Life raft retrieval by Singapore ship
 

Raft would appear to be partially inflated as it comes aboard?

No, groundspeed and track.

Yes.

No idea.

Is that not an escape slide? (Which granted may be used as a flotation device).

I realize that I increased the amount of the updraft it was for simplicity of calculation. I still think that the more likely cause of the upset would be the coincidence of a severe updraft and a jump in OAT that would confuse the ADIRUs. If that was linked to sudden accumulation of clear icing from liquid water droplets in the updraft that could block pitot/static ports, then things could get very confusing for both the automatics and the flight crew.

Experts on the Airbus AIDRU algorithms should be able to give an idea on how they could react to:
1. Sudden OAT increase in cruise at FL320
2. Sudden loss of reliable pitot/static information (possibly associated with (1).

The response of the FMC to the AIDRUs could be added to a sudden updraft with a VS of let's say 5,000fpm (to use a value in line with your CAPE values). If the FMC initiated a 'protection' pitch up at the same time as the ambient air was lifting the aircraft at 5000fpm it might explain the apparent unlikely climb rates.

Or maybe it has, assuming the passenger quota for SUB-SIN was correlated to all the other flights through the area and had something to do with potential safe AC density and separation in an habitually weather threatened airspace.

The machine has radar. It has multiple sensors and computers. When it sees that it is about to enter a turbulent zone as detected by radar, or indeed enters one, why can't it go into a 'Cautionary' mode where it will be anticipating conditions (large buffets, icing) and react accordingly, instead of not anticipating anything, flying along as if it is blind when it is in fact not, and blithely and stupidly sounding stall warnings when the airspeed drops by a ridiculous amount in an incredible time? If you're going to automate things, then automate them. Don't even display data that fails creditibility tests - it just confuses the pilots. Just pause the game, maintain thrust and attitude and display possible viable alternative data such as INS derived airspeed and AOA* to the pilots, remain engaged using such data but give the crew full unrestricted control if that data indicates flight outside its parameters. Do this until such time that conditions are such that credible data is again calculable, verified with the INS data, and only then display that data to the crew.

Its no use having the million dollar computer display rubbish to you.


*as the INS can describe a FPV then all the factors contributing to that vector can be calculated, even airspeed
(Please do educate me here if I'm incorrect, I'm just a pilot not an expert)

"Is that not an escape slide?" - indeed, but when detached becomes a 'raft' as per drills.

"not that it has any relevance to why the accident happened. Or maybe it has.." - no - totally itrrelevant. This is a route licensing issue and has zero to do with this accident as far as I can see - a true 'red herring' which could even be 'political' trouble-making by another carrier.

Air Scotia : Yes. Normal SSR codes.

DrPhillipa :Absolutely not. Reason(s) for the Minister agitation is elsewhere, and he is not finished as I heard.

ASEAN Open Skies
 

I understand very little about the ASEAN Open Skies policy, implementation of which is supposed to be complete by year end. But it does seem to be creating some friction between Indonesia and Singapore. That the Minister repeatedly failed to enforce an agreement between the two countries probably puts him in political hot water. Hence this unexpected CYA blame-shifting.

Asean open skies on track - The Nation

http://thejakartaglobe.beritasatu.co...sean-open-sky/

Ice?
 

I admit to reading only 66% of this thread so perhaps I might have missed something. Apologies if this is the case.

It is well known that the CFM56 fan is neither capable nor certified to tolerate bird strikes of a size such as occured in the case of US Airways Flight 1549. A little research reveals that earlier CFM56 fan sets suffered from resonance and high-cycle fatigue. And in addition, rain/hail ingestion has also given rise to several incidents with this engine.

Perhaps what is generally less well known is that CFM56 fan blades have been observed to suffer significant damage in the event of ice accretion. When this occurs, high levels of N1 engine tracked order vibration are likely to be observed, along with audible changes in engine 'tone'. The consequences of prolonged engine operation in this condition merit little discussion.

The following report therefore, although not conclusive, contains some degree of credibility:

AirAsia Flight 8501 Crash Possibly Caused by Icing, Indonesian Report Says - WSJ

Are A320 and B737 pilots routinely trained in ice shedding manouvres, and what is the policy for avoidance of potential ice accretion?

By way of explanation, my personal backgound is in aircraft and engine prognostic health monitoring, including engine bird strike detection and fan blade damage detection.

A thought. Now that accellerometers are so tiny, would it not be possible to mount sets of them at each extremity of the aircraft (nose , tail, wingtips) and then calculate a graphic representation of the aircraft's movements in space? Could be presented to the crew as a 3rd person view perhaps?

Thanks IcePack. It was a simple question - can I set the a/c up at turbulence penetration speed/mach, power and attitude and the a/c will then maintain power and attitude and ignore any other sensor inputs?
I get the impression the answer is 'no', because the various protection systems will kick in.

A question for those who know A 320 cabin sidewall materials.
There was an image earlier in this thread of a damaged sidewall, including the window surround, that was recovered at sea. The sidewall was neatly cut across the top, is though it had been sheared.
Is there anything other than high speed aerodynamic stresses that can shear a composite structure so cleanly?
It seemed to me that this bit of debris was pretty strong evidence that the aircraft had broken up in flight. Is this a mistaken belief?
Certainly the absence of any cockpit communications during a long fall from 30 odd thousand feet is more consistent with a catastrophe than an icing/loss of control scenario.
After all, they were in ongoing ATC communication, unlike AF447.

etudiant.

As I answered to the original poster of that picture, we need to see the adjacent structure to make any claims of any sorts.

This type of damage can occur in many ways. One of the many ways may be that when the plane hit the ocean the forces made the bottom half snap cleanly from the wall structure but the upper part may have been stuck by, well, let's say, an overhead cabin and thus the crumbled upper part. This is just one of MANY explanations for this. Please remember that.

Etudiant

anything 'other' than high speed aerodynamic stresses that could do that,?

Whatever you mean by high speed aerodynamic stresses... lots of things could. A kniife like object striking it maybe...

Water is hard when struck at any speed.
Depending on how an object is supported acceleration or deceleration alone can achieve surprising things. Aerodynamic s doesn't have to come into it, high speed or not
so proof of nothing yet IMHO

NB. Aerodynamic Forces create stresses (and strains) on objects... per se there
is no such thing as an aerodynamic stress, other than maybe between molecules
of air.

The debris found shortly after the AF447 crash showed similar characteristics, and that was high velocity impact with the ocean. The cruise-level destruction of MH17 resulted in much smaller pieces (apart from engines) and fragmented bodies.

Slats11, your economic model is a little off. It should be Revenue - (Fixed Costs + Product Costs) = Profit. The biggest fixed cost savings which LCC find is in operating from cheaper airfields. They will only operate from expensive airfields when loading is always high (e. g. Hong Kong). Through clever hedging they might save on fuel as well but that can be a double edged sword. Whilst staff costs are cheaper in Asia than in Europe, there is no difference here between legacy and LCC carriers. Both pay peanuts for ground staff and cabin crew but both have to recruit internationally for the flight deck and maintenance. The real savings are in product costs. LCC try to achieve higher turn around times and higher efficiency by removing services which are not required in order to perform the contract of moving the customer from A to B. The inference that LCC are compromising safety is not accurate because if they were, their insurance premiums would move in tandem, killing their profit. Allianz actuaries will be sratching their heads trying to figure out why Malaysian* airlines are now such a big risk. 3 crashes yes, but no obvious link.

*Air Asia Indonesia is controlled by its parent, Air Asia notwithstanding that for political/legal reasons an Indonesian investor appears to own 51%.

Thank you for the considered replies.
I spoke of high speed aerodynamic because in my limited experience, composites rarely snap cleanly as they did here, they usually have bits sticking above the line of separation, unless the break is very forceful and sudden. That plus the abrupt silence of the crew together are pretty significant, imho.

@Machinbird

Here is a KML file which expands on my post 1197.
Plug it into Google Earth and you will find the FR24 data plotted, showing the actual coordinates along with the debris locations etc.



https://www.dropbox.com/s/8j2tl52m5d...08501.kmz?dl=0

Part ID
 

Clips on this piece have been noted previously. What is top and what is bottom?
http://news.bbcimg.co.uk/media/image...8_80044577.jpg
I answered my own question: clips are at the panel top as suggested by A320 photos showing a radius on the panel concavity below the window. Panel bottom torn, top undamaged.

'Crashed AirAsia jet's pilots did not get weather report' according to Jakarta Post
 

'Crashed AirAsia jet's pilots did not get weather report' - The Economic Times

Sorry if already posted. If true, I'm stunned :eek:

The only window I've seen is a plastic panel which is undamaged at one end and torn at the other. The wind probably tore it from its fixings. Would all passengers please replace their tin foil hats.

Given that the fixings in the bottom of the photo have hooks pointing up, I'd imagine that's the top. We can all rest easy knowing if we get bored on our next flight we know how to annoy the cabin crew by dismantling the interior of the aircraft.

'Crashed AirAsia jet's pilots did not get weather report' according to Jakarta Post 'Crashed AirAsia jet's pilots did not get weather report' - The Economic Times

Sorry if already posted. If true, I'm stunned :eek:




Seen that there were other flights shortly ahead of him, behind him and to either side of him, it would be surprising if any weather reports would have changed a thing for the pilot of 8501.

ettore, I am going to post what I already posted on the 31st December, as I am led to believe, if we apply "normal" European decision making as regards go/no-go, whether to penetrate weather, how much separation to allow, there would be NO air travel in this part of the world.

I therefore humbly submit, that the failure (if there was one ) to get a "weather report" is neither here nor there in the grand scheme of things. Throw your hands up in horror if you wish, but, I am led to believe that, operating in that part of the world, is based very much on firstly going, and sussing it out the best you can once underway.

Standing by for corroboration/shooting down as required, but that is how I have been told it is. My (prev) post below.


I have not had the "pleasure" of flying in that part of the world, however, a couple of very experienced colleagues that did, for some time, intimated to me that if you did not accept to routinely fly through weather that you assuredly would avoid in Europe, you wouldn't operate any flights.

I doubt (knowing the individuals & their experience) if this was too much of an exaggeration, I believe it is quite probably the day to day reality of ops in that part of the world.

@etudiant

May be, may be not.

But - and again if this is true - it would be quite dearly telling about poor airmanship, safety culture and it would draw hefty liability consequences.

@captplaystation

May be. But - again, if this is true - it would certainly draw hefty liability consequences.

RE: "pilots did not get weather report"

That article strikes me as pure hyperbole. Does this newspaper expect that Captain Iriyanto was supposed to sit on the runway for an hour and a half waiting for a weather report?

This Captain was local to the area, he knew what the weather was like (all he had to do was look up as he walked to the plane.) There were a half a dozen other planes out in that weather, he could have gotten pireps anytime he was curious. Weather reports can only give generalized reports for an area, they can't pinpoint individual cells anyway. That's what the planes' weather radar is for.

Much ado about nothing.

Thanks ekw. I doubt there is any significant connection for Allianz to find between this, MH370 and MH17. They appear to be 3 very different incidents.

In some ways I find this the most disconcerting due to possible underlying factors.

I had simplified it a bit. Less popular airports, less popular timeslots, pre-packed food (for sale), reduced baggage etc are among the many ways LCC reduce costs. My point is LCC pay much the same for planes, interest rates, and fuel. So there are only so many places they can reduce costs. And so everything that is discretionary is reviewed to minimise costs.

Not so sure about that. The fact is that airline travel is very safe so it is difficult to see any differences that may exist. So people have to make subjective decisions due to insufficient objective data. As others have commented however, most people can't do this and price is paramount.

We are in the midst of widespread and probably unprecedented changes between society and technology. Never before have people been so divorced from the technology they use. This is a general issue that is changing all society. Aviation is but one symptom of this.

I think these changes are a risk for all. Air France is not a LCC. But I do believe LCC are probably more vulnerable to these changes.

Captainplaystation, exactly.

If you fly in or near the the ITCZ for long enough, sooner or later you are going to end up, where you shouldn't, or don't want to be. There can be many reasons for this.

The important point being, give yourself plenty of margin for this eventuality.

Culture

Properly trained crews anywhere can be as good or as bad as anywhere else. However if they are allowed to pressurized by corporate greed and face punishment by a culture of fear and intimidation, that is a recipe for disaster. This is especially so for inexperienced pilots who maybe allow themselves to be so pressured influencing incorrect decisions. This is where, a proper regulator (or lack of) that ensures this doesn't occur is the real problem, as I see it.

Properly trained crews anywhere can be as good or as bad as anywhere else. However if they are allowed to pressurized by corporate greed and face punishment by a culture of fear and intimidation, that is a recipe for disaster. This is especially so for inexperienced pilots who maybe allow themselves to be so pressured influencing incorrect decisions. This is where, a proper regulator that ensures this doesn't occur is the real problem, as I see it.




Here we have a very senior captain on a routine flight, which was also routine for the many other airplanes in the same sky at the same time.
It is difficult to extrapolate this accident into an issue centering on 'corporate greed' or ' a culture of fear and intimidation'.
That just seems a cop out to me when we have a very specific accident to evaluate.

Icing
 

Ice shedding can be done on the ground or engine anti ice used in the air to get with the ignition turned on for maximum protection in the vicinity of weather.

Even if both engines flamed out due to there would be the means of communicating with the ground and plenty of time. Therefore engine icing is improbable and this incident was sudden and catastrophic.

Agreed.

I was generalizing with the culture thing. We will never eliminate human error, no matter what the culture.

To all who looks at the debris photos:

When you see many adjacent part in context, then you can often tell what may or may not have happened. The photo of the relatively intact airplane window panel can not be taken out of context. It there are more debris found you can start making deductions.

If several pieces of debris turn up rather undamaged like on the photo, a scenario where the plane hits the water with minor or no external damage MAY be what we're looking at. Reference the popular AF447.

If several pieces of debris turn up that are small and shattered you are more likely to have an in-flight break-up like Air India 182 (also a water event).

Please remember that even in the cases of Lockerbie and MH17 (debris on ground, not water) there are several pieces that are somewhat large-ish and undamaged so there are huge pitfalls in trying to guess from only one photo of debris.

So, can we move on from that window panel now?

Please continue to post photos of debris as they turn up though, I follow this thread more closely than any other news outlet.

Yes, that's a fair point alright!

what i want to hear on the cvr
 

1. fasten seat belts cockpit and cabin including FAS

2. engine ignition on, engine anti ice on


3. rough air penetration speed

4. adjust tilt and gain on wx radar

5 direction of clearer air if things get bad

1 - for pax, a "ping" on the recording, I am sure it was done, if it was rough, quite possibly much earlier, if it was indeed ever switched off / for crew . . if some real nasties were anticipated, normally a conversation on the inter phone, or, in extremis (never been there personally ) "CC be seated immediately " or suchlike on the PA.

2 - not neccesarily a call out, with TAT colder than -40c, TAI not required on a B737, don't know for A320 but, same engines, so would imagine similar, ignition is normally "Auto" so crew action only required in severe turbulence

3 - if it is rough, agreed "may" be some verbal discussion, but most companies PF may make adjustments to speed without verbal confirmation to the other crew member.

4 - Good luck with that one. . . .

5 - there may be some discussion about which way to turn, and, normally, a request to ATC to do so, but. . .it isn't a bloody hollywood movie FFS, so, lack of "verbal annunciation", should not be interpreted as "asleep/not paying attention/not on the case". . . . Are you a current/rated/practicing/member of crew/Jet Transport ? if not, well. . .you are, a bit of a "clutter" on a semi-serious discussion. . . .as bloody usual on pprune :ugh:

Experts....

How susceptible are ADIRUs to extreme turbulence? Specifically, the attitude section.

I seem to recall an incident with one of our aircraft (Boeing) which lost two of the three IRUs due to severe turbulence (perhaps about 10 years ago). I can't recall, however, if the IRUs were switched to ATT mode to help recover basic attitude displays.

Do ADIRUs have more than the basic 3 laser gyro and accelerometer pairs?
Do A320s automatically switch to an attitude display if navigation mode is lost? (plus manual backup). Of course, ATT mode is mode is useless if you can't achieve level flight for a certain period of time.

Note: I've even seen faulty attitude displays on ISFDs (with solid state accelerometers) after a manually generated upset. A reset was required.

There's a lot of talk about using pitch/power when air data is lost, but if attitude was lost, too....

Where are the CVR/DFDRs located on the A320?

Are they in a section of the fuselage which is surrounded by metal on all sides which may attenuate the ultrasonic signals? Could they be in an air pocket and not submerged in water?

Other than rough weather, I'm trying to speculate why no signals have yet been detected.

SOP Monkey

In the experience that I quoted previously the OAT at FL410 went from ISA+2C to ISA+29C in the space of 5 seconds. However I would speculate that this would be less critical for an A320 at FL320, although it would put a cold aircraft surface back into the temperature region for super-cooled water droplets.

Since I don't fly the A320, any Airbus drivers got any suggestions on how an A320 would handle a sudden temp change of that magnitude at FL320?

"Other than rough weather, I'm trying to speculate why no signals have yet been detected."

There have been reports about mud and silt on the sea floor being a problem with recovering likely debris, so attenuation of the signal might be a factor. It can only ping if it's not buried in mud.