AF 447 Thread No. 8
 

AF 447 Thread No. 8

Thread part -

(a) #1 starts here and finishes here. Posts = 3890
(b) #2 starts here and finishes here. Posts = 2537
(c) #3 starts here and finishes here. Posts = 2071
(d) #4 starts here and finishes here. Posts = 1061
(e) #5 starts here and finishes here. Posts = 1978
(f) #6 starts here and finishes here. Posts = 1683
(g) #7 starts here and finishes here. Posts = 1354


Links to the various BEA reports are given below. If I have missed any of the useful papers, please PM me with the URL and I can include it.

(a) BEA site - French, English
- Report link page - French, English

(b) Interim Report (No, 1) Jul 2, 2009 - English

(b) Interim Report No. 2 Dec 17, 2009 - English
- Update Dec 17, 2009 - French, English

(c) Estimating the wreckage location Jun 30, 2010

(d) Wreckage search analysis Jan 20, 2011

(e) Briefing and associated update May 27, 2011
- Briefing - update French
- Briefing - update English
- Briefing - update German
- Briefing - update Portugese

(f) Interim Report No. 3 July 2011 - French, English

Miscellaneous pertinent links -

(a) Airbus Operations Golden Rules
(b) ALPA FBW Primer
(c) C* and Civil Transports - Cranfield
(d) Longitudinal Flight Control Design - RAeS
(e) Longitudinal Stability: Effect of High Altitude and CG - Boeing
(f) pitot static system performance - USN (Pax River) FTM
(g) The Problem of Automation: Inappropriate Feedback and Interaction, Not Over-Automation. Donald A. Norman UCSD
(h) Upset Recovery - 16MB zip file
(i) Ironies of Automation. Lisanne Bainbridge UCL
(j) Cognitive Capability of Humans. Christopher Wickens Uni Illinois
(k) Trust in Automation: Designing for Appropriate Reliance John D. Lee, Katrina A. See; Human Factors, Vol. 46, 2004
(l) Training for New Technology. John Bent - Cathay Neil Krey's CRM site


Search hint: You can search PPRuNe threads with a filter in Google by using the following search string example -

ths af447 site:http://www.pprune.org/tech-log/

This will search for mentions of THS in the AF447 threads of tech log only.

Just change the THS in the string to whatever you want to look for. This allows one to search for any term or phrase of interest throughout the threads.

Adding the site:URL end part is the magic that restricts Google to only searching in Tech Log.

This filter technique is absolutely wonderful and can be used generically to find things of interest in PPRuNe - appears to work OK in the PPRuNe search function as well.

In respect of Google searching, JenCluse has added some suggestions -

a) indenting the text block with a (one) Tab, *and*

b) emphasizing the fact that it is a search text block with some manner of . . .
<SearchText>, or
"SearchText", or
?SearchText?, etc

• But it is not : "On n'a pas une bonne annonce ... de vitesse"
• It is : "On n'a pas une bonne annonce ..." 4 seconds later "... de vitesse"

The BEA wants to link those two pieces of the CVR ... I don't think they go together.

What would make more sense is : "On n'a pas une bonne annonce ... (de decrochage)" just following l'annonce "STALL"

1. The OSV info told them to not pay too much attention to spurious or even continuous STALL WARNING.
2. The Air Caraibes memo (if they read it) said that the crew righly disregarded 2 inapropriate STALL WARNINGS.

Later on the ON/OFF status of that STALL WRN without any notable change in the aircraft state confirmed to the crew that something was definitely wrong with that warning.

Also, as it is a new thread, I don't want to lose what was part of the previous one.
Beside the sidestick there are other concerns as :

• the THS
• the STALL WRN
• the WRG message
• the zipper shape of the selected V/S trace BEFORE AP DISC

These subjects must be fully addressed before reducing the investigation to three unfit pilots ...

What is "... de vitesse" linked to?

I agree with your (1) and (2) on stall warning. RE: the Air Caraïbes memo - Airbus could have more strongly opposed the Captain's 'intime persuasion'. I.e. the warning was "appropriate", even if it did not require specific action in the circumstances.

May I suggest introductions again?

I'll start. I'm a US FAA certified narrowbody Airbus Captain with experience (DC9, not AB) in functional check test flying.

Ttex600 wrote:
Good idea!

And I am a nobody who knows nothing (except what I've learned in this fab forum) who also pushes almost as many buttons as you guys do when I play my Hammond B-3 organ. (Yes, we get flying sometimes.) When I get confused/lost/push the wrong switch, I live to tell the tale.

Always wanted to fly. Never could afford the lessons. Been following jet transport issues since the early 70s. I really appreciate being allowed to hang in here with you experts, and occasionally contribute all I can bring to the party: good common sense. :p

British Gliding Association (BGA) safety committee member, some experience of gliding accident analysis, current glider pilot and lapsed PPL.

I cannot claim any knowledge of CAT flying, but I do know something about glider flying and gliding training, and also something about gliding accidents and what surviving pilots have said on occasion.

And the reason I followed this from the outset through all threads – when a stressed pilot forms the wrong conclusion, he/she tends to stay with it regardless of ineffective attempts to correct the wrong problem. I have seen this in my field (gliding safety and accident analysis) – only test pilots, or rare individuals, can keep a clear head and systematically fault find.

K.I.S.S.
 

The "model we are assembling" since the crash matches to your comment.

:ok:

I personally had few incidents where this was observed. I started the observations 50 years ago and with maturity, experience and training (to develop methods) the "clear head and systematically fault find" was possible. And worked (and works) very well. In different types of machines sometimes in extreme and dangerous situations. Problem is when "things happens fast" Your chances dim very fast if initial solutions not the best. Fortunately i always had chances. Invariably staying "ahead". Even "ahead" i faced a surprise testing a car 19 years ago. (At night, light rain, concerned with a family member disease and a subtle hidden fault in a tire, aggravated by a little error :E).

ChrisN:
Things like, "Blimey!" and "Holy S***!"?

:}

As I hinted at in a post near the end of the previous thread, I have put together a customized Google Search Engine that will find your Search Term in an individual PPRuNE AF447 Forum thread, or if selected, in a search of all of the threads.

The Google search engine returns pages containing variations on a search term, e.g. the term 'site' [without the quotes] will also give hits on 'position, location' etc.. While a term in quotes, "tcas ra occurred before" will return hits only for pages that contain that term exactly.

There are, or have been 13 substantive PPRuNe Forum threads covering the total AF447 event saga, and one small one I found started in the Jet Blast Forum when the initial Air France A330-200 Missing thread was going 'mad'. The above search engine covers those threads that have made their way eventually into the Tech Log, plus the original Air France A330-200 Missing thread which remained in the Rumours and News Forum and was closed.

Joined the fray just after the crash. Just interested in any FBW plane that has a problem. Thot I could learn something and maybe pass on some lessons-learned from the genesis of FBW flight controls.

Flew 600 +/- hours in first operational FBW jet from 1979 to 1984. Was staff puke or would have flown a lot more. Total time 4,000 hours +/- in F-101B, F102A, A-37A/B, A-7D and F-16A/B. 600 combat hours with about 400 combat missions.

Systems engineer after retiring from USAF.

Considering it is just after the PNF comment "On a perdu les vitesses" it could be seen as an ackowledgement for the unreliable airspeed status, but in first intention "On n'a pas une bonne annonce ..." was IMO specifically directed to the STALL warning, not the speed.

Where I do ask questions following the Air Caraibes memo is here :
The memo is 6 months prior AF447 - As a Manufacturer Airbus has many ways to communicate directly with the crews all over the world to dispatch safety information but nothing was done for that matter.

To answer TTex600 suggestion :
Very much interested in accident reports, try to learn from other's mistakes before I do them.
Looking for the full story not only the convenient part.
Have no trust left in the BEA but everybody knew it.
Flying for close to 25 years, 12 on the 330, but flew Boeing too.

I would say that none of the issues identified by CONF iture are actually of major importance in the cause of the accident and some can be said to be irrelevant. The cause of the accident is unfortunately the flight crew who did not respond in an appropriate manner to the situation.
I also wonder about all this mistrust of BEA - surely this is misplaced especially as the courts are involved? Having read several BEA reports they have always struck me as models of professionalism

Introductions
 

Actively investing in 2 Projects working as manager and R&D engineer.

Started professional career in aviation in 1970 and since then addicted to the multidisciplinary characteristic of this industry.

Was introduced to the anatomy (and it's subsystems) of old birds when 17 years old. (Connies, B25, C47, C46, GA, etc.) in a A/C scrap shop.

EMI/EMC specialist and HF radio operator since 1972.

Main objective (agenda) here: Aviation Safety through Synergy with people.

Mac

Extra interest: Be (in a proactive app.) prepared to better understand "She". (A/C, machines in general and also women :8)

Why? Because it's safer. :} (The surprises could be better "managed") :)

The global picture is important for possible future cases*
 

When investigating EVERYTHING must be considered. The final report is to be released. So we can ssume the investigation didn't finish yet. CONF iture listed possible contributing factors that could together represent important elements to the result.

It seems, but need more information to say this We just don't have all "inputs" they received. And we don't know everything the machine "presented" to them. (to the crew).

It seems to me BEA could do better (just before Paris air show).It seems difficult to have all steps done at this time. It seems they became vulnerable since then.

Let's wait (being prepared to) to see the Final report.

* As you know, an accident statistically has multiple factors involved. Frequently the trigger is not a crew error. And a prepared crew could in many cases, save the day. And the opposite is true: :sad:

@CONF iture:
 

IMO you can skip this concern from the list.

The 'zipper' means it is - not active - (AP was in ALT HLD mode not in V/S mode)
You can notice identical 'zippers' to est. slide slip trace - after law change - de estimated slide slip is not calculated in ALT LAW.

The selected MACH trace - Page 109/110 BEA IR#3 EN - shows the 'zipper' too.
This trace for whole flight @ page 110 shows dark area but actually these are 'zippers'.

Also 'zippers' on the other parameters related to AS when these were NCD.

Why - the not active state - is reflected as zipper I don't know, maybe due to a reset signal to distinct from a steady 0 value?

RR-NDB
It seems to me that a post in response to Lyman is relevant here. Sometimes it is necessary to look at things x1 not x10,000. This is the case here. Ruling out the options is a common process in an investigation. The issues here would revolve around certain individuals' wish states not an objective look at the actual circumstances and occurences of the accident. It is also possible to be too sceptical and too cynical - if it looks like a duck and quacks like a duck chances are it is a duck. There is no need to invent other reasons for what is an accident based on pilot reactions, lack of adherence to SOPs, poor to non-existant CRM, no designated chain of command, training issues and possible cultural issues within Air France.

CONFiture has a point, and it's a good catch!

I can think of several words to use to describe the "visual" display of speed in French, but none of them would be "annonce", as "annonce" implies "sound". Indeed, the association of "annonce" with "de vitesse" makes no sense, or a lot less sense, than the association with the "Stall Warning", as the speed was NOT communicated using "sound", while the "Stall Warning" was.

O C may have been fortunate in his selection of pilots. All appear never to have been wrong.
Admittedly prior to CRM, I must have flown with more than a hundred airline pilots, some of whom learned from their own and doubtless the mistakes of others - possibly even some of mine !
My first CFI was the Chief Test Pilot of a Midlands aircraft manufacturer who would not allow me to go solo until I could stall and spin - and to recover !

Later I was to fly with perhaps eight graduates of the Empire Test Pilots School who had decided to become long-haul charter pilots. Two of them thanked me for teaching them to be First Officers. (By implication this had not been in their syllabus.) Both were kind enough not to say that they had learned from my bad example. ( I had myself, learned from watching a few bad examples over the years, the York captain who swung off the runway onto boggy grass by harsh engine handling, or the Captain who applied brakes when only the nose-wheel had landed !)

A look at the report on F-WWKH show what CAN happen with a well qualified crew anticipating and by day.

Perhaps he is saying...... "The airstream sounds wrong"

Not bad airspeed, but wrong "speed of air". The airstream sounds quiet, or too fast?


If so, the two separated phrases still belong together.

"...announce de Vitesse...". Is it his first declaration "crazy speed?"

　

If the pilot corrects the wrong problem, or if response is not appropriate, it means that the effective aircraft is NOT OBSERVABLE to him : not enough or not the good sensors and data to analyse the situation, or wrong connection in HMI (human machine interface partS, first of all SOPs, CRM, training, selection, health, etc.).

I say it never enough : To work a dynamic system has FIRST to be observable and controllable. Stability, sensitivenes, robustess, optimisation, price, etc. come long after.

We have to accept the difficulty of the BEA's work, living day and night with the crash.:}

At the trials, reference to the Annexe 13 and the good use of the recommandations has to be said by pilot's unions. It would be the best way to help the BEA to do the safety problems OPEN.

In the forum we don't do another trial, nor another BEA report : we are together to get better, communicating in a larger point of view that the BEA is allowed to do.

@roulishollandais

I say it never enough : To work a dynamic system has FIRST to be observable and controllable. Stability, sensitivenes, robustess, optimisation, price, etc. come long after.

Observable and controllable. Yes, but respectfully, this is a bare minimum.

This is (must be) the state at DEGRADED. Whilst in cruise, the system, no, the interface, must be INTUITIVE, No? Unremarkable and fluid "get" without Stopping to think.

Thinking takes time, sometimes too much. Here is the fulcrum of the issue, as the system is challenged, reversion in mechanical and Human actions must be synonymous, and synchronized. No time for independent reversion, the machine into less control, whilst pilot reverts to "abstract". The partnership should not degrade whilst facing rarities, it must grow closer. Confidence and continuity come first, always. How Stone Age to stop the flow, retrieve a handbook, and start to study......

No Lyman... that's twisting it to non-sense....

"annonce" is like in the typical "voice announcement" of a train arriving, or leaving a railroad station, or an airport terminal station..

As a Frenchman, pilot of AB, how would you say: "Sounds Fast" ?? How could he be commenting on Sound, and speed, unless CONFiture is dead on?

IOW, how to say: Noise inconsistent with IAS?

@Lyman

I have the distinct feeling that everyone is trying to read too much into the 'reported transcript' of the CVR.

Why? Because even with the short phrases that are being debated, the intonation has been lost in the transcription, and the BEA had the advantage in hearing the intonation and being able to help by adding 'linkage words' that weren't necessarily there. Let's face it, the ambient cockpit sound in which the words were spoken will have impacted on how the transcript was presented in the French language.

One can only but hope that the translation from French into English was peer reviewed using the same background knowledge - but probably not; and the reason for this debate.

mm43,

I agree with you. When the adrenaline is flowing big time as it must have been in this event in these moments, words may not flow smoothly as one is multi-tasking at the time.

In the AA DC-10 event in Chicago, there was one word on the CVR, Damn! That was it. Wonder how that translates into French...

:ok:mm43 TurbineD

Fellas. I know you both too well to think your comments are intentionally patronizing. I know what I sound like, and readily concede I am looking under every stone. As my flight instructor said (ref: checklists), "leave no turd unstoned".

Four seconds after STALLWARN, and PNF "What's that?" PF says, "We have a bad announcement..." That means sound, and that also means STALLWARN, given the indexed chronology supplied by BEA. So a bad announcement may mean "Decrochage Faux...." Maybe not. By now, the adrenaline is still in the coolie hats atop their respective kidneys, they are cool.... I will keep that bit of information aside, but will not reject it. Notwithstanding the apologetic tone of you two guys, trying your best to put a happy face on......what?

:D

two much.....

Lyman,

Your version of "leaving no stone unturned" is commendable, and I'm not in the business of being patronizing.

However, this debate around what was said and what was seen by the pilots, is the very reason that the BEA wants mandatory recording of RHS parameters along with a "look" at what these guys should have been seeing. No doubt the BEA are confused by the actions taken and the words spoken when the recorded FDR LHS data shows something else.

Trying to recreate what was actually on the RHS PFD is fraught with danger.

• It can be assumed the same was available on the LHS PFD, but
• Was the PNF on the same page?
• Neither of the pilots referred to any discrepancies between PFDs, and
• The PNF was aware (at times) of what the PF was doing and commented when required.

Should data have subsequently been recovered from the QAR, I believe we would have heard through some 'leaky pipe' by now.

I am also unable to understand why the PF was able to look at an overly blue PFD and not accept that he was in fact "attempting a climb to the stars".

So, there you are. Was the RHS PFD overly blue??

@mm43

"So, there you are. Was the RHS PFD overly blue??"

I have to say no, and guess that it showed some horizon, and a nose between 3 and 9 degrees UP. They were satisfied, reasonably, with the sitch til Stall. No screaming, no yelling, no snatching the SS. "We have the engines... So...".

What neither of them saw, anywhere, was AoA. Up to and through the actual STALL, there was no mention of doom. "Let's hope we're climbing, we are at four thousand."

Hyperfocused on loss of altitude, they had not noticed the Stall, would you? Nor had they any reason to mention anything, evidently. I frankly do not believe the data, as released, can lead to rational conviction of PE. Failing the release of all data, and I am a hard sell, to be sure, I think "Cause unknown" is as good as any. We don't know why, only what, and that is insufficient. Absence of evidence is not evidence of absence of care, or competence, it just is not.

My pea brain says even though they had nose up, and knew it, they could not get to "Stall..." only to: "push the Nose DOWN? Are you nuts? Look at the VSI!"

Ciao :ok:

How much blue? At 02:10:18 when the PF says "On a pas une bonne annonce de ... vitesse" (how many seconds to pronounce that sentence?) the Pitch Attitude is 11 degrees NU. The PFD then looks like this:
http://i.imgur.com/nB2BR.jpg?1

From the video posted here.

My point is this though - we can trust the information released by BEA and that their investigation will be fair and correct. I also understand the call for more transparency but they do have more important things to consider than keeping people informed about every little phase of the investigation. All that will happen is that the organisation will be delayed by queries and nonsensical comments from outsiders. Given the amount of comment that has already gone on on this topic without any conclusion one way or the other is it surprising that BEA are taking a long time. There is a lot to consider in this accident even if the basic causes are already known.
roulisholandais
I like the point about not observable but this is just one possible aspect of the problem which may in fact not be significant. It may be that the pilot himself is making the aircraft not observable and the available evidence actually points to this being the case. Given how many A330s, 320s, 340s are flying around without similar problems one has to think that indeed the flight crew were the main issue not the machine. I would expect many more accidents if the machine was a problem.

HazelNuts39,Exactly! At FL370+ why?

We will never know.:sad:

mm43

The altitude was barely above select cruise, @ 35.3k. @ 2:10:18. So my question might be: only 35,300? Why is this a/c climbing so sluggish? I don't dispute the Pitch picture, but it didn't match with Alt, necessarily, after ten seconds of climbing. The video catch does not represent the dynamic nature of the trends?

HazelNuts39

It was ".....annonce..................." " ........de vitesse......." Not ".....annonce de................". "...........vitesse....". Four seconds between annonce and de. Annonce and de are separated, not together.

PF was inputting ND three times at 2:10:18, and airspeed shows 70 knots, and we don't know if the displays were consonant with DFDR. A/S is duff, else he Stalls here...... He is comfortable with this Pitch, yes? What does that say? If it is what he sees, after all.....


I will ask my French expert re: " annonce". Besides, STALLWARN is a result of speed plus AoA, could he not mean "Stall 'vitesse' ? Not a reference to AirSpeed, but a ref to StallSpeed. Did he have the StallWarn bug present on his tape? Why is speed tape missing from video snatch? I believe his comment refers to a bogus StallWarn.

Your comments are most appreciated, it is quiet on my "side". :ok:

As you mention, the selected MACH trace shows also a similar 'zipper'.
But my question has been here all along :
WHERE is the AP/FD vertical engagement mode trace ???
That trace would tell if the 'zipper' is irrelevant.
In the meantime that trace is central to figure what were commanding the FDs when displayed.

Why such trace is missing ?

It is inexact to state so ... The 3 pilots were reading attitudes, vertical speeds, altitudes ... but at no time did we hear - PULL - PUSH - DONT PULL - STOP PULLING - YOU PULL TOO MUCH ...

Only in final despair, under GPWS warning, came up a - TIRE TIRE TIRE -

Sidesticks at their best ...

I thought thought the zipper was doing nothing more than a resolution issue with the data ie the lsb switching on and off and nothing 'real'.

"Old Carthusian"
 

I really hate to say something so personal in public, but it needs to be said:

OC's posts all seem to be written entirely from the point-of-view of Airbus. No room for any possible factors other than pilot error. Seems preposterous to me that anyone would insist that it was just that simple. Unless I learn otherwise, I'm assuming that these posts are generated by someone at AB. (OC's profile is entirely empty. Who was that masked man?)

If I'm wrong, I am sure I'll burn in hell.

Organfreak;

Does it matter? I'd welcome Airbus participation in the discussion on this thread.

Better to remain silent and be thought a...