jcjeant

Can someone explain clearly why the BEA released only excerpts ?
Is there a law that prohibits the BEA to release the entire FDR ?
Is there a law that prohibits the BEA to release the entire CVR (transcript) ?
If there were leaks in the press and the publishing world (Otelli) BEA can only blame himself
If the BEA would provide comprehensive and clear informations (instead exerpts) .. journalists would not have to resort to some practices for gather informations (leaks)
Hide informations from the public .. how it's called ?

Clandestino

Retired F4, those remarks I made are not in any way personal and are absolutely meant to be general - i.e. applicable to anyone. I am sorry if you felt offended but here the offence is strictly in the eyes of beholder. Most of your questions have already been answered, too bad that besides having open mind, answers also require considerable foreknowledge of matters aeronautical to be understood. Somehow I don't think the answers given don't support the theory of "making sidestick input based on G feel".

Can we agree on that bending the facts to suit pet theories is not bound to be particularly productive if our aim is to truly understand what really happened?

The only thing I found in your post that has not been answered yet:

Airbus FCOMs & AMMs, 2.5/-1G clean.

I have absolutely nowhere stated that I've found the reason for AF 447 catastrophe, claiming that I wrote so is severe misinterpretation. I've put forward theory I think currently fits with the facts as we know it. If anyone have a facts that are contrary with it, please post it, it's not about proving my or yours or anyone else's notion. It's about finding what is right, not who is right.

If this investigation gets wrapped up with "Pilot pulled for reasons undetermined" that would be a real failure. What made him pull must be brought to light.

Who gives a part of a rat that the tail is attached to about what I think? This is the way our local universe, with its laws of aerodynamics, is structured. Yo want to go fast, high, far and heavy? It's a no-go without powerful THS. DP Davies book "Handling the big jets" has excellent treatise on why we need powerful stabs and how to handle them. Brief summary:If you suddenly got an idea that the aforeqouted sentence somehow validates your notion that autotrim is lethal, a) perish the thought b) read the following sentence. Theorizing about particular features of any design without knowing and understanding the basic principles behind it is extremely unlikely to be meaningful. Not limited to THS. Not limited to aviation.

My apologies, I keep forgetting that these are open fora so I have to keep discussion dumbed down to high school level for everyone to understand. You seem to understand that my statements "I do not fly by feel" and "I try to fly smoothly" contradict. Well, it is just not so. I do try to fly smoothly but not by the seat of the pants but by making small, measured inputs and crosschecking their effects against that big, bright attitude indicator in front of me. Leveling off without lifting the pax off their seats is best done by making small pitch change rate and that is done by looking primarily at the attitude indicator, crosschecking with altimeter and vario. Definitively not by using vestibular sense - it is last guard telling you you're doing something wrong but inflight it cries "wolf!" too often. Every instrument rated pilot must know the technique and use it, especially those who made it to widebodies, e.g. Airbus 330.

I would suggest reading Edgar Allan Poe's "The Purloined Letter" for an answer to that.

Not much is hidden, especially not the salient parts. The inability of some to recognize what is in plain view is quite ordinary but combined with their penchant for airing conspiracy theories gives spectacularly amusing results.

jcjeant

Hi,

Clandestino
Salient parts are only parts of the truth .. not the entirely truth

Condorcet
Paradoxally

Clandestino
Are you sure that the facts you know are all the facts that know the BEA ?

aerobat77

"What made him pull must be brought to light."

i think it will never be. the pilot will not tell you why he pulled and any data recordings can only answer what he did, not why he did this.

jcjeant

Hi,

The actions of a man (supposed normal mentally) are always the results of a thinkink
To make this thinkink that will lead to his action he must have facts to analyze
Recordings (voice and datas) can show what facts he had
If his actions are inconsistent with the facts available to it .. one might conclude that his thinking was not good, or as a last resort .. it does not have all his mental faculties (were altered) during the thinkink
So .. if we have all the datas who were available to this pilot .. we can conclude if is thinkink was good or bad
So .. yes we will know "why"
It's only three answers to "why"
Bad thinkink
Good thinkink relying on bad datas
Mentally disturbed

jcjeant

Hi,

Maybe it was already explained in many messages ( I don't remember anyway)



Why this difference of (displacement) movement of the elevators in reaction of pratically same movement (displacement) of the SS ?
Seem's that in the first 20 seconds .. the SS movements have not perceptible effects on the elevators ....

DozyWannabe

At a rough guess, I'd say as the airspeed goes down, the greater the potential deflection of the elevators to match the orders being issued from the sidestick...

jcjeant

Hi,

DW
So the deflection shown by the elevators is not the direct result of the position of the SS but instead .. (a filtered order) a position commanded by computer orders in relation with the speed
That can be weird .. as we know that the problem was a unreliable speed due to pitot tube problem ....

Lyman

BEA have quantified that. They have not established a reason for it, however. I believe the THS was moving, though. "Initially the a/c did not respond"...

Zorin_75

Uhm, no. There's a control loop feeding back the a/c response to the FCCs. No weirdness involved.

DozyWannabe

I suspect they're using different inputs to work out the aircraft trajectory/velocity than air data, otherwise there's no way that Alt 2 would work with ADR DISAGREE. In fact I suspect that the data they're using to work it out (probably inertial) formed the basis of the BUSS design.

CONF iture

Looking at the selected vertical speed trace, one of the key thing I'd like to check is the AP/FD vertical mode trace - I personally do find it disturbing it is not published yet.

HN39, how would you justify the vertical acceleration trace in the Perpignan case has never been published ?

A33Zab

It was explained before.
During the first part the actual normal acceleration (Nz) was > 1G and during the second part the Nz was < 1G.

CONF iture

Old Carthusian,
Your mantra is KNOW YOUR MACHINE but in the meantime don’t want to hear about technical stuff … ?

Equation is simple : If a type is repeatedly exposed to unreliable airspeed indication at cruise flight level, the manufacturer has to be aggressively proactive by publishing at least a safety bulletin addressed to all operators with a clear procedure to be followed if needed and to recommend all operators to train their crews for such eventuality.

When you have practiced once you are so much better equipped.

bubbers44

Every Boeing I flew had an unreliable AS chart for weight and altitude to hold a pitch setting and power setting. What these pilots did when they lost AS and autopilot was not anything remotely close to what the Boeing chart says. Everybody knows you can't pull up over 5 degrees at 35,000 ft in an airliner and still fly.

Unfortunately this is the new way of hiring pilots out of flight schools with no experience. We still have plenty of experienced pilots but they won't work for2,000 per month.

bubbers44

I know they were flying an Airbus 330 but the attitudes to maintain level flight are about the same. I went out of my way in my career to only fly Boeing AC. Had to fly MD80's for a brief period but that was just so I could marry my now wife of 21 years because of geographical problems flying the 727.

Old Carthusian

CONF iture

If you bothered to go back and read the previous threads (around 3 or 4 I believe) you would find a discussion of Airbus' procedure for UAS. It existed but wasn't used or even consulted in this case. The question is why? A stall warning was ignored for a very long time, again why?
This is not the fault of the manufacturer as much as you may wish it to be. This accident is a result of the actions or lack of them of the Flight Crew, nothing more and nothing less. The important thing to examine is what led the Flight Crew to act in the way they did and then to consider what can be done to avoid future occurences.
The suggestions that somehow you can attribute the accident to the autotrim or the lack of a yoke do not conincide with the transcript of the CVR or the FDR. They are missing the point which is psychological. This ironically is more difficult to understand than simple mechanics and aerodynamics. However, we may postulate what led the PF to take the course of action he did but we will never know for sure. The one thing is if this accident induces AF to improve its training and procedures the loss of life will not have been in vain.

HazelNuts39

CONF iture; I don't recall having particularly missed it when reading the report. Anyway, this thread is about AF447.

HazelNuts39

The response of the airplane in the first minute is shown in high resolution on pages 41 and 42 of Interim #3. Something odd struck me in the 'simulation' traces on page 42. According to the associated text, "it was agreed that, initially, the simulation would be confined to the longitudinal axis, without introducing turbulence." If the simulation is without turbulence, what caused the variations of alpha prior to 02:10:05, without noticeable variations in pitch, V/S and Az, and why did the elevator move after 02:10:00? Why differs the THS position from that recorded?

CONF iture

It is good observation HN39.

• Also why simulated elevator position shows signs of oscillation movement already before 02:10:00 ?
• Why that time period is not represented in page 41 graph ?
• Why only left elev is represented ?
• Do left and right elevators really move together or graph on P108 could be better … ?

"Airbus conducted a simulation of the aircraft behaviour based on the theoretical model and on the actions of the PF (sidestick and thrust)."
Why not then represent PF's actions (sidestick and thrust) on those P41-42 graph ?

Correct. But investigation led by the same investigation body and again some data of interest are not published.

In a few words :
Why does the Judge withold data from the proceeding ?