AirAsia flight missing

[AVION1]

Well - it hasn't happened to Malaysia. It was an Indonesia Air Asia flight from Surabaya, Indonesia, to Singapore. Saying it happened to Malaysia is like saying it happened to Germany if a Brussels Airlines flight between Belgium and Africa is involved in an incident.

Air Asia is from Taiwan. Their headquarters are located at Tainan Airfield. One of our customers, by the way.

[Evan]

353kts groundspeed?

ITCZ... CB's... climbing... decaying speeds...

Alternate Law?

Please not again.

[Peter Kesternich]

Air Asia is from Taiwan. Their headquarters are located at Tainan Airfield. (...)

Air Asia is from Malaysia (Edit: with subsidiaries in several other countries, none of which is Taiwan):

http://en.wikipedia.org/wiki/AirAsia

http://www.airasia.com/ot/en/about-us/corporate-profile.page

AVION1, please do your homework before posting something here

[Gabriel]

Air Asia is from Malaysia:

http://en.wikipedia.org/wiki/AirAsia

http://www.airasia.com/ot/en/about-us/corporate-profile.page

AVION1, please do your homework before posting something here

I think that there is more than one Air Asia, that it's a multinational holding of companies. A group of airlines belonging to the same group.

A LAN flight isn't automatically Chilean, since you have LAN Chile, LAN Argentina, LAN Peru...

EDIT: It's in your very link:

The AirAsia Group services the most extensive network across Asia & Australia which comprises of the following airline affiliates:

AirAsia Berhad (Malaysia) - Airline code: AK
[...]

AirAsia Indonesia - Airline code: QZ
Established on December 8, 2004, through a joint venture between AirAsia International Ltd. and PT. Awair International, with hubs in Jakarta, Bandung, Bali, Surabaya and Medan.

Thai AirAsia - Airline code: FD
[...]

Philippines’ AirAsia - Airline code: PQ
[...]

AirAsia India - Airline code: I5
[...]

AirAsia Zest - Airline code: Z2
[...]

AirAsia X - Airline code: D7
[...]

Thai AirAsia X - Airline code: XJ
[...]

Indonesia AirAsia X - Airline code: XT
[...]

This was AirAsia Indonesia Flight QZ8501

[Peter Kesternich]

I think that there is more than one Air Asia, that it's a multinational holding of companies. A group of airlines belonging to the same group. (...)

That's what I wanted to point out, and there is no Air Asia subsidiary in Taiwan (yet).

[Gabriel]

353kts groundspeed?

ITCZ... CB's... climbing... decaying speeds...

Alternate Law?

Please not again.

I hope we don't have another Air France. Won't we ever learn from other's death?

That said, I have hopes that this is not the case.

The ground speed was 353 @ FL363.

That gives us an EAS (CAS corrected for compressibility) of 191 kts and M 0.62. I don't think that an A320 will stall at that speed (Well, a plane can be stalled at any speed. A pull up to climb or to keep the nose from falling in a turn will increase the load factor and hence the AoA and the stall speed).

Also we would need the A320 downgrading from normal law (again), since in normal law the plane will simply not stall.

I would like to see a blip after the one in your picture. There should be (an)other one(s) during the fall, unless the transponder stopped transmitting (Disconnected? Airplane torn apart in flight?)

(By the way, yesterday I've watched the Mayday episode of West Caribbean. In that case it was an MD-80 with mechanical controls, no switch from one law to another that might confuse the unaware pilot, two big obvious yokes that move together, it was the ITCZ but there was no ice buildup, the airspeed was ok, the FO recognized the stall condition, and yet they still managed to stall it all the way from 33000 ft to the ground)

[andyb99]

Air Asia is from Malaysia

so i was right!!

it has happened to malaysia again!

[3WE]

...mechanical controls, no switch from one law to another...two big obvious yokes that move together...yet they still managed to stall it all the way from 33000 ft to the ground)

May need a dissertation on the question: Can you really un-stall a fully stalled airliner?

They really are not designed to do stalls, they are almost never deliberately stalled...I mean are they really recoverable?

The MD-80 is one of those T-tail, deep-stall specials- but who says that any other airliner is any better. (And, maybe they are recoverable on your AeroEngineer formulae sheet- but maybe it's not so easy for the Mark IV low-silica carbon autopilots?)

And of course, don't forget the pyramid of importance...You should ALMOST never ever see a stall warning- airspeed (and AOA and hard pull ups) should be critically managed to avoid a stall warning during normal operations. For the actual stall itself, you should really just about truly never ever reach a stall with an airliner...And if you DO reach a stall, you should pretty much always immediately recover...(don't bust me on my use of absolute terms)

Could it be that if you get it fully stalled, it's real hard to get back out?

[Evan]

I would like to see a blip after the one in your picture. There should be (an)other one(s) during the fall, unless the transponder stopped transmitting (Disconnected? Airplane torn apart in flight?)

That screen shot was swiped from AvHerald. ADS-B was lost one minute after radio contact was lost, but this shows 363 and climbing. They requested FL380. This was a nearly full flight about halfway to its destination (no idea of course on fuel order or payload or GTOW at this point) requesting the approx. service ceiling for the A320. And this ITCZ vulnerability should be well-known by now. Ask 3WE what to do if you lose airspeeds while climbing.

There was also a report in the LA TImes that the request for 380 was denied due to traffic conflict.

[Evan]

And since AF447 I think airlines are pretty tight-lipped about ACARS data, but there is a distinct signature for that scenario...

[Evan]

Hereis the load sheet: http://www.dephub.go.id/public/0507_001%20AWQ8501.pdf

They departed 10,000 under MTOW.

Pax manifest here: http://www.dephub.go.id/public/0506_...%20AWQ8501.pdf

The death toll could have been much higher. This is max-cattle configuration.

[3WE]

Ask 3WE what to do if you lose airspeeds while climbing.

The broadly applicable answer that works on essentially all aircraft:

1) Maintain a familiar attitude and power setting that gives you a healthy airspeed (see Footnote 1)
2) Check (and turn on) pitot heat.
3) One dude fly the plane. Another dude troubleshoots.

(Footnote 1: A familiar attitude and power setting from any of your previous 500 flights in type will probably work well- though one might avoid the higher performance ones)

The Evan Answer:

Refer to the correct checklist (Edit: See Footnote 2) for the particular situation for your particular aircraft. Do not confuse it with any number of other checklists for other situations or aircraft types- including the checklist of what to do if you have passed V1 but the plane won't rotate.

Edit: Flip the guarded switch marked "No airspeed indication so show me what you do know instead of a bunch of noisy, distracting warnings".

(Footnote 2: The wording "Checklist in the POH, flight manual or QRH" was specifically avoided so that memory checklist items would be included)

[Evan]

The Evan Answer:

Refer to the correct checklist for the particular situation for your particular aircraft. Do not confuse it with any number of other checklists for other situations or aircraft types- including the checklist of what to do if you have passed V1 but the plane won't rotate.

You forgot memory items. You could be a line pilot.

PS: let's drop it for now...

[AVION1]

I think that there is more than one Air Asia, that it's a multinational holding of companies. A group of airlines belonging to the same group.

A LAN flight isn't automatically Chilean, since you have LAN Chile, LAN Argentina, LAN Peru...

EDIT: It's in your very link:



This was AirAsia Indonesia Flight QZ8501

Thanks, Gabriel.

[Gabriel]

May need a dissertation on the question: Can you really un-stall a fully stalled airliner?

They really are not designed to do stalls, they are almost never deliberately stalled...I mean are they really recoverable?

Yes. Certification requirements mandates that they must be fully recoverable from a full stall (or, else, that it must be "stall-resistant"). And, believe it or not, this condition must be demonstrated in test flights, not just theoretically derived.

Now, one thing is a "full stall" and another is an "obscene stall where the AoA reached 40°, 30 seconds after the plane has stalled and the pilots kept pulling up".

So, if the question is "can an airliner recover from an obscene stall". The answers are "I don't know" and "depends on the type".

For example, in the Air France case, when the pilot applied a few seconds of continuous full nose-down stick, the AoA diminished. It diminished enough, in fact, that pitot tubes, now a bit more aligned with the airflow, started to produce a more sound airspeed indication, which in turn cancelled the "no stall warning because the airspeed is too low for the AoA indication to be reliable", which in turn re-activated the stall warning that had been silent for the last bunch of seconds. I have no reason to believe that the AoA would have not just kept going down had the pilots kept the nose-down input. It would have taken some time and quite a bit of altitude though.

Now, an MD-80 maybe is not recoverable from an obscene stall. Not so much (or only) because of the T-tail, but because of the aerodynamically powered elevator. But it can recover from a full stall. As a proof:

The MD-80 has a sequence of stall protection measures.
- Autoslat: IF the plane was in a configuration with slats 1 (mid position, sealed) and the plane approaches the stall AoA, the plane will automatically extend the slats to the full, gaped setting. (Why it doesn't work in clean config? Because the system relayed in AoA only, and at high altitude this AoA can happen at a Mach number beyond the slat limit. And because the plane in clean config gives clear warnings in the way of buffet of an impending stall, even before the stick shaker).
- Stickshaker: This stall warning activates with some margin before the "full stall" condition.
- Stall warning: Will sound an aural message saying "Stall, stall!!!". This happens at the citical AoA (where the lift will not increase anymore by increasing the AoA).
- Stick pusher: If the AoA reaches a certain value past the previous level, the plane will push the stick and pitch down by itself (although the push force is one that can be overridden by the pilot). And it works. The stick pusher recovers the plane from the full stall beyond the critical AoA. This feature works only with the slats extended, because the stall AoA is quite higher with the slats extended and there is more risk of a deep stall (a treat of some T-tail designs, where the elevator becomes ineffective because it's under the turbulent "shadow" of the wing). It was considered that with the clean wing the stall warning and actual stall, as well as the natural pitch-down response of the plane to a stall with no pilot intervention, was enough protection to avoid a deep stall.

Of course, unless you are in an Airbus in normal law, nothing, in any plane, will prevent that the pilot keeps pulling up upon a stall (and against all natural and artificial push-down forces) only worsening the situation.

So the first question to answer your question is:
Will the pilot even attempt to recover a full stall before (or even after) it becomes an obscene stall?