From the CAPE values (around 2000 J/kg) indicated by the model analysis I calculated MAXIMUM updraft velocities of around 55 knots. In reality, rain-loading of the updraft reduces actual velolcities by maybe 30-40%, but let's allow for some stronger outliers too. I still can't see 100 knots being possible, but that's a moot point at this stage.

I bet they were already climbing before the FL340 clearance was issued. The fact that ATC never got a response tells me QZ8501 never heard the clearance and they were already out of control.

What time was the FL363 screenshot taken?

Here are two examples of the timeline as reported by two sources:

There has been no mention so far, that I recall having been through this whole thing, of Air Asia HQ, or Maintrol, or whatever receiving any ECAM Mx fault messages, correct? I assume their ACARS was working that day.

I have read most posts here, and have formed the following take-home messages:

1 Air travel is demonstrably much safer than at any previous time - several recent high profile crashes not withstanding.

2. Air travel is becoming cheaper in absolute (not just relative terms). Its not just a LCC thing. I flew Qantas Sydney - LAX return for $1515 in 1990. I can get much the same fare on Qantas cheaper than this in 2015. Given fuel and labor costs are a large proportion of overheads, it is incredible that costs have decreased in absolute terms over a 25 year period.

3. The emergence of LCC have increased this trend, But it was happening anyway.

4. Commercial aviation is highly competitive, and many airlines fail. Airlines have little discretion over three large overheads - cost of fuel, cost of planes, and cost of borrowing to buy planes (interest rates). There will be some economies of scale of course, but other than this airlines presumably pay much the same for these three things. So when looking to cut costs, airlines can only look to costs of staff, training costs, and maintenance (off-shoring this as much as possible). Cadet ships and P2F reflect the fact that this is where airlines can cut costs.

5. In an increasingly high tech world, people have less understanding of the equipment they use. Whatever they use is increasingly a "black box" - whatever happens inside is a complete mystery. If something breaks, it increasingly needs to be fixed by a professional or else replaced. People have less ability to understand how things work (and they are persuaded they have less need to understand anyway as they are so reliable and nothing goes wrong).

6. Aviation is part of society and is not immune to trends in broader society. Airmanship and a thorough understanding of the aircraft has been gradually replaced by automation and SOPs and ECAM etc. At the same time, it is cheaper for the airline to rely on automation and SOPs, and not to teach airmanship and sound manual flying skills. So all the drivers here are aligned in the same direction.

7. Managers in all walks of life love SOPs as they create a level playing field in their eyes. A SOP can be read by a non-operational manager. SOPs eliminate "judgement call" as a defence for a decision made - non-operationsal managers always hate these as they are unable to judge a judgement call. But they can judge adherence to a SOP. So SOPs serve to dichotomise an individuals performance into either "right" and "wrong" - in a way that is accessible to a non-operational manager.

8. Due to reduced cost, worldwide capacity has increased dramatically. When you need to dramatically increase supply, quality can suffer. People who would not have made the cut a few decades ago now get through (this isn't just an aviation thing either). And everyone wants to believe that quality pilots don't really matter much anymore. The airlines want to believe it to reduce costs. The airplane manufacturers peddle this line knowing it is what the airlines want to hear.

9. On top of all this, some people here suggest a problem with Asian cultures and over-reliance on automation. They point to the presumed cause for this crash, or Asiana 214 at SFO (and overlook the western crews of AF447 or QF1 at Bangkok). I have spent a fair bit of time in Asia, and enjoy the culture. Maybe there is a case that the deferential culture at times allows small problems to develop into big problems. Maybe. But I suspect the real issue has less to do with the culture per se, and more to do with:
a) this is where growth has been most dramatic (and hence quality control is likely to be most problematic)
b) developing countries mean developing standards (as mentioned by others)
c) they have to deliver the product at a lower price consistent with the lower cost of living in this region. They pay the same for fuel and planes, so guess where the savings are achieved.

And I suspect that worldwide aviation has much bigger problems to address than different cultures in different areas. Because our similarities are greater than our differences.


Its all a bit grim. Particularly as bean-counters will keep pointing to number 1 (increased safety overall) and state there is no problem.

Slats

That about says it all. Fate is of our own creation and she is now very much the hunter.

Accident statistics prove only that HAL mostly has the situation under control but when he has an off day, the operators are less and less capable of doing anything about it.

glendalegoon, try using a decent sized screen & not an i-phone



slats11 , good (but depressing to realise ) summary :ok:

bunk ex:
Air Asia A320s as far as I know are not ACARS equipped

Slats

Regarding barometric pressure changes in a strong up drought. I am more concerned about the possible temperature change if entering a strong updraft. Apart from the up drought itself upsetting the aircraft, that temperature rise will play havoc if you are struggling along with 1.3 G protection at say ISA. If the ambient temperature is suddenly ISA +10c (not unheard of) or ISA +05c.

The above example is just one reason to consider an even lower altitude, if "caught out". Sure you're in for a rough ride but the chances of staying in control and not departing are so much greater.

FR24 has ADS-B information for QZ8501
https://twitter.com/flightradar24/st...840256/photo/1

From this we see that the FR24 last known position was seen at 23:10:57 at 3.996 s 110.232 e. This is much closer to the area where the big pieces are resting (the FR24 LNP is about 21 miles west of the debris location)

I tried to calculate speed for the last two position reports and came up with a speed of about 20 kts. This calculation may not be accurate as it may be affected by the timing of the ADS-B transmission (the sample period is only 36 seconds.) But it could actually represent the forward speed of QZ8501 in its last seconds.

If I back up and calculate the average speed for the last 100 seconds of FR24s' data I find an average GS of 329 Kts.

(3.996 s 110.232 e to 4.083 s 110.335e = 54,897ft)
(23:10:57 to 23:12:37 = 100 seconds)

54897 / 100 * 60 * 60/ 6000 = 329 K


The FR24 information provides a last known location that is much more in accord with the debris fields being reported.

(We never have been told where the earlier Indonesian supplied last known positions came from - primary radar or ATC radar.)

Can you tell an Airbus autopilot just to maintain attitude and power, effectively taking the height and speed locks out?

Flight and duty times in Indonesia are 14 hours duty time (with up to 3 hours extension) and 9 hours flight time. Abit more than in most countries, but you'll find that flying four sectors a day is the norm these days (even at Lion apparently, since the Bali Kuta beach landing).

Weather mystery queries continue
 

06:12 QZ8501 requests left deviation from airway. Deviation approved.
Pilot then requests climb from FL320 to FL380
ATC asks pilot to standby, due to nearby traffic and to coordinate with next air traffic control sector (Singapore)
Who was the nearby traffic and what exactly was their seperation at 06:12? Was it flight UAE-409, AIr Asia flight M635 etc and how come none have reported unusual effects due to weather?

Could it be that a weather 'bomb' is so confined to such a very small local area that craft in the region experience little or no effects from this hazard?

hail shaft can be very isolated..

nickp. That is what you get on FBW aircraft when you take the Auto Pilot out. However the system is complex and to understand it you need to take a type rating. (basically Auto pilot is guidance only)

Times Strait reports:
 

“.......Five major parts of the Airbus A320-200 have now been found off the island of Borneo. But rough weather last week hampered the search, a huge operation assisted by several countries including the United States and Russia.

During a momentary respite from bad weather, a team of divers went down to the biggest part of the wreckage Sunday morning and recovered one body, while another three were found floating in the sea, bringing the total number recovered to 34.

The divers "managed to go down but the visibility at the sea bottom was zero, it was dark and the seabed was muddy, with currents of three to five knots," search and rescue agency chief Bambang Soelistyo told reporters.

He said the fifth major part of the plane, located early Sunday, measured about 10 metres by one metre.

The search, focused on a site southwest of the Borneo town of Pangkalan Bun, has also been extended east because parts of the plane may have been swept by currents, Soelistyo said.....”

Another article on Times Strait today reports:

"JAKARTA - The chief of Indonesia's search and rescue agency Basarnas expressed optimism on Sunday that the black box of AirAsia Indonesia flight QZ8501 was located "not far" from five large objects the search operation had spotted in the Java Sea.

"The black box should not be far from the five significant objects we found," Mr Fransiskus Bambang Soelistyo told a media briefing at the agency's headquarters in Jakarta late on Sunday.
Officials had believed they were close to a major breakthrough after pinpointing five large objects on the sea floor thought to be parts of the Airbus A320-200 jet this weekend. But Mr Bambang Soelistyo noted the ongoing difficulty facing the multinational recovery operation: "Our challeng is mud. Lots of mud at the sea bottom.”.....Up to now, he said, no vessels had detected any signal beamed from the black boxes, or flight recorders. He said five vessels with the ability to locate black boxes will be assigned on Monday. The weather also remains a problem, he said. "Several (divers) tried to dive but had to return. Safety is also important for rescuers," he told reporters...."

The other traffic in the area probably just did a better job deviating around the weather.


http://i2.photobucket.com/albums/y17...es-graphic.jpg

I'm just trying to check if I have missed something in the last week
The update above by jcjeant is clear but it sure doesn't seem to match even 50% of the post so far on this thread.

I'm all for some speculation but there seems to be too many twists and turns of sub level (given that. given that, given that) this probably happened conclusions.

It seems that the visible wreckage and bodies to date only confirm a water impact and nothing else. Still TBD, possible inflight breakup, twists and turns, or flat impact

Nothing on the sea floor as yet confirms that the main wreckage has been found, let alone understood regarding how the plane entered the water.

Maybe it's just me and I missed something said earlier but how does the day of flight permissions have any bearing on this accident cause?

Basarnas: Debris show plane body broken - Malaysiakini

One interesting line in that news item is "Indonesian transport minister threatens to sack those who cleared QZ8501 for take off when AirAsia was not permitted to fly on Sundays" - not that it has any relevance to why the accident happened.

Also interesting is that no pings received from the black boxes - I wonder why?

Flightradar's ADS-B for the end of the flight.

https://twitter.com/flightradar24/st...840256/photo/1

Someone has commented on the 7001 squawk, which puzzled me when I saw the FR24 playback. The AirAsia flight following just behind squawked 7002, I seem to remember.

Are those squawk numbers allowed for civilian flights in that airspace?

I would suggest, from a quick look last valid position was 23:12:01 - it seems to slow then stop after that? As does the data rate (from every 3s to a big gap). Quick calc by me makes it 494K?

Are the 3rd/4th columns from the right TAS & Hdg? Track? 2nd V/S? Last column?