RR_NDB

Quote:

If you want climb now you're going to put us in a very dangerous situation that's why I will limit your ability to climb

Why not limit the climb (zoom climb, ballistic climb, any climb) above REC MAX?

Simple programming, easy to inform the crew, hard limit IMHO important to avoid entering a very dangerous space where you could stall and LOC your plane.

Why not? This would be over automation?

Simply put:

You must have authority to control your plane. Always. Specially during anomalies of any type.

jcjeant

Hi,

Confi_ture
Sensitive subject !! ... minefield .. contaminated with viruses of conspiracy ... ghosts that lurk .. case closed for justice .... post mortem analysis highly discouraged ...

RR_NDB

Hi

DozyWannabe

I've got a lot of time for Ray Davis, and read that he did exemplary work trying to get to the bottom of BEA548 back in 1972 - which was no mean feat given the lack of survivors and lack of a CVR (In fact the recommendations made by his team were what eventually made CVRs mandatory in G-registered transport category aircraft).

Airbus wasn't knocking him, despite how you're trying to frame that statement. They were pointing out that he had been retired for several years before he took the case on. You can't bring a doctor back after an extended period of retirement without first familiarising them with the advances that have happened in their absence - so it goes with accident investigators.

No, he wasn't. For a start, Flight Recorder data is not "encrypted", it is encoded. On the old analogue gear this was as a series of voltages and on the newer digital boxes as a serialised sequence of binary data.

Ray Davis was a brilliant investigator, but he didn't really understand how DFDRs differed from their older analogue counterparts, which led him to make several erroneous conclusions about the tapes, which are explained at length in the article Franzl posted.

Yes - only painted by the pilots. They diverged from an already shoddily-put together flight plan because they missed the turning point for the airfield, then elected to expedite the descent rather than turn around and start the approach again - letting the engines spool down completely in the process (fatal mistake no.1).

They made the decision to disable A/THR completely to proceed with the display. As PJ2 said, the narrow, short runway may have fooled them into believing they were higher than they were. This prevented any chance that the system could help them out of their predicament (fatal mistake no.2)

In this case, no. I've already said that if Alpha protection had not checked Asseline's attempts to pitch up that the aircraft would have stalled and more would have died.

Clearly - sometimes - yes. This isn't a criticism of pilots as a breed, just an honest acknowledgment that we all have bad days at the office.

Funny that an allegedly "conveniently buried" issue has already been brought up at least three times in the course of discussing AF447, an incident which bears no relation to AF296 in any way, shape or form on a technical or procedural level.

RetiredF4

You are lokking for that one?

Davis

Most of the conspiracy stuff is here:

crashdehabsheim

CONF iture

Thanks a lot RF4 !
The last time I visited that site, a while ago I admit, the original English version of Davis document was not there, only the translated French version was.

You know, nowadays the conspiracy idea is always raised when people are looking to NOT debate a subject - It is getting all too convenient.

I just can't stand anymore reading DozyWannabe uninformed erroneous and false comments on Habsheim.

There is matter to discuss on Habsheim, I'm looking for that.
Of course the level of credibility and independance of the BEA will be chalenged ...

When time permits I will start a thread called Habsheim.

Lyman

Distract, Damage, Muffle, Marginalize. The answer is always patience, and some element of good fortune, or a change in fortune of those who hurl "Conspiracy".

The thing I do not get is the animosity toward scepticism.

Patience, Persistence.

The hook in this report will be the conversations, cockpit. Habsheim made a fertile field for loss of reputation, no doubt. Who will guard the guardians? The mere appearance of a conflict should provide a judicial special master, or ombudsman, one would hope. The Public interest is superior to bottom line.

imho

DozyWannabe

I think you'll find everything I said backed up by the investigators, the courts and and every aviation agency in the world. Your argument is predicated on the paranoia of a mentally ill ex-AF Captain who went to bat with Asseline and ended up ruined.

In the immortal words of Jack Nicholson, "You can't handle the truth".

Lyman

Damage, Distraction, Marginalize. Next comes Muffle.

KBPsen

Lyman,

Have you considered that people are just fed up with your continued attempts at disinformation and manipulation of the known facts? The picking and choosing, taking things out of context and ignoring others.

The only saving grace would be that you are simply not able understand the subject and/or are a confused soul. I suspect that is only partly the answer.

CONF iture seems to heading down the same path, sadly.

jcjeant

Hi,

DW
Urban legend ...
Sorry DW .. but this Captain was not mentally ill .. and that's not my opinion .. but it is the medical reports that attest after examination by experts that this pilot was not mentally ill
Those reports are available on internet
It surprises me that you did not know that .. saw the interest and knowledge you have of the accident

Turbine D

I think you are intertwining factual information with personal opinions. Here is why:

Quote:
Your quote
Nowhere does Airbus point out what is in bold in your statement, that is your interpretation/personal opinion. Mr. Davis challenged the BEA report, particularly that of the recorded data.

IMO, that left both the BEA and Airbus no choice but to discredit Mr. Davis and his technical challenges, and they did. Much was at stake for Airbus, a new airplane, new concept for flight controls, first airplane delivered, a public demonstration and public conjecture that the airplane was at fault. It was important for Airbus to rebut, emphasizing the aircraft performed as designed. In the same way it was important for the BEA to rebut as they were under much heat for a perceived "botched & biased" investigation by the media and others, erroneous or not. This happens all the time in the courts with either the prosecution or the defense attempting to discredit a knowledgable expert witness and it happened in this instance.

Your quote

IMO, I don't see a shouting match at all, there were only six short vocal exchanges three by the F/O, three by the Captain once they reached 100 ft., the last comment by the Captain coming while descending into the trees.


Originally posted by RR_NDB
Your quote
IMO, the bold in your statement is supposition for something that didn't take place and therefore can't be confirmed one way or another.


Originally posted by RR_NDB:
Your quote
IMO, this gets back to the philosophical FBW debate, your opinion, not a fact.

Your quote
IMO, there are always overarching fundamentals, whether they be familiarity with and understanding of the aircraft operating systems, training, improvements and or changes in basic written operational instructions that may differ from one incident to another. Nevertheless, there are relations from this aspect or point of view.

RR_NDB

This may be the reason we find sometimes difficult present arguments to DW.

TD probably characterized something useful to be considered by DW and some other participants.

I think it's important to distinguish facts from personal opinions and put both clearly separated.

E.G.

I personally have as a Electronics Designer serious objections against several "resources" (including protections, etc.) used in aviation today. When questions, issues and facts are presented to us it's important to hear, to analyze, to study, etc. before.

Sometimes we must criticize. I made this against the FALSE REDUNDANCY of using 3 Pitot's that stistically fail near simultaneously. I called it ridiculous. The responsibility is not small when we make this. We must check redundantly and then, need to be assertive.

Assertivity without careful analysis is dangerous and can cause problems and confusion.

PJ2

DW, re your post #694- "[nitpick]Alpha floor protection, to be precise (the thrust component). Alpha protection, which is a flight control function and affects pitch and bank, remains active at all times in Normal Law IIRC[/nitpick]"

Thank goodness I don't have to remember the nitpicky stuff any more. Thirty-five years was enough.

Lonewolf_50

For Lyman:
Yes, odd, even though I have seen something very much like that in real life previously*.

I repeat my guess regarding what is behind that non-reaction: SW presumed spurious due to known airspeed spurious input. That said, simply paying more attention to "tasks x, y, and z" may render the audio input less compelling.

*Two (of a number) things I experienced IRL to do with warnings ignored.

A. Late 80's. Night training flght. Safe for solo check, me Instructor, one Student. Standard arrival VMC, night, final landing. Task: simulate "you have an engine oil high temp, low pressure" (engine oil leak drill). Student chooses correct response: climb to high key then set up for a (power on, training) dead stick landing profile. Which he did, except ... (this is at night, warning lights tend to be brighter in the cockpit at night) when he got to high key (~ 2500 feet AGL) he dropped the flaps rather than the gear and began his turn.
This gave him multiple warnings:
Caution light flashing (he'd turned on the landing lights),
flashing red light
loud and annoying warning horn,
He reported to me "three down and locked, landing checklist complete" and proceeded into the turn for low key (which is the abeam / 180 position) for a dead stick landing profile. He reset the Master Caution ... but didn't fix anything else.
I allowed him to continue, figuring he'd catch his configuration error and fix it at the 180. He approaches the 180, calls tower, reports three down and locked (all three indications were up, all warnings still going off) and continues.
Tower clears him to land.
He hits the 90, roughly on profile, (a bit high now, as he should have gear and flaps down already) and reports to me "gear down, flaps down, checklist complete" and begins a gentle slip (a technique taught for altitude control in the dead stick provile) to get his final better matched to profile.
All lights and aural warnings still going off.
I direct him, as he turns to final, to wave off / go around. (IP wants to preclude wheels watch shooting flares at us at night).
I call tower "Wave off, request left Low key" as the student obediently waves off this approach, and tried to raise the gear.
And now, the icing on the clueless cake.
"Sir, the gear handle won't go up, are you holding it down?"
(Instructors would occasionally guard gear handle to avoid certain errors, overspeed gear, etc).

My reply: "You never lowered it, which is why you can't raise it any higher than UP, A---. I have the controls."

I cleaned up the aircraft, took it to low key, performed the rest of the dead stick profile, and landed the aircraft, emphasizing to him the absence of the warning horn, absence of warning lights, and absence of anything odd.

I had flown with him before, and he'd usually gotten things in the right order. I had been his instructor on his first night flight, and he'd flown that same profile correctly then. What struck me was how the warning at night are so much more noticeable, and he never seemed to "see" them.

For whatever reason, he went brain dead and exposed a tendency to report things by rote that he wasn't doing. (Bad idea) No solo for him.

B. Year 2001, me pilot under instruction (referesher training) and my experienced IP has the controls. Day, VFR, return to base for final landing. Pilot enters the break nicely, gets to the 180, calls 3 down and locked (and I check, seeing the handle up and indicators up, and flaps going down) and he calls tower, three down and locked, for landing permission.
I say
"T---, the gear handle is still up, as are the wheels, and that warning horn is kinda loud."
Pause.
Wheels go down, flaps stay down, we review the checklist complete together, agree we have three down, and we land safely. (He buys at the club that afternoon, needless to say. )

From novice to experienced pilot ... it can happen.

What makes me so confused and so sad is that it seems to have happened to both pilots on the flight deck in AF 447.

That is why I lean toward an internal dialogue inside each head "with airspeed unreliable, stall warning must be spurious."

I could be very wrong, and it may be some other thing, or a bunch of other things.
Altitude display was not known to be manfunctioning, nor the attitude indicator malfunctioning. (Slight unknown, but no strong direct evidence for)
From info reported, PNF's attitude indicator was for sure working.

HazelNuts39

If PF didn't notice stall warning, what caused him to select CLB, then TOGA, go to 15 degrees pitch and actively maintain that until the airplane dropped out of his hand after 40 seconds?

DozyWannabe

Norbert Jacquet ended up several lettuces short of an allotment. He paid the "medical experts" (actually university professors) to refute that assertion and then spent the next few years putting together a website filled with ever more paranoid claims that the French aviation industry was out to get him.

As a rule, that suggests a level of paranoia and mental instability considerably above the norm to me. "Here's the reason I was blackballed by my country's aviation industry to protect a dangerous aircraft design, and by the way here are three experts who have all concluded I'm not mad" is not exactly an introduction to inspire one with confidence.

@TurbineD

I wouldn't say I'm threading opinion between documented info - it's pretty obvious that Ray Davis's conclusions come from a lack of understanding regarding digital flight recorder information storage. This isn't me knocking him, this is just a fairly straightforward conclusion. Think what you may of the source, but pages 21-38 (original) of the Airbus rebuttal posted by Franzl go into considerable detail to explain it.

Also worth pointing out is that the BEA and Airbus rebuttals were separate entities and there was no collusion in producing the documents - the BEA invited Airbus to provide their own given the technical expertise on the DFDR technology they were using.

Maybe "shouting match" was an extreme description, but there is a definite increase in volume, intensity and interpersonal conflict from the moment the crew spotted the trees on the CVR.

The "philosophical" debate on FBW and protections aside, I was simply providing an example where the protections *did* in fact save lives from the actions of a captain who on that particular day turned out to not be as infallible as he thought he was.

CONF iture

I think it is all about the FDs coming back at that time in V/S mode. The PF happily finds something to follow ...
Before AF447, TOGA was the correct answer to a stall warning, but 15 degrees of pitch was not part of that procedure.

During that period, the autotrim silently helps him to follow that foolish FD command and gives him the illusion to be in control ...

A few elements could now make us think the pilots intentionally discredited the stall warning.


Would you add to your graph the FD, V/S, SEL V/S traces if possible ?

HazelNuts39

There are some practical difficulties with that, and I don't see the point. On page 111 the V/S Sel equals the V/S and page 91 IR#3 states:

Lonewolf_50

HazelNuts39, your question I don't have a simple answer to.

Caveat: the following is an attempt at analysis, not any sort of "truth" about what happened.

Let's suppose that the stall warning (created by the sustained "zoom climb," which is a matter of either scan breakdown or perhaps an internal decision to use nose to control speed to avoid overspeed ... ) triggered the "low altitude stall warning" response, which might be described and depicted in your graph, albeit with a nose attitude not set and held very well.

1. What stall warning ought to trigger is a decision to reduce angle of attack, particularly when stall warning happens at cruise altitude. It didn't. Why is that? Unknown. (Estimate: In part, I don't think either pilot had a sense of the AoA of the wing. I also wonder at their training regarding "high altitude stall, high altitude approach to stall.")

2. As the warning sustains over time (50-60 seconds) the control inputs do not show a trend of AoA reduction based upon your graph. The overall trend is to climb toward limits of performance envelope (if not into it). What seems to be going on in the cockpit is that the pilot who took the actions you describe is not getting the result he expects.

(Expectation: "If I go to CLB and TOGA, I should fly out of this stall warning.")

Note: his / their response at cruise altitude (with a lower altitude set of procedures) isn't the response one would expect. (Do I hear the Pitch and Power Chorus warming up in the background?)

At some point in that 50 - 60 seconds of response, I conclude a cognitive mismatch:
"What I am doing to treat stall warning is not curing my stall warning sympton."
This could lead to internal conclusion that "A/S is unreliable, this stall warning is unreliable or spurious since what is supposed to fix it didn't."
Further stall warnings, when they come back on well into the stall, are ignored during the period when a potential remedy (nose down, fly out of the stall, begun somewhere above ~ 12-15000 feet?) to stall could be attempted.
The signal "stall warning" is never converted into either pilot's awareness "you are stalled" realization. I believe that if PNF had diagnosed "we are stalled" he would have said so to the PF.
(From my example, my flight student never converted "lights and warning noise" to "your gear are still up" realization.)

Back to AoA, which is measured but not displayed. There is no AoA gage to consult as a cross check. Neither pilot seems to have considered digging down through the pages to get a look at AoA. (Memory hazy: is it seven button / page actions to get there? PNF would need to do this, PF was behind the aircraft and trying to fly it). Given their task loading gradient and apparent misunderstanding of what is going on, I am not surprised that PNF didn't go head down in search of AoA on the pages. Were AoA a primary concern, the actions we see evidence of on the traces would probably have been different. Also, when captain at last arrives, would his glance at an AoA gage help him say "{Merde!} You are stalled, do x, y, z, etc." Don't know, maybe yes.

So there you go: if not initially (your point is taken on that score), then at some point subsequent, the stall warning was either
dismissed as suprious
or
ignored due to "what is it doing now?" problem solving/confusion overriding aural cues.

@ 0210, 47 sec.
That appears, from your graph, to be about six seconds before CLB TOGA are chosen. Did I read your graph correctly?