Air Asia Indonesia Lost Contact from Surabaya to Singapore

[SAMPUBLIUS]

FWIW re finding plane pieces

REPORTING FROM SINGAPORE [Times are in GMT+8, unless specified]
THE LATEST

10:53AM: Main wreckage of plane has been located, says Indonesia's search and rescue agency. Two large objects roughly 30 metres under the sea have been spotted near oil spills in the area near Pangkalan Bun.

[Leightman 957]

Not so huge

Hardly "main" debris, but makes a nice headline.

"The first object measured 9.4 meters by 4.8 meters by 0.4 meters (30 feet by 15 feet by 1.3 feet), while the second is 7.2 meters by 0.5 meters (24 feet by 1.6 feet), he said.

https://ca.news.yahoo.com/indonesia-...--finance.html

[Suastiastu]

bean counting

"over the years, beancounters et al. have sold to a wide audience that with today's technologically advanced aircraft, all you need at the pointy end is a couple of guys pushing buttons"


Not sure that this is a purely Asian or African idea. What Asia has is a very rapid expansion in aviation, so modern techniques are more prevalent. Air Asia has flown more than 220 million PAX and not lost one before. The way to determine if the bean counters are right is to look at the stats.

[Richard C]

""The most probable weather phenomenon is that icing caused the plane engines to be damaged," said the report by Indonesia's Meteorology, Climatology and Geophysics Agency (BMKG)."


Engine icing doesn't explain why the aircraft made no radio calls and why it travelled only 10km from a height of 36000 ft.

[ipsatex]

Erroneous overspeed warning, pilot induced climb, stall ....?

[Richard C]

"Erroneous overspeed warning, pilot induced climb, stall ....? ":

Yes, instrumentation icing does explain the observed facts a lot better.

But the last word, of course, will be from the air safety investigators, not meteorologists.

[catterwell]

About 10 km horizontal from 36,000 feet implies a descent angle of about 45 degrees. If wind accounted for some of this angle, that's quite a fall.

[Ranger One]

Airbubba, that's interesting.

Hard factual information will mostly have to wait for wreckage and especially FDR/CVR recovery of course, and much speculation before then is bootless and to me somewhat distasteful when done in public - but I've been keeping my eyes open for a proper formal met. aftercast; that should be available *now*.

What, exactly, were the conditions at the precise time and place they lost contact...

[Ollie Onion]

So they are flying along, encounter some pretty bad weather and request deviations to avoid. Pitots ice up and give erroneous indications leading to the PF inducing a 1.6g pull up resulting in a 10,000 ft/min climb and speed quickly reducing down to below stall speed. Aircraft ends up with 16 degree pitch up / 40 degree angle of attach / 60kt groundspeed and 11,000 ft / minute descent.

Total confusion on the flight deck as when the G/S drops below 60 kts the aural stall warnings stop as the angle of attack information is unreliable below this speed leading to 'reversed' indications i.e. push nose down and speed increases and 'STALL STALL' warning starts, pull back and reduce power and 'STALL STALL' warning stops.

Aircraft impacts the ocean with very little forward speed, a high rate of descent and a very high pitch.

No mayday call due to the very busy confused cockpit workload, not much left on the surface as the aircraft impacted in one piece at slow speed.

Oh oops, I have summarised the Air France 447 crash. I hope this is not the case, it would be a real shame for those lessons to have not been learned.

[oldchina]

Leightman

"The first object measured 9.4 meters by 4.8 meters by 0.4 meters (30 feet by 15 feet by 1.3 feet), while the second is 7.2 meters by 0.5 meters (24 feet by 1.6 feet), he said".

Those objects are pretty large by A320 standards. Both are bigger than the vertical stabiliser (approx. 5.9m).

[mikedreamer787]

Erroneous overspeed warning, pilot induced climb, stall ....?

Or EXPED button pushed above F250 in concert with TAI non-activation/failure?

Or Erroneous Alpha Prot activation (AB AD 2014-0266-E)?

Point is there's no use speculating any of this until at least the preliminary investigation has been completed.

[Nemrytter]

To add to the weather discussion, this article from the Malaysian Star tabloid:
...
The BMKG report, written in Indonesian, is here:
http://data.bmkg.go.id/share/Gambar_...TEOROLOGIS.pdf

Most of their "analysis" seems to have been taken directly from the website of an American University, much of the rest is from forecasts that, as it turned out, weren't particularly good.

[bud leon]

FLEXPWR, I don't doubt your observations. I'm very selective about which airlines I travel on in Asia. I don't doubt that there are many risks to quality in many parts of the world right now. What bothers me is that there is no reliable properly analysed evidence of cause in this incident but people have already arrived at a conclusion which clearly reinforces racial and cultural biases. Even referring to the region as the "Far East" sends a culturally biased message.

There is no doubt safety standards in Asia in many industries fall behind the west. That is a recognised development issue. There has to be some recognition that these are developing economies and standards also are developing. There is also no doubt that western safety standards are under increasing pressure. Whether there is a significant regional difference in aviation safety requires more than anecdotal evidence. This region, and aviation generally, are in a period of significant flux.

The statistical reality is that revenue passenger kilometres are increasing almost exponentially at over 5.4 trillion kilometres per year (doubled in ten years) and a lot of that increase is in Asia. Yet global airline crashes continue to fall.

Anecdotally there is equally sufficient information to suggest lapse standards in other countries… a quick look at this forum reveals pilots accomplishing hands free nose first landings into the runway, taxiing a plane to the gate on smoking rims, undershooting runways by 500 metres, landing at the wrong airport, landing on taxi-ways, stalling airbuses, the list could go on. I can't help think there are some cognitive biases at work here. Maybe there is a difference in standards, maybe the difference isn't as big as people imagine.

[silverstrata]

Midland 63:

What always surprises me reading these threads is the amount of disagreement among the pro's about topics which I would have thought were quite basic such as stall recovery.

Most of these guys commenting are wannabee's not pros, and you cannot take C152 experience and apply it to jets. Having said that, there are some pros out there who could do with a 20-hour refresher in a glider or puddle-jumper, because they have forgotten basic stick-and-rudder skills. (Because they are actively discouraged in some airlines - an old debate that has been aired many times here.)

Another problem is that the extremes of the flight envelope are often not explored in the sim, because you are not supposed to be at those extremes. So it would come as a surprise to many, if you did enter those forbidden areas.

An example of this, that few have explored in the sim, is a stall recovery at very low speeds and high power settings, which creates a thrust induced pitch-up (which is why you are supposed to reduce power in the stall). Reducing thrust in the stall is not a puddle-jumper technique, but is a must on jets with under-slung engines.

You will see from this example that even though the captain applied full stick forward very quickly, the pitch rose up to 44 degrees. (This is a real flight, with pax on board.)





There was probably a big 'thinks bubble' on the flightdeck, because the aircraft 'should not be doing that'. But it will, and it is a corner of the flight envelope that is rarely explored in training. So I will throw this out there to the pros - how many of you have actually practiced this scenario in the sim? Anyone? Would Air France have taught this in the sim? Or was it all dual autopilot all the way stuff?

The only thing that stopped this aircraft doing a low-level back-flip, was the wing dropping - thus reducing the vertical component of the thrust and allowing the nose to drop. Then, the captain was back in 'normal territory', and was able to recover very professionally in the normal manner.

[bud leon]

"Even referring to the region as the "Far East" sends a culturally biased message".

What the fook are you talking about? From where I live it's always been the Far East. I must go check my school atlas."

Exactly. From where you live. From the centre of the 21st century world point of view it's you who lives in the "Far West", actually. It's a 12th century term that evokes the exotic and culturally separate.

[Metro man]

If an A320 pilot really wants to he can simply switch off flight control computers until the aircraft goes into DIRECT LAW. In this case he would lose all protections.

Why is beyond me as there no advantage in being able to over stress the airframe.

No single computer failure will down grade the control laws it has to be multiple, and often a simple reset will restore normality.

There is a control mode which recognises an upset and will allow manoeuvres necessary to regain control which would normally be prevented.

[mary meagher]

Silverstrata, the very very scary example you have posted of a stall experienced on a real flight with pax on board, is impressive and how. Am I reading it correctly? is it actually rather low in altitude? and was the first response of the pilot to shut down the stall warning noise?
The stick shaker seems a bit late to arrive to get their attention....

This printout of all these happenings should be enough to wake up any airman who flies expecting the computers to do his job. I wonder if the passengers noted anything amiss? and if they were on approach, did ATC have any comments? can we read the report anywhere, please?

[mseyfang]

Most of these guys commenting...

This is a great post with an eye-popping set of graphs, but the bean counters will win every time on issues like this, sad to say. Training costs money and unless there is a strong financial or regulatory incentive to shore up training in areas like this, it just won't happen. The pressure on management is accountability to shareholders, not accountability to the traveling public or the pride that should come from running as responsible and safe operation as one can. So the MBAs in the Executive Offices run their cost-benefit analyses on this kind of stuff and decide it isn't worth the impact to the bottom line. Pilots are not an asset, they are a cost to be mitigated with things like P2F.

[BillS]

Can we read the report

http://www.aaib.gov.uk/cms_resources...OF%2006-09.pdf

[one dot right]

Could somebody please explain why airbus
can't fit their aircraft with pitot static probes with
enough 'oomph' so that they don't ice up in a CB when
you really need them to be working?