Lyman

Whether or not the a/c was reporting it, we are only sure of the crew's cognizance at 2:10:16. That is eleven seconds to be in the dark as to what is wrong.

Loss of Autopilot does NOT mean fly "PITCH AND POWER". It means fly...

You continue to studiedly ignore what RR and myself, among others, have pointed out, that the a/c was not clearly indicating that UAS was the problem, and that the computers did not necessarily include the crew from the outset of suspected duff speeds.

The reference is to what the a/c displayed, RESULTS of bad data.

Question. If the a/c had ceased displaying IAS from the outset of suspected bad speeds, would not the pilots have had obvious cue of loss of Airspeed (literally)

Displaying any cue that is known to be false is counter to good design, if said cue can be left out.with impunity.

Why waste precious time in a situation that is easily remedied with Pitch and Power?

The fact that pilot started handling the a/c demonstrates his belief it needed handling, period, speeds or not.

Hunter58

CONFiture, i lived in that particular country for five and a half years, and I am more than happy for every day I left it. However, that will not blend over the fact that once the HALs decide they have insufficient info he shows you what he does not understand anymore.

OTOH, Air France by now managed to be the first to wreck any Airbus since the A320, typically by not following procedures. You seem to be French, you should not be suprisd by such culture...

Oh, any anyone who believes Airbus is French has not lived there.

DozyWannabe

It also means "don't pull up". The correct response was to observe and then correct as necessary.

Even with RR_NDB's DSP algorithm, it would take time to work it out. Whether the system reported UAS or not is not the issue, the issue is and has always been the tendency to pull up when startled

The PNF had a handle on things at approx 02:10:15 though - as I've said before this flatly contradicts the idea that the aircraft was providing confusing information. I don't believe the PF pulled up because he believed in the protections, nor because he was unaware that UAS was the problem - he did it because he freaked out under pressure.

An instant appraisal cannot be done - even RR_NDB's hypothesis would still take a few seconds in order to work reliably. There's nothing to indicate that the PF's pitch inputs were an attempt to regulate airspeed - except for the response to the PNF's "Watch your speed" comment, which could have been taken from groundspeed. At that point, the PF actually briefly put the nose down, but then pulled it up again within a few seconds.

Detecting UAS is difficult, and the Airbus system is more conservative than most, disconnecting AP at the onset of the potential problem. Compare this to the Birgenair B757 where the autopilot continued to try to fly on the bad data.

In this case, it looks like the startle effect took precedence.

But it doesn't mean his belief was correct. The right thing to do was to monitor the aircraft's attitude and correct *only if* the attitude started to creep towards abnormal.

OK465

Exactly...and is that 2:12:44 time for ADR DISAGREE an ACARS downlink time, or an ECAM appearance time?

jcjeant

Under what pressure .. that of the the panic?
Panic because the autopilot disengages at cruising altitude?
If this is the case .. it says a lot about the criteria for selection of pilots and particularly on the selection made by AF
BTW it's not only on Air France !

DozyWannabe

Disagree - even top-drawer pilots mess up when taken out of their comfort zone.

infrequentflyer789

Exactly - and "fly" is what they did not do. The question is why.

If we assume that incompetence (never trained how to fly the plane) and negligence (knew now to but failed to) are out, then something caused PF to seek 10-15 degrees pitch up. Your (and RR and others) premise is that lack of precise indication of UAS from the outset is causative, right ?

So... perhaps you could humour this non-pilot and fill in the blanks, because I still don't understand how you get from:

- A/P has gone off, I have control
- Plane needs handling
- Plane hasn't told my WHY A/P dropped out

to...

- I need to pull up 10 degrees in cruise (even though that would normally be a crazy thing to do)


The only thing I can think of is airspeed indicated erroneously high (very high) - but that didn't happen, it went erroneously low.

So, what was it ? What piece of garbage information presented to the crew could have lead to that response ?

jcjeant

Autopilot is now the comfort zone of pilots ...

infrequentflyer789
How you can assume this is out ? .. on what basis ?
Remember ... Bonin ask (or dunno) what is St Elmo fire ...
Even a uneducated poor fisherman know what is St Elmo fire .....

Lyman

infrequentflyer789

Hello. "And fly is what they did not do..."

The autopilot was actively maneuvering until it quit, at handoff the a/c was rolling 4 degrees per second to the right, the nose was low, and they had exited moderate turbulence in conditions that I submit were more of a challenge than they were acknowledging, at least to each other, if not to themselves. If Bonin had not arrested roll, they would have been banked fourty five degrees when Robert said "So, we've lost the speeds..." eleven seconds later. In the eleven seconds I submit Bonin was unaware of UAS, his Pitch was not "full back" in fact it included several ND excursions.

Much has been made of "Do nothing". Not possible, given the conditions. Once Bonin got responses in Pitch (Was it sluggish? "Beware unusual control responses") he could easily have lost his sense of attitude. He was always the one flying, and his Panel was not recorded. What did he see and what was he using for references for his inputs? I don't know. At one point, PNF "Put him in ATT/HDG."?

Had he been using IAS? For the longest time I have defended this pilot, and I will not stop, though I do have to admit some strange examples of "pilotage" have shown up in other accidents (Colgan) (Schiphol) (Caraibes) and incidents.

Without a complete disclosure of the CVR it is impossible to know exactly what happened in the initial 20 seconds, the phase when the die was cast. I think that is deplorable...

My recent post addressed the fact that erroneous Airspeed was displayed. I consider that unfortunate, yet Dozy says it is unavoidable.

If IAS can be lost temporarily without risk, dump it until it can be verified. Given the state of the industry and the apparent lack of readiness to fly manual at altitude, nothing should be left to chance.

mm43

It is the ECAM appearance time of NAV ADR DISAGREE, and the ACARS received time was 2:12:51. Allowing 4 secs for the up/downlink, that would give 3 secs processing between CMC and ACARS. The previous message via ACARS was received at 2:12:16, which indicates the ACARS system was probably clear.

OK465

Which out of sequence message(s) do you think the report is referring to, if any at all?

Lonewolf_50

Dozy, talkin out your backside again, are ye?
You make an overly broad assertion, which is far more accurately stated as:

Some high performing pilots (call them set A) make errors when taken out of their comfort zone.

Others don't. Why? They adapt to unexpected changes in their environment better than the set A pilots do. Why? No short answer. If you could bottle it, you'd make your fortune many times over.

Have seen this through personal observation over and over again.

Lyman

Temp Temper Temperament. Better to bottle "cool under Pressure".

It is in the Amygdala.

CONF iture

As usual, when out of argument, you're back to Habsheim with a deformed analysis which is supposed to be mine.
Educate yourself on my view once for all - It's here.

Hunter58, as the instigator of the Big red X over the speed scale early in the sequence at AP disconnect, here and here, would you give a hand to Dozy who put his trust in you to locate such reference in the BEA reports ?

Linktrained

I cannot know whether this was the case :
IF PF had seldom ( if ever) manually flown an A330 - except premeditatedly for a very few minutes after T/O and again, just prior to Landing, both of these at low level, it would be natural for him to be startled.
The Drill for UAS (then) empathised Terrain clearance.

On earlier, less sophisticated aircraft, I soon learned to hand fly through Cbs, IFR and at night, before radar was available. St. Elmo's Fire and lightening strikes occurred. And my knees got wet because the windscreen leaked until a blanket was made available ! I logged my first 250 hours of hand flying, sometimes doing a couple of 3 hours sessions in a day, alternating with the Captain. ( My quality did deteriorate - but there were no flight time limitations, then.)

Hunter58

CONFiture

The BEA does not loose a single word on the representation of the speed tapes. If mentiones mesured speeds only, and focuses on the representation of the ECAM messages. There is no reference on whether there was a visual clue of the rejection of data via a cross (as it should be in that case) or not (which could be interpreted as erroneous data).

Obviously this factor was not worth a detailed description, which I believe is not a good call as there would be no discussion about it. However, since the speed values seem to have been rejected, this would have triggered the cross.



I am sure you can clarify this to our satisfaction, or would it trouble your picture of the supposedly corruptive power of a certain aircraft manufacturer too much? However, since you seem to at least have been in France once you should remember that such power would be extremely limited as every little local politician with ambitions would try to grab national attention by disclosing whatever information he has available. There are no secrets in 'La Grande Nation', the are simply too may elements ready to disclose them for their own short term publicitary benefit...

Lonewolf_50

Hunter, I inferred, perhaps incorrectly, that the pilot's remark "we have lost the speeds" was a response to an indication failure of his airspeed indicator, which I presume, also perhaps incorrectly, would be something like an "off flag" or "red X" or other marked change in presentation.

It may have seemed far too obvious a detail for the BEA to dwell on?

If I am off the mark here, please advise.

CONF iture

Maybe time for you and Dozy to pay another visit to the BEA report as there is a paragraph named Analysis of the airspeed displayed on the PFD’s and ISIS.
The SPD flag (There is no such thing as a big red X) which replaces the speed scale, was not displayed before 02:11:40

bubbers44

Personnaly I think Dozy is one of the smart guys in this group. I think he believes as I do that it doesn't matter what aircraft you fly, if the IAS goes away just fly attitude and power. That is what the autopilot was doing until it disconnected so why change anything. I don't care if Airbus says go to climb power and 5 degrees up in their situation, they didn't even do that, they pulled up to over 15 degrees for no reason and the PNF let him. Bad. Do we need the old timers to come back and teach them?

300 hr pilots flying on autopilot for a thousand hours are not real pilots. They cause crashes like this because they can not hand fly and trust automation to bail them out. When automation fails they are lost. AF proves it.

TTex600

If the autopilot didn't have adequate info to fly the airplane, what makes you think the pilot had any better?

It's easy to second guess from the rocking chair.

I would have second guessed from my MD80, but now I fly an Airbus and there but for the grace of God go I.