jcjeant

Hi,

This forum is titled "Tech Log" as it is normal that all the technical assumptions are discussed here.
Many hypothesis have been advanced .. so that even someone qualified can be confused by their number and diversity.
There's just a fact that caused all these technical discussions .. it's the pilot performance in the first seconds after the autopilot go off
This in my opinion is the most important fact
Does this fact is explained by all the technical assumptions in posts?
I doubt it strongly.

Just a tought
They have this chance .. but they already begin to ruin it by the release of their last note.
And this chance was again badly wounded by the statement of a member of the french political body (Mr Mariani directly involved in the following of AF447 cause his position in the government)

DozyWannabe

Wallybird, you're right!

However, I don't see anywhere in the post you quoted where I referred to "blame". I was very careful in the word I chose, and said "finding", using the language common to the AAIB, NTSB et al.

Well, glad that's all sorted then - back home, lads!

Seriously though, when they've got facts worthy of release - I suspect they'll release them. It has long been common practice in aviation accident investigation to cover as much ground as they can so that as much can be learned as possible - that's the reason it tends to take a while.

For example, the AAIB's final report on the BA038 incident took 2 years and one month to produce. In that case, they had the entire airframe more-or-less intact, both flight recorders and the QAR to hand, as well as the entire crew and passenger list available for interview - but the lack of evidence regarding icing on the heat exchangers meant that there was a significant hole in the available data and thus there was a seemingly "inexplicable" element to the incident. The BEA produced their initial interim report on AF447 with small fragments of wreckage, a set of ACARS messages and no flight recorder data. Now that they have more wreckage and the flight recorders they are probably going to have to do a lot of rewriting of their assumptions, as well as a whole battery of human factors testing in relation to what they've learned from the CVR.

As an aside, the discussion on BA038 on here went back and forth for those entire two years, and speaking for myself I learned a lot of new and surprising things from that discussion - but at no point did any contributor demand that the raw data traces were released or chide the AAIB for not doing so. Now was that because it was the AAIB doing the investigation and not the BEA? Was it because the aircraft involved was a Boeing 777 and not a member of the Airbus FBW family? Or was it because there's an understanding that these things take time and should not be rushed. Being on here for as long as I have, I suspect it was a combination of all three.

Finally, there were theories doing the rounds (that ended up in the BBC/NOVA "Lost" documentary on AF447 back in 2009) that the thunderstorm cells were obscured on radar by a smaller cell in front of the cell they entered - what do you do in that situation if avoidance beomes impossible?

I haven't seen any evidence of this regarding Air France, could you point me in the direction of some?

"Badly wounded" how? They released all the information they could determine after just a few days looking at the data - just as the AAIB did with BA038. M. Mariani may or may not have been speaking with the blessing of the BEA (it wouldn't be the first time politicians have gone over the heads of their accident investigators - and it's certainly not something peculiar to France).

The problem is that there are some on here that remain wedded to the idea that the BEA will always try to find against the pilot before anything else - something that is not supported by any evidence gathered over the last 20 years at least. Yes, their paycheques are ultimately signed by an entity that has a controlling stake in the manufacturer and airline involved, but the same was true to some degree of the old UK AIB (in the days when the UK made airframes and BA was state-owned), as well as the NTSB prior to the mid '70s (Boeing/McD-Douglas and Lockheed were privately owned, but heavily dependent on government/military contracts).

hetfield

Dozy, that's a very good question! Like most of us know this can be a real trap!

Regards

Graybeard

Dozy:I just want to repeat that documentary was rubbish. Just reading the pilot's guide for the Wx radar on 447 would have given them real info about the radar capabilities. Instead, they went off on an ill-founded theory about the "storm behind the storm."

jcjeant

Hi,

I disagree about this
The note released it's just some fragments of the CVR record.
Unless the CVR had recording problems ... we can't tell the BEA released all the information provided by the CVR
This is why all those posts trying to fill the gaps open by this incomplete release.
If I quote one of your message incompletely .. you will complain of context .. ♫♪la la la♪♫
Same for a incomplete BEA release ....

RR_NDB

Hi,

They had time to carefully select and release the "right information" taking into account all all possible implications. Trying to secure a big and comfortable "room to maneuver".

Their text, lacking important details, seems typical of PR instructed to deliver "the right information" for that moment making easier for BEA to "navigate" the "turbulent environment". The lack of important details does not allow a more precise analysis. And this also may prove later to be against BEA mission because seems showing a preliminary bias with the emphasis on "NU from PF".

And in emphasizing persistent NU commands seems as to considering as the "major cause", coherent to LF leak, deviating the focus from plane malfunction(s). This was IMO a tentative to gradually prepare public opinion and timely to the big "interests involved in Paris Air Show". The seriousness because the LF leak was too early (IIRC in the Monday subsequent the first analysis during the weekend). Probably an opportunistic attitude from one(s) representing the huge interests" behind. With risk (and probably, intentions) in creating a "frame" for BEA "output".

Human machine interface issues, "software issues", etc. would be considered "machine faults"?

System processing of "ridiculous Pitot redundancy" has chances to be considered "machine fault"?

All this are "against crew" and makes easier the work of the "high rocks" at FR government and it´s personnel (including BEA top managers).

Most of us yet now could imagine the Report and it´s recommendations. Certainly BEA is "ahead of the schedule" on that.

They seems to be navigating very well in this turbulent weeks since wreckage location.

DozyWannabe

Read what I said carefully. I'm not saying that's what happened to AF447, but if that situation is a possibility then "Avoid all thunderstorms - period" becomes insufficient advice. What do you do about the thunderstorm you can't see?

Not really - a full CVR transcript is also out of context without an FDR record to explain what was happening in conjunction with the statements recorded by the CVR. What they've released is what they could determine by matching up portions of the CVR data with what they have extracted (and processed) from the FDR so far.

Case in point - I remember an accident described in the "Black Box" book* that accompanied the C4 series of the same name in 1996. The investigators in that case released CVR data where the pilots were complaining of being tired - this got picked up by the press and the accident was written up as fatigue-induced pilot error. Another angle they were working at the time was that the altimeter fitted to the aircraft in question was known to occasionally misread by up to 1,000 ft and there was plenty of evidence that this had indeed happened. As such, they recommended replacing that model of altimeter, but because public perception had already accepted the "fatigue" explanation, the regulator wasn't interested.

This is about the fifth time I've asked this question and I've yet to get an answer - why are there demands for raw data being made of the BEA in this instance from some quarters on this forum, when to my memory no such demands have ever been made of the NTSB or AAIB?

@RR_NDB : I note that when journalistic "tittle-tattle", as it applies to piloting and aircraft operations, is brought up on here it tends to be treated with the scorn it deserves, except in very exceptional circumstances. Why should press hearsay about the motivations of the BEA and the French government be any different? [EDIT : Just had a quick squiz on Google, and as far as I can see the "Paris Air Show" connection was made at the end of a paragraph in a Flight International article, and all that said was that the timing of the discovery "could have come out of a film script" - no connection to the possible release of information to protect Airbus or Air France has been made outside of the speculation on this forum.]

* - The book was heavily oversimplified and wasn't really all that - but my local Waterstone's was getting rid of it for 2 quid...

Turbine D

RR_NDB

Perhaps a more appropriate saying:

- Confucius

OK465

This was actually predated by the noted Far Eastern scholar, Wo Phuc, who noted:

"If you want it badly, you'll get it badly."

Graybeard

Dozy: What is the context of your question?

Was it that the AF pilots didn't receive adequate training in use of their Wx radar?

Was it that AF didn't upgrade to the latest radar that has special processing for tropical storms?

Do you believe there are thunderstorms with no rainfall or ice pellets?

DozyWannabe

@Graybeard : The context of my question is that if enough people thought it was a possibility, even if it doesn't turn out to have much of a bearing on the case, would it not be a good idea to look into remedying the situation - whether that be via training or technology?

I've got no answers to your other questions, other than a nagging suspicion that for all our knowledge, nature will always find a way of surprising us - sometimes not in a good way.

Turbine D

Thanks OK465,

That is the message, very concise.

CONF iture

Did they have any choice really when ACARS + Air Caraibes report were all over the Net … FIRST.

Framing the mind, correct, but better known as 'communication' or even better, 'information' …



Three lies in one single image :

1. People will think that what the pilot was seeing on his weather radar screen was exactly that big red area.
2. People will think that the pilot has intentionally penetrated that same big red area.
3. Why are not depicted both the aircrafts that have flown the same route as AF447, in the same big red area ?

DozyWannabe

Would they have done so if they weren't? That's a question neither you, I, nor anyone else can answer. I believe they would have (after all, it was pretty much the only information they had to go on and they had to base the first interim report on *something*). You may think differently.

That image looks a little... how should I say... "dramatic" for an accident report. It looks more like a sensationalistic press cutting to me - how are the BEA responsible for that (any more so than the investigators in other countries responsible for their press getting the wrong end of the stick)?

Let me know what you think of the stuff I PM'ed you!

JenCluse

To RR_NDB's (post 4/150), should be added Harry Hawker's suggestion to his designers:

"Simplify, and add lightness."

( I'll try to remember that, if I post again :~? )

hetfield

Wasn't there a LUFTI on same track as AF447 30 min ahead?

BOAC

I will repeat my opinion that the release by BEA was 'mischievous'. As I have said, they have the CVR and FDR. By limiting the CVR info they neatly 'imply' that PF pitched to 10 deg, and climbed 3000' (above optimum and possibly above max) without a single word being said by either pilot about it. Either that is the case, which I positively doubt, or there is some reason why this part of the conversation has not been released. It would have saved pages of PPRune. Without it we are all guessing in the dark

rudderrudderrat

Hi BOAC,

I don't think the BEA are "mischievous". The full official report usually takes months, sometimes years to produce. There was a thirst for a briefing as to what may have gone wrong, and the BEA released some information.

Something similar happened with the B777 at LHR 2008 pprune discussions. It's not the BEA who are mischievous - it's us - the pprune posters.

http://www.pprune.org/rumours-news/3...crash-lhr.html

HazelNuts39

... based on the entirely arbitrary assumption that the pilots observed the departure in pitch, v/s and altitude and discussed it, and BEA withheld that crucial part of their conversation, in the knowledge that they will have to justify that decision when they publish the transcript.

As a minor detail, BEA said : "The airplane's pitch attitude increased progressively beyond 10 degrees ..." (to 13 degrees according to my 'simulation').

Hyperveloce

The context of this note should be taken into account: the BEA was under pressure to anticipate their analysis of the newly recovered DFR/CVR, some results were leaked and Airbus was already claiming that the analysis of the recorded data had shown that the plane was not the problem. The BEA reacted strongly to this claim, making clear it is the only authorized entity to establish new facts about the AF 447 accident, that those leaked/unauthorized informations were not helping the families who had lost a relative, that it will soon release a first set of new facts derived from the recorders and an interim report by the end of july. A bone to gnaw, waiting for the main course.