Air Asia Indonesia Lost Contact from Surabaya to Singapore

[Chronus]

EMIT you make it sound as if they were a couple of amateurs in a sampan wrestling with their chop sticks in rough seas and wondering why their chopsticks would n`t work in the usual traditional way.

I did not suggest nor hint that ECAM failure announcements had anything to do with the wx. The only coincidence is that the whole thing went belly up soon after they took wx avoidance action. When it comes to air accident investigations should coincidences not be carefully examined.

[peekay4]

@EMIT

No one is saying Boeings can't stall or pilots on other aircraft types can't make dumb decisions. All of your "other accidents" are completely besides the point.

In both AF447 and QZ8501, the left seat pilot tried to apply the correct control inputs and were: 1) unable to do so; 2) unable to understand why; 3) unable to resolve the dual input situation until the end. The AirAsian Captain tried to take over control -- twice -- without success, and he clearly didn't understand what was happening and why.

With linked controls there would not have been ANY ambiguity of what was happening.

[EMIT]

Report

Chronus
I think that the investigation did examine the possibility and their (justified) conclusion is that weather played no part - i.e. FDR parameters did not show undue turbulence, which would have shown up as choppy acceleration traces, etcetera.

No, they were not amateurs, on the contrary, they were professionals. What I get tired of is seeing colleagues letting slip aircraft from their fingers time and again for no good reasons.

[peekay4]

@FDMII @ZFT

Under 121.423 FAA is mandating UPRT pilot training for all Part 121 ops by no later than March, 2019. This means flight simulators must be updated by that date to accommodate "extended envelope" training, and accordingly the FAA simulator standards + qualifications are being completely revamped. Final rule on the new standards is expected early next year.

[EMIT]

Peekay4
All the captain had to do, was push the override button to get full control. For that he did not need a DUAL INPUT aural - if he had used the override button, that warning would not have sounded either. The lights, indicating DUAL INPUT through their illumination, were not prioritized away by the STALL STALL aural.
Yes, as ex-Airbus pilot I know that the override button is hardly ever needed, so hardly ever used, but is an essential step to memorize when taking away control from your mate.

In a Boeing, it still takes more force than your mate is applying in order to override him. Will you intuitively know for sure whether you are just applying "unusually large or unusually strong" inputs or whether you are still fighting the other guy?

[Chronus]

Originally Posted by EMIT

Chronus
I think that the investigation did examine the possibility and their (justified) conclusion is that weather played no part - i.e. FDR parameters did not show undue turbulence, which would have shown up as choppy acceleration traces, etcetera.

No, they were not amateurs, on the contrary, they were professionals. What I get tired of is seeing colleagues letting slip aircraft from their fingers time and again for no good reasons.

In my humble view there can never be for no good reason.
In this incidence the timings speak volumes. An aircraft in the cruise and in the space of less than two minutes its gone ballistic up to 38,000 feet then mushed its way all the way down into the drink. All because the automatics have decided not to play ball. So the conclusion must be that the two poor chaps up front were imbeciles as they did not know which way to twiddle their sticks. I just don`t buy it.

[peekay4]

@Chronus

The P2`s question is in fact an expression of surprise. Does it not suggest that the the indicated responses he expected by the instruments do not conform to his actions. He is baffled and cannot understand why the situation is worsening.

The FO most likely had The Leans, a strong sensory illusion (disorientation) when an aircraft abruptly returns to level flight from an unnoticed turn.

See extract from pg. 48 of the Final Report below:



(guide numbers added)

1. FAC1 & FAC2 off, aircraft enters Alternate Law and started to roll 6 degrees / second to the left unnoticed (roll position indicated by sloping purple line)
2. FO finally notices the AI after nine seconds and, startled, makes abrupt right roll to level the aircraft. (Black/Grey lines indicate right/left aileron positions)
3. At this point QZ8501 is nearly level, FO relaxes roll inputs to neutral
4. FO is disoriented due to the leans, thinks the aircraft is now in steep right turn and quickly rolls the aircraft back to the left
5. The aircraft is back near the original 54 degree left roll position, which feels "level" to the FO

The FO was likely disoriented all the way to the ground. The Captain might have been less affected due to his different physical position and his previous experience as a fighter pilot.

[_Phoenix]

alf5071h,
I agree with your comments.
Either I, didn't find any reference to longitudinal trim in the report, nor in the FDR data. That's strange.

FDMII,
The THS trim position is a function of elevator movement and position, nothing else -> True, BUT elevator is not a direct function of sidestick position. In the AF447 FDR, PF pushed sidestick forward couple of times, but the elevator didn't rotate more than half nose-up and THS was at max nose-up.
Even without THS graph, I'm quite positive that is the case for QZ8501. maybe worse with apparently abnormal law triggered by AOA>30 deg, then THS was fix at max NU.

As the airplane's flight control system continued to attempt to maintain the commanded the low g-load, as the airplane started to sink, the pitch trim ran to full nose-up. From that point on, recovery may have been impossible unless the crew had the awareness to reduce that manually. Even with full nose-down pitch command, as the airspeed built up in the recovery the nose-up trim had too much influence to overcome and the airplane would pitch up despite any action on the sidestick.
Something fundamental has to change on this matter, for a simple reason: under stall it's imperative to reduce the AOA, if PF demands nose down rotation then A/C should start rotate that direction not opposite. How? engineers to figure out: THS position, moving fuel foward, etc

[FDMII]

EMIT, "All the captain had to do, was push the override button to get full control."

Yes. The last pilot to push the button retains control while the button is pressed.

Further detail from an AOM:

A pilot can deactivate the other stick and take full control by pressing and keeping pressed his priority takeover pushbutton.

For latching the priority condition, it is recommended to press the takeover push button for more than 40 seconds. This allows the pilot to release his takeover push button without losing priority.

However, a pilot can at any time reactivate a deactivated stick by momentarily pressing the takeover push button on either stick. If both pilots press their takeover pushbuttons, the pilot that presses last gets priority.

_Phoenix;

True, BUT elevator is not a direct function of sidestick position.

Yes, I know. I said this in my response to you.

Even with full nose-down pitch command, as the airspeed built up in the recovery the nose-up trim had too much influence to overcome and the airplane would pitch up despite any action on the sidestick.

Well, I don't think that claim can be made without the aerodynamic work behind it support the claim. The elevator in AF447 remained effective and could have brought the nose down.

Something fundamental has to change on this matter, for a simple reason: under stall it's imperative to reduce the AOA, if PF demands nose down rotation then A/C should start rotate that direction not opposite. How? engineers to figure out: THS position, moving fuel foward, etc

Regarding something fundamental having to change, no, I wouldn't think so, not, at least, until the assumption the statement is based upon is well understood and supported as per the above.

Regarding using the THS wheels on the center pedestal, the THS is always available mechanically. Moving it ND would have improved chances for recovery in both this, and the AF447 cases.

Regarding the moving of fuel forward, the notion is entirely impractical for the A330/A340 due the time it takes to do so, (20 minutes, roughly from full to empty), and technically not possible in the A320 as there is no fuel stored in the horizontal stabilizer and moving fuel in the wing-tanks inboard takes more time than any meaningful improvement to CG could be accomplished.

[ZFT]

peekay4

Under 121.423 FAA is mandating UPRT pilot training for all Part 121 ops by no later than March, 2019. This means flight simulators must be updated by that date to accommodate "extended envelope" training, and accordingly the FAA simulator standards + qualifications are being completely revamped. Final rule on the new standards is expected early next year.

My understanding is that UPRT training can already be readily accomplished on (most recent qualified) simulators now as this doesn't require any additional data. The only simulator update required is the "IOS Toolkit page". The extended envelope data is required for full stalls for which the current OEM supplied data is somewhat lacking, although just what is being provided is still unclear (to me).

[EMIT]

Control

In cruise in an airliner, for a cruise climb (that is, to the next useable level) you super duper machine has the performance only to sustain about one degree more of pitch. Yank the nose up more and you WILL loose speed (and continue doing that and you will stall eventually).

I can understand that in a startle reaction, a pilot might yank up the nose a bit too high (INITIALLY), but then very quickly he should realize from looking at his attitude, as indicated on his attitude indicator, clearly and unequivically, without any error or failure, if unsure, check the other guy's attitude indicator and the standby attitude indicator, all independant, extremely reliable sources, realize immediately that he has flown the aircraft into a not normal attitude and just correct the attitude to normal values, such as you stare at for endless hours during your whole career: the blue side up, the brown side down, dividing line between those colors approximately in the middle, wings approximately level - it isn't more difficult than that!

It is not a question of automatics not playing ball - when the autopilot tripped off, due to pilot action, the pilot flying did not start flying until 9 seconds later. That is a human issue, to not attend to your aircraft for such a long time, not an automatics issue.

Peekay4
The leans, exactly. Kind of funny, that the sensory ilusions (or failures of our senses) are used to make simulators seem so close to reality, but that apparently pilot training does not prepare you sufficiently for the real sensory illusions in flight.

[peekay4]

@ZFT

The new 121.423 requirement does include recovery from full stall, so as I understand it, this requirement can't be accommodated by current simulators (possibly except Flight Safety's new G550 simulator).

121.423:
(c) Extended envelope training must
include instructor-guided hands on experience
of recovery from full stall and
stick pusher activation, if equipped.

The reason compliance was pushed five years to March 2019 was to allow new Part 60 simulator standards to be published and implemented.

[Smilin_Ed]

I DON'T Understand

I can understand that in a startle reaction, a pilot might yank up the nose a bit too high (INITIALLY),....

I don't understand that at all. As I, and numerous other posters said in regard to the AF447 autopilot disconnect, the thing to do is NOTHING. In AF447, instead the PF hauled back on the stick and kept it there all the way to the water.

The pilot flying is supposed to be aware of everything in the cockpit. Making precipitous control inputs is exactly the wrong thing to do. Pilots are not supposed to allow themselves to be startled. In this case, leveling the wings was the first thing to do while steadying the aircraft in pitch in yaw. Apparently this guy was not really a pilot.

[EMIT]

Ed

I get what you mean Ed, the "understanding" for startlement is only very slight - I agree that a (real) pilot shouldn't get startled in the first place, but if he does, it should only last a moment and his normal, controlled state should immediately kick back in - obviously, that did not happen in all the high altitude stall accidents.

[ZFT]

peekay4

The new 121.423 requirements are noted with my thanks.

[steamchicken]

Does anyone know why the report says explicitly that weather was not a factor and was not analysed (in which case, how did they know it wasn't?), but there are multiple recommendations in the back about weather radar, cunimbs, participation in regional met. forums, and weather in general?

If they didn't analyse it, how are they making recommendations about it?

[peekay4]

Weather was analyzed. However, they found that it was not a factor in this accident so the weather analysis was omitted from section 2. (The weather conditions were included in 1.7.)

[alf5071h]

Phoenix, Re #3637 and your #3659, thanks.
Noting that the A330 and A320 have different aerodynamic configurations and apparently software, the AF447 analogy is reasonable; but as before, without trim data THS/elevator effectiveness and capability for stall recovery remains supposition.

FDMII #3643, Re THS, AoA, etc, agree:
However, to reemphasise that the THS (trim) is a powerful contribution to pitch control and if mis positioned can seriously detract from the elevator’s ability to generate a nose down pitching moment.

An interesting logic diagram, but if this is for ‘normally expected’ switching (including power failures), it may not include law changes due to power interrupts as supposed in accident – would the design logic anticipate switched ‘power failure’ and stall in that order.
Also, the diagram apparently does not show the switching for the Abnormal Attitude Law. This appears to override both Normal and/or Alternate Laws and freezes the trim; in ‘normal’ circumstances trim could be recovered when the abnormality is corrected (aircraft tending to recover from a stall – (even in Alternate?)).
Earlier questions considered ‘if’ Abnormal Law was triggered whilst in a forced Alternate state would the trim ever be recovered; if not then stall recovery would have to be made with abnormal control effectiveness (elevator +/- THS), … and abnormal rudder trim.
… now how many of the proposed sim training exercises required by FAA /EASA will include this?

Is anyone able to verify / comment on whether an incorrect seat positon - #3466, i.e. not at the design eye positon, will affect the ability to positon the sidestick to demand a quick roll response without an inadvertent pitch-up input? Noting that in the RHS, right roll and nose down requires the longest reach.
Perhaps some real simulator tests might determine the capability (likelihood) for a range of seat positons.
Also, consider similar problems for the left seat; and how quickly an appropriate seat positon could be achieved after leaving the seat (electric seat motor?).

Anyone remember all those years ago when just after rotate a Capt’s seat slid back because of the seat rail locking failure, and s/he could not reach the centre stick?

[xcitation]

Perplexed

I am forced to accept the initial miscommunication "pull down".
What I cannot accept is how the FO, a french pilot would block out the grim similarity with his stick inputs to AF447. Surely FO would have read and discussed the AF447 reports several times so I am incredulous that a french pilot on similar type could ignore his grim replay. I did not read in the report if they look into the psychological background of the FO.
At a minimum I would expect FO to confirm response like "stick full back at the stop, pitch up". Then at least every 30 secs "maintaining nose up, stick full back". In the absence of call outs the capt should have ordered them.
Is there a need for a tightening of regulatory standards to improve flight crew cross communications?

[Organfreak]

Do pilots study crash reports?

xcitation's question

Surely FO would have read and discussed the AF447 reports several times so I am incredulous that a french pilot on similar type could ignore his grim replay.

begs another question I have always wondered about:

How many working pilots actually read these reports in detail? Do they have the time? Or the interest? I imagine the answers to this are all over the map. It would seem, in the absence of any pertinent facts that, had FO studied the report, a lot of ppl would still be walking around the planet.

I know a certain pilot who blogs about piloting, and after a brief initial discussion on AF447, it was obvious that he had little interest in any of he nuts-and-bolts of that crash. Maybe complacency is part of this problem.