KBPsen

Yes I do, but not selectively.

The BEA probably knew that there would be people who would apply their own selected meaning to anything the BEA would publish. So they also published this.

Lyman

BEA: "....and the pilot applied NOSE DOWN INPUTS and alternately left and right roll inputs..."

Did they get it wrong?

Lyman

The graph shows F/O Pitch commands. The PILOT FLYING was flying from CAPTAIN's seat?

I'll leave it to you to sort why the comments don't jive with the graph. For now.

Know that vertical speed does not represent altitude, or "CLIMB"

DozyWannabe

Could just as easily be a glitch in the FDR data though - which can have issues with sampling sometimes and after all had spent the best part of three years on the bottom of the ocean. The regularity of the missing data samples suggests a read/write failure rather than the value actually being read.

Even so, I'm sure I remember seeing Airbus pilots post that they don't tend to use V/S select all that often, and in cruise there'd be no reason to use it. If it's not referred to in the final report, write to the BEA and ask for it - it can't hurt.

Lyman

At this point in the flight, DOZY, the a/c is in autopilot.

KBPsen

After all this you still haven't figured out who was PF? Not that it is surprising.

Only in your mind. How to sort that I have no idea.

The graphs are there for all to see. Perhaps you should start having a look so we can be free for you home baked "facts".

Lyman

The graph and comments are self evident, and conflict.

DozyWannabe

@KBPsen

Perhaps you'd like to explain the difference between SELECTED and MANAGED mode on the A330's FCU - and at the same time how the use of the word "and" is equally valid for simultaneous events as it is for sequential events - in fact to imply the latter tends to require the phrase "and then".

Lyman

Then show where on the graph AoA ten+ is.

Machinbird

And having given the hamsterwheel another spin, Clandestino goes off snickering down his sleeve.
Welcome back to the hamsterwheel Clandestino, did you miss your old friends?

mm43

Please clean your monocle!

The BEA Interim Report No3 actually said,
That was in relation to the initial climb, but during the second phase the SW activated at AoA 5.9°, AOAmax was passed at 7.6°, and CLmax 'break' occurred at 9.6°.

This graphic should help.

Zorin_75

KBPsen

That such basic concepts and use of language needs explaining boggles the mind, but then I doubt it needs to be.

It is the deliberate misunderstandings and misrepresentations, selective use of data and the mixing of a sliver of fact with handfuls of fiction that needs explaining. If it is even possible.

CONF iture

Zorin_75 and ChristiaanJ,

Beside the conspiracy theorists, anything you could bring to the subject ?

AlphaZuluRomeo

Ahem... BEA's interim #3, §1.11.2
No trace indeed, but unequivocally written : "Le vol est effectué sur la route prévue en modes ALT CRZ / NAV."
"The flight followed the route envisaged in modes ALT CRZ / NAV."

I'm perfectly happy, for myself, with Clandestino's posts. Shall I ask him to marry me?

Joking aside, I also would like to know why the selected V/S varies so much (and so regularly) before AP disconnect. I think (guess) it is a "normal" behavior but would like to have a confirmation by knowledgeable people.

DozyWannabe

This is an educated guess rather than certain knowledge, but based on what I've learned on the subject of data analysis (which is actually part of my professional remit - lest CONF think otherwise) those negative peaks are at such regular intervals that I suspect that they are unreadable values rather than reflective of the actual setting, as I said here:

http://www.pprune.org/tech-log/46062...ml#post6741729

Given that it looks like they've used Excel to generate the graphs for the interim report, I know that Excel's default graphing behaviour for unreadable values is to render them as the lowest possible value (in this case -5000).

Now, whether that value would be unreadable due to corruption of the memory chips from damage sustained, whether the memory chips were faulty in the first place, or whether there was a pre-existing fault on the FDR bus that meant that the value was incorrectly read is something I'm not qualified to speculate on.

Ultimately though, if we can make a reasonable assumption - based the BEA's statement that the flight followed the ALT CRZ/NAV mode - that the flight was indeed in that mode up to A/P disconnect, then the V/S setting should not have had any effect as, if I recall correctly, the MANAGED mode does not use V/S as a parameter.

ChristiaanJ

CONF, I thought the somewhat 'odd' V/S SEL recording had already been solved, either earlier in this thread, or in one of the earlier threads.

infrequentflyer789

I have, I guess I just don't see what you see in the traces.

I have been looking at the graphs with expanded timescale - which show the time we are interested in. P29-31 of the report has useful graphs but without gridlines so it is difficult to be precise, P42 is the best for that - it doesn't have pilot input, but we know from P29 that this begins at 02:10:07.

From graph on P42 I reckon at 02:10:07 we have pitch = 2, THS -2.8, VS maybe -300. Then at 02:10:10, pitch = 4, THS -3 (started to move), and VS maybe +300 (ie. started to climb). Pitch 10 degrees is not till a bit after 02:10:16 by which time VS is already +5000.

It looks to me to be moving to follow elevator trend, with a delay, a rate limit and a stop, not much more complex than that. At some point I might try and digitize the traces and try and extract the rule, but it looks right. It also matches the sim results (see P41).

Page 29 - A/P drops 02:10:05, "I have controls" at 02:10:06, stick goes back 02:10:07, 2secs delay. I don't see the stick going back to pitch neutral awaiting response either.

Further, the response tracks simulation, so the a/c was responding as PF should have expected. If we ascribe his actions to unexpected a/c response, then we are back to the question of why doesn't PF know what to expect from his a/c, are we not ? [and is it PFs fault if he's never actually flown (been allowed to fly) his a/c in cruise ? - no]

If there's a windshear procedure that calls for 15deg pitch and TOGA in cruise (at max alt) then I would respectfully suggest that it is a recipe for another disaster. No ?

On the pitots, I think I almost agree. There is some evidence (audio ascribed to icing), and there is the experience of all the other flights - but not totally conclusive.

The worrying thing to me is that I can't see anything that connects the PF actions (cause of stall) with pitot failure specifically, or even uAS specifically. If he climbs to arrest a (real or perceived) altitude loss, or inadverdently while focused on roll, then pitot failure is not a required cause, and fixing the pitots will not prevent a recurrence. UAS may make the recovery less likely - but speeds were actually valid again by the time they stalled, and stalling a big jet is big trouble regardless.

If the triggers for the PF climbing his a/c into a stall were only: A/P drop out, Alt Law, and turbulence (maybe), then we have a big problem, because Alt Law / A/P drop could have lots of causes, and is an expected condition at 1 in 10k flight hours (I think). That is more than a little worrying.

infrequentflyer789

AFs procedures at least are clearly confusing since preople here can't agree what they mean even with plenty of time to read them.

But, turning it around slightly, what evidence is there that any procedure was bring used ?

The quoted (confusing) procedures I have seen all have AP & FD OFF as first actions - and this was never done (AP dropped itself, FD remained selected on).

Turbine D

Hi
Infrequentflyer789

Not only does AF's procedures seem confusing, AB's procedures don't seem to me to be much clearer. Below is a briefing (2006, may have changed by 2009) as to what to do with an occurrence of UAS. The briefing was to identify new procedures as the airlines were confused with the older procedures. Of particular interest, note how UAS is highly referenced and dealt with during cruise at high altitudes and high speeds.

It's not that the crew of AF447 did everything right, it's what they may have been taught or not taught, remembered or not remembered for the situation they found themselves in.

Take a look and tell me what you think.

http://www.iag-inc.com/premium/Airbu...ableSpeeds.pdf