.

The B787 will be a remarkable aircraft in this regard. It will record thousands of "standard" parameters and leave many thousands off the record. Should trouble develop with a system however, the recording system will shift resources and storage to that system and begin recording those parameters which are related to the system providing a far more detailed recording for investigative work.

In a word, the answer to your question about airlines being able to "program" FDRs, is "yes". Anything can be recorded for a price. Designing the data frame and buying the license to use it from the manufacturer, whether a major one like Airbus or Boeing, or corporations like SAGEM and Teledyne who retain standard data frames for most aircraft types or others who have been hired to do the work themselves, is the way such capability is achieved. For changes and new installations for aircraft already in service there is always an STC involved and that can be extremely expensive and a very time consuming process to accomplish. Most airlines are so thinly resourced and working on such thin margins that getting such work done is very difficult.

The reasons that the #2 airspeed parameter and many others, (I suspect no ECAM messages are recorded), are not present requires a more lengthy explanation but essentially the reason involves cost.

A good link for some basic info in "CAP 731" is at http://www.ihst.org/portals/54/Attac...20L_CAP731.pdf . See especially, Appendix B.

None of this discusses the QAR, primarily used for flight safety analysis programs. These recordings are usually far richer, with many more parameters. Such recorders are not crash-protected, (the QAR unit on AF 447 was mounted in the 800VU rack brought aboard the Ile de Sein; hopefully the card survived and they can read it).

I'd be happy to exchange PMs for further, as it's a bit OT.

Normal airliner?
 

GB:


Normal airliner?

-Visuals make no sense on FL350 but does when - normally - needed the most.

-As engineer i'm an outsider but do you really have eye in what the PF is doing with his yoke in such a mayham? Don't you have your own role by then?
Maybe you are right and they had better installed a yoke to become a normal airliner, but that doesn't change the FBW philosophy and in fact B is or will be as much flown by wire than A.

-Trim in motion alert: only visual for as I know....and that will be a proper enhancement: to make it audible too.

a footnote
 

Just a footnote here.

From this France Soir article:
Airbus, la descente infernale : Tout s

where the quote is part of the timeline:

"2 h 11 min 45 s. Tandis que toutes les vitesses redeviennent invalides et que l’alarme de décrochage s’arrête, le commandant de rejoint les deux pilotes dans le cockpit. « Je ne comprends rien », lâche l’un d’entre eux, affirme sur France Info Michel Polaco, pilote instructeur et ancien patron de la station. L’avion tombe alors à grande vitesse et il n’est pas sûr que dans la nuit, en pleine turbulence et au milieu des alarmes, les pilotes s’en rendent compte tout de suite."


It seems that this information is coming from French journalist Michel Polacco (name spelled with two c's), who seems to actually be a well-respected French journalist with French public radio, France Inter, specializing in defense and aeronautics reporting. (Please any French members correct me, because he seems well known.) He is himself licensed as a pilot and instructor and also flies helicopters. He has a blog called Le Ciel par Michel Polacco, (The Sky by Michel Polacco), www.polacco.fr which seems well-informed reporting about current aviation news.

I'm sure we'll know more when the BEA report comes out later this month.

Hi,

A33Zab

Airbus FBW serie was conceived with the aim to make the flight safer and also to streamline the operation of the aircraft
One may wonder if the designers still had this goal when they decided:
Remove the beeper trim wheel movement
Inhibited alarm when the stall speed is below 60 knots

Another media episode in this saga.

How such firm conclusions about pilot training can be reached on the basis of the massaged information that has already been released is beyond me - well actually it isn't beyond me as such, it is simply depressing.

I suspect that there are serious issues with the way the Airbus is to be operated in such a non-normal case.

According to some of our esteemed posters, the notion of stall warners that turn themselves off, overly sensitive controls, lack of multicrew coordination with regard to the flight control command and position, autotrim systems that leave the pilot with full aft trim and the alleged volume of contradictory warnings and cautions are as inexplicable as a design as the apparent actions of the pilots.

Also, does anybody remember this incident? The A330 radar that didn't paint a CB. This has probably been answered somewhere, but which radar configuration was fitted 447?

Hi,

M Polacco is indeed a journalist well know in the aeronautical press
Usually he is seen as conservative and not giving into sensationalism
Some comment that he is even too cautious.
It is therefore surprising that this time it will suddenly gives in the sensational

Apparently ... (from BEA report) the pilots seen something on the radar ... as they warned the cabin crew of some turbulences aera ahead their flight ....

Hello

disclaimer : this thread moved along too quickly for me to be able to cath all ; apologies if what follows was already discussed, I don't think so as a search on the word "abnormal" didn't return any match.

Since the publication of the note by the BEA (btw, it's not a report, semantics matters here), I was wondering why the THS would have stayed @ 13° pitch up, even when the PF made nose down inputs on its side stick.

2 answers were possible :
- it's normal (per specification, not meaning it's sensible in 447 case) ; but why ?
- it's not normal, and indicates a failure / bug in the THS or its command chain .

It now seem to me that "it's normal", i.e. the aircraft managed the THS as its conceptors wanted it to do (= no failure).
Indeed, we have :
- the ALT 2 LAW which is load factor pitch / direct roll / auto-trim / ...
- the ABNORMAL ATTITUDE LAW which is ~ the same as ALT 2 LAW with the exception of the auto-trim being unavailable.

The ABNORMAL ATTITUDE LAW is triggered if (non exclusive list):
- the [mesured I presume] speed is below 60kt
- the AoA is above 30°
Per the BEA note, at each time after the beginning of the final descent, one of these two conditions was met.
So the ABNORMAL ATTITUDE LAW should have triggered, meaning the auto-trim was lost, hence the THS stayed "stuck" at 13° value.

My question for those in the know : Does the ABNORMAL ATTITUDE LAW activation also trigger a message indicating to the crew that the auto-trim is unavailable ?
I know the DIRECT LAW does that ("USE MAN PITCH TRIM" on the PFD), but what about the ABNORMAL ATTITUDE LAW ?

Thanks.

Apparently... a radar paints returns with varying degrees of severity and decisions are based on that. Clearly some returns were apparent, but that doesn't mean the convection was accurately painted or that the whole area was adequately painted.

Hi,

Not an aswer to your question but in the BEA note:

Around fifteen seconds later "at + - 2 h 12 min 17" , the PF made pitch-down inputs.
For how many time ?
And
the speeds became valid again
the angle of attack decreased (but still over 35°)
So .. abnormal law or not ?
simultaneous inputs by both pilots on the sidesticks
Up or down inputs ?
As already commented before this BEA note don't give real clues about what are the pilots actions and what they tell ... it's just a riddle
Not big difference between this note or any press article in a newspaper like "Le Figaro"

gums:
Doesn't that add another feedback/scan loop to any attitude change on instruments? Instead of setting a pitch attitude, you make a 'g' input and correct to desired attitude? Maybe I am overthinking this, and in practice it boils down to the same thing - set pitch by looking at the attitude indicator, then trim it in (Viper Coolie Hat) or AB auto trim?

THS versus elevator versus stabilator
 

Your thinking, Wolf!!! We might all be "thinking" too much, but down deep I feel we're homing in on a quirk with the Airbus design.

To clarify my understanding, it seems the 'bus trims for one gee ( Nz) in "normal" modes. It is roll- compensated ( unlike our Viper), so the pilot need not back trim while in a turn. Makes it easier to maintain a level turn, but how about a descending turn or a climbing turn? It is also compensated for pitch (unlike our Viper).

So my feeling is the thing trimmed the THS for a nose up attitude, and things got worse with low or no speed inputs to the "confusers". Worse, the AoA protection seems to have gone on vacation, so we have this beast with almost full nose up pitch trim and no AoA input helping to get the nose down. Something ain't adding up.

Our jet had no elevator - the whole stabilator moved, both of them. They also moved differentially to help roll. Nevertheless, our jet trimmed somewhat like the Airbus to maintain a gee command. Gear down it blended AoA and pitch rate into the gee command to make it "feel" like a normal jet. We still had a little trouble trimming for an AoA or speed like "normal" jets, but what the hell.

Only time we had "autotrim" was with otto on in "altitude hold". So if we pulled back the throttle the thing would trim nose up as we slowed until reaching 13 or 14 degrees AoA, then we would slowly descend( had one CFIT doing this, BTW).

Bottomline: The jet didn't help the pilots. The pilots were nor sure of the exact control authority and "protections" that they had. There will be a sad finding in the end, I fear. And i pray that training and maybe some slight mods to displays and control laws will be implemented.

gums, thanks (sorry about the CFIT, losing a brother pilot always hurts) for the amplification. From what the BEA has released, it appears that the THS commands to nose up were from the side stick commands ... but if that was in response to a low speed stability input, a previous trimmed condition, or anything else (or a combination) remains unclear to me. Will hope for clarity in due course.

I am still not sure how well the BEA analysis can suss out from the data available just how turbulent (or smooth) the airmass was just before, during, and just after the initial upset. Perhaps their next release will have some more clarification on that, as flying in turbulent air not infrequently adds to the number of control inputs (particularly if the auto trim in one channel or another is not in play). Working near cells that big, you are bound to have some vertical movement of the airmass, or run across some. The question is, at what magnitude?

This discussion merits a momentary distraction.

First the idea of driving the PNF stick in response to the PF inputs. The first issue I have is that the side-sticks are 'handed' - the left stick leans toward the cockpit center by perhaps 5-10 degrees, the right stick leans the opposite direction, presumably to 'sit' nicely in the appropriate hand. Does that have any implication as far as the PNF interpreting the stick inputs, as opposed to giving those stick inputs. I suspect it does? Secondly, my impression is that stick inputs are generally subtle (since the stick itself does not have much travel - not sure of distances). So the second concern is whether these stick inputs would be particularly noticeable, particularly when things are going to hell in a hand-basket? I believe gums noted in prior post that the PNF is much more likely to notice the change in 'g' due to control inputs (my butt is being pushed into the seat = we're pitching up...). Given that the sticks were motorized and driven, what happens when a dual-input occurs? Currently the system issues an audible warning "dual input" and I believe sums the inputs. Override can be achieved by pressing the "take control" button. With a driven system what happens?

The throw away comment above regarding stall warning is spurious and flippant in my book, you could equally say the same thing about a fire warning, etc. Nothing to do with what was being discussed.

My question is how, given the "confusers" - as you delightfully put them - were not in control of the aircraft after the loss of speed indication was detected, was the "thing" supposed to command a THS pitch-up? The autoflight system will have maintained a slight pitch up prior to disconnection, but nowhere near the angle the aircraft ended up at.

@ jcjeant
"So .. abnormal law or not ?"
Conditions are met for the abnormal attitude law. So, I guess yes, until proven wrong.

@ DozyWannabe
IMO, the pitch up THS came from the pitch up pilot inputs.
Basically: autotrim.
Pictorial: "My pilot wants nose up", thought the plane, "let's help him with the trim, so he doesn't have to hold the sidestick anymore".

AZR, that's certainly a possibility, but I don't want to say one way or the other until we know for sure. It's all too easy in this kind of forum atmosphere to equate the theory that the THS movement was pilot-induced with "blaming the pilot". I know they're not the same thing, you know they're not the same thing, but there are some who will get indignant about it.

Uncommanded nose up trim by pilots
 

Well, Doze, this is the big question.

How did the THS get trimmed to near the limit?

What happened to AoA protection? And that looks to be a biggie according to the manuals' description of the "protections'.

How did the crew not see attitude steadily increasing? I thought attitude sensors and displays were independent of the pitot-static system? Same for AoA protection.

I can tell you exactly how my little jet trimmed the stab to full nose DOWN as it entered a stable, fairly smooth deep stall. We ran outta nose down pitch moment. Already posted the link and enclosed snippets from the test pilots. So we were briefed, watched movies, had a new switch installed to help us, etc. Better yet, our designers and military management were not so damned proud of their design that they refused to change a few things. They didn't continue claims that "the system did exactly what it was suppose to do" ( even tho it did EXACTLY what it was supposed to do, it wasn't designed for the condition we clever pilots could get to).

But now we see a similar phenomena in the Airbus, and due to a combination stabilizer and elevator, it is possible that the elevator doesn't have the control authority to get the nose down at full forward stick due to the disconnected/locked THS.

Autotrim
 

It would seem logical to have a slight time delay in activating autotrim.

When you make a demand on the elevator, that needs to be in the context of the aircraft's current trim.

If the aircraft were to quickly trim while you were making a pitch input, the aircraft wouldn't be in the same trim when you relaxed the input.

The idea must be, lets wait and see how serious the pilot is about this control demand. If he keeps it up for say 5 seconds, he must be serious, so we can trim some of the back stick out.

But in the case when the nose down control input returned airspeeds to functional in the deep stall. The stall warning return probably discouraged the nose down input inside of the delay time. Therefore the THS did not move toward nose down.

The actual aircraft control logic is no doubt proprietary to Airbus. We will only get applicable snippets of it in the control analysis when BEA finally publishes. There are probably clues in other AB accident reports how the thing works.

Gums: The initial 'zoom'climb' (for want of a better description), occurred prior to significant THS movement, presumably as a result of normal crew input. Only after "the PF maintained nose-up inputs", following TO/GA selection did the THS move significantly away from what might be considered a normal attitude of 3 degrees.

I believe AoA protection is diminished as follows in ALT LAW:

My reading of the BEA note is that the THS did exactly what was commanded by the PF. The aircraft was already in trouble quite a while prior to the THS reaching 13 degrees.

THS trim not immediately commanded
 

Right on the spot, Doze!

I realize that the THS didn't start moving until later in the sequence of events.

Your AoA protection quote bugs most of we pilots here, as AoA is the primary concern with a stall or approach to a stall, not airspeed. I look at the wimpy AoA bars on the display and it's hard to understand how an important indication is not "expanded" vertically when it becomes an active player in aircraft control.

I also note confusing inputs to the "confusers" re: speed versus AoA when either or both becomes primary for "protecting" the pilots and the jet. You would think that the jet would revert to AoA if speed was deemed unreliable and SCREW THE SPEED! And then quit giving warnings until the speed was not only deemed reliable, but well above the computed stall speed ( but AoA still determines stall, not speed).

BTW, we didn't call our stuff "protection" as much as we called them "limiters". About the only "protection" control law we had was added during FSD, and it was a yaw command by the system if AoA was above the limiter value. It was one of the things that made our deep stall stable and kept us from entering a spin. It didn't work inverted, so it was possible to enter an inverted spin when in an inverted deep stall, kinda scary, huh? Oh well, a small thing we had to put up with, heh heh.

For whatever the cause of a/p loss, the need for PF to 'correct' ('climb', 'roll'), and THS behaviour, the time of accident begins at 15 seconds prior to, and perhaps 15 seconds post, a/p loss. Upset prior to loss of a/p? Quite likely, for whatever the reason it dropped out, the definition for upset was concurrent. If in a climb that cannot be corrected, that is LOC. Whether electro or Weather, the definition for mechanical failure also is met, for loss of authority qualifies as loss of mechanical controls. Airframe damage is also quite possibly in there, the g string will be interesting.

You still hoping the tail came off, bear? Yeesh!

@gums - GarageYears was the one talking about angle of attack - I'm a logic man, trig and physics aren't my strong points!

Control laws and mechanical failures
 

@ Doze: Sorry to cross-reference posts. I apologize.

@ the Bear: It's possible that parts came off the jet or that some systems had mechanical failures ( not computer failures), but I doubt it. The CVR snippets we have so far are not filled with "whoa!", "Holy crapola!", or other indications that the ride was very rough.

The gee and other aero data from the recorders will provide some clues as far as parts falling off or actuators jammed or.......

@ all here:

I only use my own experience and understanding of another FBW system, with it's "laws" and logic, so folks won't think all FBW systems are the same. Additionally, I hoped to let folks know that despite some claims/assertions that the stick moves the control surfaces the same way, the same rate, the same amount, etc. all the time, even in alternate laws - THEY DO NOT! We're not in Kansas any more, Toto.

I also wanted to show folks that there are flight conditions that the designers never figured on when developing the system logic and gains and "forward-lagged rate" inputs to the commanded gee or roll rates. Same for the reverse. For example, the roll rate command we had used a lot less onset rate when rolling into a bank than rolling out. Next time you see a T-bird performance, note that the jet stops the roll on a dime. Contrast this with the Blues, with their pseudo-FBW system. I can see the slight hesitation when a Blue stops his roll ( the solo guys/gals). The Viper looks like a video game and the roll stops instantly.

From reading the many posts on this and previous threads, as well as some of the linked material, it appears to me that the Airbus design philosophy is biased against what might be called "tactile feedback" to the pilots. This bias appears, in turn, to stem from a philosophy that, in regular operations, it is best that the pilots to tell the computers what they want the airplane to do, rather than command the controls more or less directly to achieve aircraft performance.

In a sense, AB aircraft have two autopilots; the traditional one that would, in a conventional aircraft, command the controls to do what the pilots command via knobs and switches, and the flight control system, where the pilots move what appear to be more-or-less conventional controls (stick, pedals and throttle) that actually only command the computer to move the controls with considerable computer intermediation to achieve, for instance, a stable bank angle or a max climb angle without stalling the aircraft.

I can see how the idea that the pilots never actually command the controls would lead to AB believing that tactile feedback through the controls (or control position, as in moving throttles) is not necessary. But that philosophy is flawed on the rare occasions when the pilots actually are commanding the controls directly, as was the case for 447 in roll in ALT2 law. The PF had no feedback from the stick other than a/c performance, the PNF had no physical feedback from his controls re what the PF was doing, and (according to an earlier poster who had flown the 330 in ALT2 law) the aircraft performed quite differently in response to stick inputs than did the simulator, which of course is almost certainly the only time the PF experienced ALT2 law prior to the incident.

So, in essence, the PF was flying that particular configuration for the very first time that night, in the soup with contradictory speed indications, and without the other crew being able to fully follow just what he was doing.

This was compounded by AB using the same interface, with the same lack of tactile feedback, for two very different tasks: telling the computers to place the a/c in a certain attitude and hold it there in Normal Law vs directly commanding the ailerons in ALT2 law, which runs the serious risk of the PF not making the appropriate modifications to his inputs until after a short period of actual experience with the differences.

Could it be an erroneusly low airspeed in all ADRs such that the airplane was actually deep in the overspeed and then the APs disconnected and the pilot carried out unreliable speed procedure memory item when above 10,000 ft: pitch 5º, climb thrust.

What was the pitch and AoA at the time of the AP disconnection? I think that is a critical information. is it available?

if these were low, that scenario would explain the pitch up input, and such a sudden and large pitch change (say almost 5º) at that level and speed (overspeed) would make possible a very large lift increment and climb rate. but I am not sure that a stall could result from this.

we will have to wait.

Forgive me for asking the following question which I have not seen answered anywhere else but, if it has, mea culpa.

From the information provided by BEA so far, it seems that the aircraft in question descended at a great rate of speed. Would not this "great rate of speed" descent be felt by anyone? Wouldn't PF and PNF, as well as the captain, not actually feel this descent.

I know as a passenger when an "air pocket" is encountered and the aircraft loses
a bit of altitude that is certainly felt. So I can only imagine the descent experienced by
AF44 would be felt quite a bit more. No?

A constant descent rate = no vertical acceleration = 1 g. However the out-of-vertical part would be sensible if the attitude of the plane was more than 15 degrees nose up. The plane would appear tilted upward to passengers with good sense of balance.

Tex Johnston's famous roll of the 707 family prototype was done at 1 g relative to the fuselage. A glass of water could be set on the dash and would not empty during such a roll, if well exectued.

rgbrock1

From the information provided by BEA so far, it seems that the aircraft in question descended at a great rate of speed. Would not this "great rate of speed" descent be felt by anyone? Wouldn't PF and PNF, as well as the captain, not actually feel this descent.

I know as a passenger when an "air pocket" is encountered and the aircraft loses
a bit of altitude that is certainly felt. So I can only imagine the descent experienced by
AF44 would be felt quite a bit more. No? [/quote]

Take your bike, coast it off a cliff with your eyes closed. Tell us if you felt anything before you hit the ground.

Forgive me if you've already done this :}