Protections not working in Alt2 + ADRs fault
 

Hi Franz,
Yes, it will be limited to the duration of threshold excess, when load factor will be lower than 0.5gs, IF, at any time, they applied that much ND, which doesn't seem to be the case either.

Yes they are lost. This protection, like any other active protection, was lost from the start of the event when EFCS is directly set in Alt 2.
UAS is very nasty, only g-load protection (which is passive) will remain and protect the airframe from g-load exceedances.

No, same as above, it doesn't work with UAS in Alt 2. There was no more "Stall_Speed" to refer to for the system to make it working.
"Bank angle compensation", should mean that the system will try to bring back the wings level or prevent any increase of bank angle while reducing NU attitude.

It's not easy to grasp it at the first reading.
When going to Alternate law mode, the five active Normal law protections are lost. But, depending on the kind of fault causing Alternate law switch, two protections may be replaced by Alternate ones (Low Speed and High Speed).
In our AF447 case, with a triple ADR fault, those protections are lost as well, and it seems very bad as they could have prevented this crash.

Hi CONFiture,
You are right, but ISIS includes more functions than default standby. About ISIS access, flying the aircraft from the RHS would make it harder for the PF to check ISIS, which is closer, in the central console, from Captain's seat.

AoA wasn't an issue when speed issues started. I was talking about the first PF reaction inducing the initial climb that could be related to his focus on roll and initial sharp altitude drop. I agree that it doesn't explain why he continued NU orders when, 40-50 seconds later, the aircraft stalled. But disorientation and instrument disbelief could cause the later orders.

It is quite hard to understand.
But, we never faced the same stress and situation as, with hindsight, we are fully aware of many things they may have never acknowledged during this event. Captain's return could have bring some confusion with him. Did they agreed about the situation? Was the PNF nose-down in ECAMs reading while the PF pursued stubornly his false impression of what really happened?

I still believe that a BEA hastily release of raw data would have caused more harm than good. Many things really need to be checked and cross-checked before reporting them to the public. Without expert analysis, it may be very harmful to everybody. Any inquiry needs time, patience and in depth processing in order to avoid mistakes and wrong conclusions.

I would like to know everything, straight away, but not before everything is well sorted out and seriously verified. I'm pretty sure that there will be no final report this summer, as some believe, only an interim one.
We'll see.

From takata

FWIW after following this and other thread for many months and wanting to believe the PF reacted to indications (not terrified rabbit pulling up), takata's theory is what I believe happened. That in my view is saying a lot after all the posts and credits takata with a conclusion that has taken so many months of analysing, questioning and thinking.

My worry now is the PF (RHS) instrument datas were not recorded and the BEA may have difficulty concluding about why the PF inputs were as recorded. But I fundamentally believe the PF was reacting to what he saw on instruments (outside was "black", no horizon). I do however think he failed to integrate his feelings from the seat, i.e. G forces over time (which probably began before AP disconnect with subtle descent). I can excuse him from that in the urgency of the situation, but am still trying to understand ~30 sec of 7000fpm climb.

My hope is that the A330 will become even safer (it probably already is due to modified UAS procedures promulgated). Surely we must find a more resiliant way to measure airspeed than those pitot's. But if takata is right, we must find a better way to reliably measure altitude at all times as well.

can you explain the different places of the pitots between A+B, can this have an influence of the reliability (ice)

I have little (approximately nil) knowledge of AB pitot statics and only those Boeings which I have flown. Generically, I suspect that you will find both marques are similar with multiple pitots around cockpit FS and statics a little further aft (to stay in a shallow boundary layer region without too much local flow acceleration).

Ice problems are probably a bit too specialised for my general comments to be of much use.

Thales have (had) issues. All a/c operations have 'issues'. Transport does not function in a vacuum. A/C are certifiably up to the challenge, but they do not fly in a laboratory, with scrupilously maintained parameters.

To be safe, maintenance must be relentless. Pitot probes gobble up whatever atmosphere they are in, they have no choice. Salt air, grit, moisture, pollution, it is the fact of life. Thales had drain corrosion problems (from memory, original thread, and subject to flame). So in a bad way, the probes developed a less than reliably redundant read? Maybe.

From takata and his point re: three way adr rejection due discrepant reads, a slight hesitancy may be allowed re: ICE.

IMO, ICE would present as other than an instantaneous three way discrepancy. It seems more reasonable to entertain airflow changes. imo.

I have read only LandIT's repost of takata's post. It is a feast, and his best yet, imho. Injecting TCAS ACARS for altitude suggests perhaps looking at W/S for airflow disturbances?

I am relieved and fully support any writing that gives an objective basis for speculation. Of course the crew were qualified; where in the world did the initial objectivity of this forum go?

LandIT. I spot an idea in your post. "He did not incorporate his feelings from his seat".

Should He? That way lies danger. He was in the panel, making the best sense of what he saw, I would guarantee it. It was in flying by the book that did them in....... Interpreting "G", especially over time, isn't that potentially a conflict with the a/c?

I think takata is spot on. PF was likely F/O, from the RHS. Not relief pilot?

Chris

DozyWannabe, #466

I don't quite see the connection there. It's almost as though you are
implying that you shouldn't fly in any new a/c until it's at least 5
years old, to get all the bugs shaken out, which seems like a spurious
argument.

While you may need to wait a few years before upgrading to any new
version of windows, (I'm still using W2k on one development machine, but
for other reasons), a/c are not quite the same thing. Of course,
statistics can show anything you like, but the answer to that is to take
samples from > 1 data source, especially where a given data source is
suspected to be biased or unreliable.

I doubt if there is meaningfull difference in the figures anyway, as accident
rates, in terms of flight hours are down in the noise...

for John T:

If ice is the trigger for a fault in the function of static ports, what sort of evidence does that leave behind? Your posts leave me an uneasy feeling that a possible fault that left no evidence was involved for a part of the upset event.

If that is the case, it has remained hidden. Sufficient function was retained or regained to leave coherent altitude data for most of the event.

hi Lonewolf.

Give me a steer, here. My take on the accident involves mostly the idea that the initial event happened rather quickly, and was unrecoverable almost as fast.

Aren't 'Upset' and "Loss of Control" two separate regimes? My understanding is that Upset need define one set of criteria, and LOC another.

Upset I think, includes control excursions that are quite recoverable, similar and quite consistent with loss of a/p. Not boring, but not life threatening either. A Loss of Control exists when command of the a/c is lost?

So, for whatever reason, what caused 3ADR reject and ALTERNATE LAW2 satisfies 'Upset'? The zoom climb, at least for now, defines LOC?

Early in #4 thread, I think, the criteria for Jet upset (regardless of airframe type) were posted here. Not so for LOC, but LOC is pretty simply "Loss of Command" (mechanical or Pilot induced?)

Whatever barometric anomalies you introduce into the theories, you still have to explain why two competent pilots allowed or caused the pitch attitude to change so dramatically without an apparent word said between them? Here's hoping BEA tell us something useful at the end of the month. Otherwise I'm afraid it just does not 'compute'.

Never having been there before, neither aircraft nor Pilot 'knew' what they were "doing".

At least Orville and Wilbur expected the unexpected.

Lets all keep in mind when discussing pilot action....we have had 2 YEARS to review, analyse, review, discuss...analyse...... they had minutes....NOT a situation any one of us would ever want to be in...

Eagerly awaiting the next installment from BEA...

"Quickly" is a relative term. Depending upon how responsive your aircraft is, quick time horizon will very.

At some point in a three thousand foot climb, which took about half of a minute, remedy to the pitch problem seems to have not worked, whatever was tried.

For me, thirty seconds is a long time if what I am dealing with is simple attitude flying, but as I have stated time and again, I am at a loss concerning what the PF was seeing (and for that matter, what he wasn't seeing) from the event's onset to its conclusion.
I would use "upset" to describe those unusual attitudes and conditions that precede stall, or other out of control flight, and classify only stall and beyond states as "loss of control."
Caveat: if you have a control channel that doesn't work, you may be, by default, in a loss of control state. If you have spoilers or slats going wild (there was a bold face for that in the A-4 NATOPS that I can vaguely recall) you may be in OCF until you get the asymmetry fixed.
You can call a trim runaway a loss of control, unless you are able to overcome it and regain control. Had that happen in a helicopter once, it was an adrenalin rush, but it was recoverable.

Bear, I am not sure I'd phrase the distinction as you did.

Over the past two years, a number of pilots who have flown big transports into stalls (usually on purpose with that one degree per second entry method) have told us how the stall recovery went. What seems to be true, (other than the deep stall problem of the T tail aircraft) is that recovery is often viable when partial control over some or all flight surfaces is exercised in a particular way, likewise power adjustments, to affect a change in airflow and restore lift, and thence control.

(Aside: If you want an interesting loss of control story, take a read on the Vortex Ring State flight test done by two test pilots for the V-22 Osprey as they investigated one of the V-22 mishaps that involved VRS).

I don't see it that way. I don't think zoom climb is LOC, it looks to me more of an upset. Once stalled, you could argue LOC. I'll let those who are more current in state of the art terms correct me on that, as necessary.
A stall due to windshear is neither mechincally induced, nor pilot induced, so maybe a third category is needed. Or a fourth. ;)

takata;
Having done for some time now the work of interpreting flight data in flight data analysis programs I fully concur with your views.

The release of "raw" data is simply never done.

I made the observation long before anything was released after the recorders were found, that the data would not, (and may not) be able to provide us with the full picture of what happened and why.

There is no "magic" in the flight data or the CVR. It is without question, an interpretive process requiring thorough training and long experience. How someone may imagine themselves as capable of doing better alone, is a puzzle.

The release of the traces, (which is a very long way from "raw data"), is sometimes done as part of the report, supporting the text and investigative work. Asking for or even demanding "the raw data" is the clearest indication of how little someone understands the flight data and accident investigation processes.

The impression that "the raw data" will give final, conclusive answers and "we will finally know what happened", is a misconception of the flight data and investigative process. A release of "the traces" without a thorough interpretation would indeed be a serious mistake and could even delay an understanding of what really happened.

While there are a few here whose capabilities have clearly been demonstrated and whose interpretations would benefit from being able to work with "the traces", the investigative process does not work that way and those capable of the work would know and understand that. The vast majority of us are not the "check-and-balance on the BEA" some may imagine themselves to be. When the report and the data are both available, there will be time enough for those who can do the engineering and flight safety work to verify, and critique where warranted.

Thanks, PJ2.
Count me in your camp....

believe it or don't, me too.

When the Reaper enters the room, many present begin to whistle. Human beings function (and desire to) in states that can be managed, and understood. If understanding is not available, we trust others to supply some manner of acceptance by proxy. Lacking any understanding or management, we choose denial.

This is true, and even perhaps more so, for those who believe knowledge is perfection, and there is an answer for everything. There is not, and fear is therefore inescapable, and natural.

It is possible that this Airbus and these Pilots performed perfectly, and the consequence was unavoidable. Life has risks, and to the extent that we honor that, it is incredibly exciting.

I think this thread is back to still water. The BEA report will never satisfy everybody. It satisfies me, and I haven't even seen it yet.

How do you know that?
All we have at the moment is an interim 'cherry-picked' extract from the initial data from the recorders (FDR and CVR) , as described in text format by the BEA, and then translated into another language (English), with all the usual pitfalls of those processes....

Yes, we're all frustrated by the limited amount of 'hard' data we have.

Yet, the BEA report seems to have satisfied the 'meedia', which now have switched to 'DSK', 'Murdoch', the 'Red-haired Witch of Wapping' and other more juicy bits.

If I was working for the BEA (and no, I'm not) I'd heave a sigh of relief. To do serious hard reliable work, it does help not having the media, etc., breathing down your neck. Even if getting a full interim report out by the end of July might have seriously :mad: up my holiday.

Hi,

Are you sure ?
Seem's not all meedia

France/Monde | L’AF447 ou le droit de savoir

Thanks for that, I had a momentary visual of The Sun running coverage, page 3 perhaps, of Red Haired Witch's juicy bits, and nearly poked my eyes out with a pencil. (Yes, I still know how to use one! )

The media pressure has got to be a process obstacle for BEA.

Been in a few (thankfully) scenarios in my life where the Media took and interest ... it's not much fun.

Not at all - it's just statistically more likely that there will be a marginally higher risk of an incident or accident in the first years of a new airframe's life. The chances of being in an accident when boarding a new type are still incredibly unlikely.

But the facts bear this out - the 727 had a series of very nasty accidents in the first few years of service due to a combination of pilots getting to grips with the tail-heavy aspect of the design in combination with the powerful flaps causing a much higher bleeding-off of airspeed on approach than they had hitherto been used to. Both the Comet and the DC-10 revealed serious design flaws in their first few years of service (and the L-1011 revealed a minor one, regarding the weight -on-column required to disengage the automatics). The 737 proved that it wasn't as longitudinally stable as the 727 (unlike the 727 you couldn't rescue a fast approach by throwing the gear out early) and the A320 had some mode-confusion issues in her early days (of which Habsheim was *not* an example).

Those are just some examples, but I think it's a pretty good rule of thumb. It's a testament to the improving quality of aeronautical engineering over the years that the number of these incidents has gone down dramatically (the 757's record was unblemished until the mid-'90s and the 777 has suffered only a single hull-loss, as has the A340 in service).

Believe me - that's not the comparison I'm making! For a start, home and business OS "teething problems" usually *are* down to flaws in the design and implementation rather than the users getting used to how they operate. This isn't relevant to an aviation discussion though. :)

Funnily enough, it was A33Zab who brought up the safety record, not me...

I'm sure the "Red Haired Witch of Wapping" is not featuring in the BEA's analysis of the demise of AF447, and likewise the same lady wouldn't have found anything of salacious media interest worth publishing in her former rag(s).

On the other hand, Le Dauphine's latest article - L’AF447 ou le droit de savoir (AF447 - The right to Know) - is clearly pointing the finger at "crew competence" or lack of it, and to the dubious credibility of Air France.
Protect the integrity of Airbus Industries and make Air France and its employees the "sacrificial lamb" is my read on this Irène Perrin article.

Numerous issues are raised, including simulator training and management, but nowhere in the article does the word "securitie" in the safety sense get a mention.

jcjeant - Thanks for the link.

I would like to add to the discussion on "Why the pitch up?" by quoting from and otherwise referencing from two sources - HtBJ by Davies, (1rst & 3rd ed, discussion on the "super-stall"), and from one of the papers to which I provided links a while back on this thread, entitled, "The Effect of High Altitude and Center of Gravity on the Handling Characteristics of Swept-wing Commercial Airplanes" published in the "Flight Operations" [FO] section in the April, 1998 issue of Boeing's AERO magazine.

The goal here is "continuing education" if you will, because the serious discussion on stalling heavy transport aircraft has become necessary as have some points regarding high altitude, high Mach number flight. There are some worthwhile papers which discuss this in great detail but are really tough sledding and the mathematics will be beyond most! I can't lead the discussion as HN39, gums and others might but I do wish to rejuvenate the discussion on the two items which continue to interest us all: Why the initial pitch up?, and the behaviour of a heavy transport aircraft in approach to, and in, the stall. Specifically, I am wondering if the low-damping forces of high altitude flight had anything to do with the eventual loss of control. - PJ2

First, from the Boeing document:

"Maneuvering Stability
"Maneuvering stability, like static stability, is influenced by CG location. However, when the CG is aft and near the neutral point, then altitude also has a significant effect. Since air density has a notable impact on the damping moment of the horizontal tail, higher pitch rates will result for the same elevator deflections as altitude increases. From the flight crew's perspective, as altitude increases, a pull force will result in a larger change in pitch angle, which translates into an increasing angle of attack and g. While a well-designed flight control system, either mechanical or electronic, will reduce the variation of stick force with CG and altitude, it is very difficult to completely eliminate the variation due to design limitations.

"For example, for the same control surface movement at constant airspeed, an airplane at 35,000 ft (10,670 m) experiences a higher pitch rate than an airplane at 5,000 ft (1,524 m) because there is less aerodynamic damping. The pitch rate is higher, but the resulting change in flight path is not. Therefore, the change in angle of attack is greater, creating more lift and more g. If the control system is designed to provide a fixed ratio of control column force to elevator deflection, it will take less column force to generate the same g as altitude increases.

"This principle is the essence of high-altitude handling characteristics for RSS airplanes. Unless an RSS airplane has an augmentation system to compensate its maneuvering stability, lighter column forces are required for maneuvering at altitude. Longitudinal maneuvering requires a pitch rate, and the atmosphere provides pitch rate damping. As air density decreases, the pitch rate damping decreases, resulting in decreased maneuvering stability (see figure 2 and "Maneuvering Stability" below).

"An additional effect is that for a given attitude change, the change in rate of climb is proportional to the true airspeed. Thus, for an attitude change for 500 ft per minute (fpm) at 290 knots indicated air speed (kias) at sea level, the same change in attitude at 290 kias (490 knots true air speed) at 35,000 ft would be almost 900 fpm. This characteristic is essentially true for small attitude changes, such as the kind used to hold altitude. It is also why smooth and small control inputs are required at high altitude, particularly when disconnecting the autopilot.

Summary
"The use of wing sweep and stability augmentation on modern commercial airplanes makes them more fuel efficient. However, flight crews must understand the effects of CG and altitude on performance and handling qualities. For example, operating at an aft CG improves cruise performance, but moving the CG aft reduces static longitudinal and maneuvering stability. Many modern commercial airplanes employ some form of stability augmentation to compensate for relaxed stability.

"However, as long as the CG is in the allowable range, the handling qualities will be adequate with or without augmentation. An understanding of static and maneuvering longitudinal stability is an essential element of flight crew training." (my bold/underlining).

. . . .

"Static Longitudinal Stability and Speed Stability
"STATIC LONGITUDINAL STABILITY
"The term "static longitudinal stability" is the name of the stability coefficient (Cm-alpha) for the pitching moment due to a change in angle of attack. In a stable, conventional airplane, the CG is forward of the neutral point of the airplane (wing plus tail). An increase in angle of attack from trim increases the amount of lift generated by the wing and results in an increasing pitch-down moment. This drives the airplane back toward its original angle of attack. If the CG is aft of the neutral point, increasing the angle of attack causes the airplane to pitch up, away from its original trimmed condition."



Next, from Davies; (NOTE 1: We have seen some of these illustrations from Davies before, posted by others during discussions on AoA, the stall and so on. I am providing pages 121 through 128. By referencing the so-called "deep stall", I am not implying that we have such here in AF 447 - I don't have the background to determine that. What I wish to provide is Davies' discussion on the broader elements of the deep stall, a discussion which I think is relevant to the behaviour of a heavy transport, regardless of kind of AFS installed. NOTE 2: "Cm" is referenced in the last paragraph of the Boeing document, above.

*Handling the Big Jets, D.P.Davies. 3rd ed. 1971. Civil Aviation Authority, London (OP)

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Hi,
The word is not there, but the idea is: the "audit" about security has NOT been published (contrary to promises, imho). There were some comments (in French, and I am not sufficiently fluent in English to translate them):
- SÉCURITÉ - Ce rapport qui pointe les failles d'Air France - Le Point
- L'audit sur la scurit des vols d'Air France serait "trs critique" - LExpansion.com

PJ2,
Thanks.
Can't find my own copy of Davies's HtBJ to cross-check. Is he discussing T-tails in that section you posted?

jcjeant, mm43,
The 'La Dépèche' article seems to have been written by somebody who's either followed the PPRuNe threads on the subject..... or similar ones on French forums.
Nothing new there, and just the same speculations we've seen before.
I wouldn't pay too much attention to it.

PJ2
 

Excellent post and reference , PJ2.

It´s basically what i learned in the aerodynamics-course in UPT 35 years ago, also in view of flying fighter jets. I didn´t learn anything in my ATPL course concerning this matter, but maybe i was not attentive enough.

I had some argument via PM with some posters here about how much the nose would have to be lowered to break the stall at an AOA of 60° and posted some concern to the effectiveness of the THS. This reference states that it is not enough to lower the nose somewhat, and that it would lead to high sink rates and a difficult pullout if altitude would be sufficient. Posters calculated altitude loss to some 5.000 feet. Please, go back and read this reference from PJ2 and reconsider your calculation.

I get the impression that this new generation of engineers and pilots are forgetting, that computers dont change aerodynamic fundamentals, they only can help in manage the equipment being used in a different way. But its still used in the same old environment from years ago, when your nice reference was written down, and even before, when the fathers of flying conquered the skies.

Aerodynamics is unchanged, any aircraft can stall, can be stalled, and any aircraft can end in an unrecoverable mode of stall or spin. Know before, when it could happen and under what conditions it can happen, and dont get near such an situation. If you fail and find yourself approaching a stall, try to get out of it as fast and efficient as possible. There might be only this one chance.

Why would you say that? Airbus acknowledged the pitot issue and released a service bulletin to the airlines months before the accident and simultaneously issued "workaround" instructions to pilots at the same time, while the issue was being fixed. What more could they reasonably have done?

I really don't get this "BEA protecting/covering up for Airbus/AF" meme that seems to have seeped in around the edges. The fact is (as I've said before) that not only has the BEA become a very different organisation than it was in the late '80s, but also that Airbus has been very quick to put its hand up to mistakes and fix them. Neither major manufacturer acquitted themselves particuarly well in the '80s and '90s - it took definitive proof that the 737 rudder hardovers had a technical cause before Boeing stopped pushing the angle that UA535 and USAir427 could have been pilot error, and it took the loss of Nick Warner to make Airbus look long and hard at their interface design. Both companies have since behaved considerably better in that regard.

We could be on the verge of a serious self-examination on the part of the airline industry as regards training, particularly with regard to making sure that pilots be properly-versed in the aspects of the aircraft they are expected to fly - which I gather from many posts on here people think is something long overdue, and yet it would appear that some people still think that finding the design of the aircraft (over and above the pitot issue) at fault in the face of the evidence would be a better outcome?

@CJ - yes, I'm pretty sure that sectoin of the book refers to deep stall in T-tail designs, but the thrust of the description is still very useful.

Hello, CJ;

Yes, that's the section he's discussing: - T-tails and the "super-stall" and the section I have quoted comes right after that specific discussion, (pgs 115 - 120).

I understood his discussion on "the complete picture" at the beginning of page 121 to be relevant to all heavy transport types and not specific to the T-tail configuration, which is why I considered it pointing to what constitutes a "good education for pilots new to high altitude, high Mach number flight", if nothing else.

I'm no longer confident:
a) that this knowledge is taught either on the way to the ATPL or to new-hire pilots on the assumption that they already know it all and,
b) that the "assumption" is correct.

Edit: Thanks Retired F4 - confirms my sense of what's being taught and what is being assumed.

I get the strong sense that Davies' approach to matters of aviation and in particular heavy transport flight, is unfamiliar today, not because today's pilots are less keen and less interested in their profession but because bean-counting airline executives believe that "all today's airplanes are automatic" and so teaching things aeronautical as opposed to teaching the minimum "NTK", (need-to-know) to operate the airplane and pass the FAA/TC/JAR (haven't included Australia here, yet), rides has contributed to the present state of affairs and pilots, as a group, have let management get away with this brand of thinking and haven't taken the bull by the horns because many don't know what they don't know about flying airplanes. Just because one can manipulate the controls and land the thing doesn't mean one "knows stuff". The First Officer of the Colgan Q400 is sadly, tragically, one example. The poor soul was never taught about the business she was in or bread-and-butter aerodynamics, just the NTK about how to work the airplane.

Hi,

To remind that the loss of BA 777 (in England) was (as far know) due to a technical problem .. and the loss of AF A340 (in Canada) was (as far know) a pilot error.

Hi,

Can we qualify the famous "audit report" as speculations ?SÉCURITÉ - Ce rapport qui pointe les failles d'Air France - Le Point

As far we know .. BEA not issued a grounding of all the A330 after all those days of investigations
We can conclude that at today the A330 is not technically implicated in any ways in the loss of the AF447
So with this knowledge .. we can conclude that the BEA final report will show that the actions of the pilots where not adequate for the situation the plane was.
It's maybe not name the responsibles .. but it's indicate a way to investigate more ....
Wonder what will be the final recommandations (to Airbus-AF and responsible bodies .. DGAC .. etc ...)

If ice is the trigger for a fault in the function of static ports, what sort of evidence does that leave behind?

I can't recall any event where static icing was implicated and would be surprised to see icing problems at the static location if that be on the aircraft keel surface. As to evidence, like most icing, the evidence of a single event melts with the ice ...

The 737 proved that it wasn't as longitudinally stable as the 727 (unlike the 727 you couldn't rescue a fast approach by throwing the gear out early)

Saved more than a few hot/high approaches (don't we all love ATC track shortening ?) by reconfiguring early - if necessary back to final approach configuration well out to improve the descent angle to something better than a mile a thousand. Or have I missed your point here ?

I wasn't going to make that distinction, as it's not important to the point I was making (early-life crashes that highlight airframe "quirks" are often written up as pilot error), but if you want to make that call, then go ahead.

I was referring to a document I read on 737 handling back when I had time to muck around with sims (the document referred to the real 737 however) - from memory it said something about some pilots trying some of the tricks they'd used on the 727 getting a nasty (albeit recoverable) surprise when they tried them on its little sister. I'm pretty sure "throwing out everything except an anchor" was one of those tricks...

Since your link dates from January 2011 and since we have seen no serious trace of that 'audit report' since... I don't quite understand what we are supposed to make of it.

I'm pretty sure "throwing out everything except an anchor" was one of those tricks...

All my jet time is 727/737 and I can't say that I recall any problems in this arena save that the 737 required more planning due to its useless speedbrakes - the 727 was a much more readily versatile aeroplane ..

DozyWannabeDid I say anything derogatory of Airbus, or imply a BEA cover-up? I can't see where I did. My comment was that the article in question had singled out Air France and the crew as being responsible before the BEA has released its final report - a long way off (time wise) methinks.

So don't get me wrong DW, I am not bashing Airbus and never have. My comments were reflecting the content of the article.

CJ - Agree.

Retired F-4, as a fellow Phantom Pflyer, I think we both appreciate that it would likely take 10, 000 feet and more to recover AF447 from its deep stall. Until the AOA was reduced, it would not accelerate, and it would take a bit of time to run the trim down far enough to recover. If the recovery took more than 20,000 feet, it would be because the nose was left down too long after it began flying. Availability of airspeed in the recovery would be very beneficial (since there is no AOA gauge .)

PJ2, AF447 may have been a bit 'goosey' at altitude but to actually get and keep the nose well in the air as AF447 did implies more a lack of awareness (scan or instrument problem) than a control difficulty based on the limited information released. (There seems to be no indication of a dynamic departure from controlled flight for example.). There seems to have been adequate control authority to put the aircraft in a level attitude.

More like PF expecting the aircraft to take care of pitch attitude without the need to scan while attention is diverted elsewhere. Of course, this is just my personal opinion, and I await the BEA interim report to shed more light on what is presently poorly understood by those of us on the outside.

thank you for detailed explanation A33Z

so in case of wrong CAS, MACH or ALT datas, what may be the result or the following aktion for the the FE Weight or Ceneter of gravity computation ??? in which direction will he put the wrong datas in his calculation? will he start pumping more fuel back or forward if the bird fly in level 350 with a (mayby) wrongly indicated CAS <255 ?

Machinbird;

Thanks, I don't disagree frankly. I'm just trying to find something outside the box to figure out why someone would point an A330 15deg NU and keep it there at FL350+ and these papers got me thinking. I've flown the aircraft at altitude and I must say it was pretty responsive in pitch and roll in Normal Law. I've always doubted the notion that the airplane was slow and 'slushy' to respond to the stick at altitude and that a bit of PIO or inadvertent backstick while controlling roll resulted in an "accidental" climb that continued to 38,000ft but I'm outa ideas!

...Me too PJ2! I hope BEA is able to get to the crux of the problem. The CVR will be key in this.

@Grity:
 

Quote:

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In Flight:

The FMGC uses the weight and center of gravity from the FCMC (Fuel Computer) when available.
The GW and CG computed by the FE part are used:
– as back-up in case of dual FCMC failure.

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http://takata1940.free.fr/fcms7.jpg

My apologies - as I have said many times, the man or woman who invents a "tone-of-voice" reader for internet forums will make themselves a fortune...