Anyone remember MI 185 and how the NTSC and NTSB (on behalf of Boeing) came to different conclusions on that one?

I am fluent in Indonesian; I’ve seen and heard the original quote by the Barsanas chief.
Regrettably, there was no error in translation. He really is saying that, in his “analysis,” the plane “exploded” on impact with the water, and that the air pressure differential consequent to the impact caused the passengers’ bodies to be expelled from the plane.

Keep in mind that Soelistyo is not an accident investigator; he’s an ex-military general who now leads the mostly civilian search and rescue agency.
While Indonesia does have some good technical experts, Soelistyo is not one of them and there is unfortunately not a culture of message discipline here.
Expect more premature and cringe-worthy conclusions to be aired: The first was the meteorological agency; the second (and very much under-reported) was last Thursday’s announcement by Santoso Sayogo, the NTSC (Indonesia’s NTSB) lead investigator, that the ping locators will no longer needed, since the tail had been found — even though, at that point, no pings had been detected from the tail; and now Soelistyo’s gaffe.

The best reading of Soelistyo’s remarks is as a “just-so” story to explain the absence of victims’ bodies from the fuselage, which the Indonesian public widely expected to be still strapped into their seats. In remarks as recently as Sunday, Soelistyo repeatedly stressed that the recovery mission will prioritize recovery of victims’ bodies over that of the black boxes. Now he has to explain why the divers under his command surfaced with boxes and not bodies.

The NTSC’s Sayogo should be lauded for quickly rejecting Soelistyo’s speculation: “There is no data to support that kind of theory,” he said a few hours ago. You need some courage to do that to a general here — and one on whom your investigation depends for operational and logistical support.

Yep, they're doing autopsies on all the foreigners, on presumption of family permission. Autopsies on the Indonesians only if the family permit. There was a church group onboard, so the ME might get higher consent rates than with more Muslims on board.

No professional investigator or materials engineer would be confused by scrapes or scratches from the recovery effort.

And post-mortems are performed for each and every body recovered so far. This was already explained before.

It's worth to re-quote bud leon:

"If you are just going to take barely-informed pot shots from the sidelines, it says more about you than it does about them."

Answer to mm43 - FDR and CVR coordinates
 

3°37'20.7"S 109°42'43"E --------- acc.to A0283’s plot, new object, so probable CVR,
3°37'21.13"S 109°42'42.45"E -----acc.to A0283’s plot, coordinates published for FDR,

offical, previously stated FDR coordinates were:

3°37'21"S109°42'42"E

but they are 21.7 meters apart.

offical,previously stated distance estimate 20m,

A0283 addition - Taking mm43's 21.7 meters. And the offical statement that the
FDR was stuck under 'the' wing. CVR appears to be too. If we take a wingspan value
of 35.80 meters ... An 'intact' wing could easily cover both locations.

Picture from Antara News:

http://img.antaranews.com/new/2015/0...115-pras-2.jpg

This appears to be an L-3 Aviation FA2100 Solid-State FDR.

I believe the engineer's body has been recovered (based on the obituary postings on FB from those who knew him). And engineers who accompany flights which is common in Indonesia normally sit in the cabin (something to do with cockpit authority gradient) and usually at the back or emergency exit row if not taken by a passenger who has paid more for the extra legroom.

@TWheels

Your sure of this are you.....less to do with SOP??

Debris recovery, media, 'explosion', 3km
 

peekay: "No professional investigator or materials engineer would be confused by scrapes or scratches from the recovery effort."

I don't know if I would go that far, but the recovery crew needs to be cut some slack. My first reaction on the winch-aboard' was 'they're squashing it'. But the "tail" was more like a paper bag ripped open than an airplane, with one heavy, rigid piece (v stab) still attached. The 3D structural strength of the tail portion below water was insufficient out of water. The entire section would have required a redundant structure built around it to maintain the section's shape. The subsurface work would have to be performed over days with little visibility in what amounts to a cyclone of current flow. And there are more pieces waiting to be recovered.

News media so far is reinforcing the observation that there is nothing it can be told that it cannot screw up, misinterpret, take to the most illogical extreme, ignore language differences, fail to ask for clarification, or let die as inaccurate. We can be sure that every blind alley and patently false notion will be given equal, or sometimes even more earnest, concerned emphasis than clear statements of fact. We can further anticipate the errors, misinterpretations etc etc etc will be repeated and repeated and repeated by photogenic but otherwise clueless talking heads, referencing one another and welcoming false prophets and experts chosen for their dialectic positions until falsehoods approach the refined virtual news reality which is where news viewers are expected to function and like it. The statement of 'explosion by air pressure' is interesting, but has already been grabbed by media and morphed into Frankenstein. Pprune is a place supposedly sheltered from such media fallout but is not immune to it.

3km between FDR/CVR and tail section is a significant distance on smooth paving, and farther on water. We are lacking the early stages of a debris field map, overlays of current, and updates. Hopefully they will begin appearing.

I think 3km is a lot I'm sure a 6kt current can't move 20kilos of metal that's sat in the sand

@Livesinafield: "I think 3km is a lot I'm sure a 6kt current can't move 20kilos of metal that's sat in the sand"

At 6kt that distance represents about 20 minutes - if one of two pieces sinks straight away after surface impact and disruption, and the other floats for 20 minutes before sinking carried by a current flowing at that speed, that does not seem particularly unrealistic?

I would not bet on that. Diver and sailor here - the amount of force 6 knots of current exerts on a large and light metal object is immense.

No Boofhead, I do not jest. They were crap.
I cut my ITCZ teeth on B732's in West Africa in the early 80's. My prevailing memory of those old radars was dodgy unreliable displays, lots of twiddly knobs to play with, and the definite impressioin that half the time they were serving you BS. Maybe because my crusty old Captains weren't 'adept' enough at twiddling the knobs. Or maybe because it was a black art that required a lot of concentration to work right - the kind of time you don't always have when racing around at 500mph in a storm filled sky.

Indeed a pair of my colleagues were almost killed by one of those cranky boxes. They made the mistake of interpreting a gap in the display as a hole. It was in fact a 'Super Cell', blanked out by radar attenuation. The aircraft was almost a write-off. The damage was impressive.

C Band Radar requires larger antennae, and other heavier equipment (so I'm told) so other solutions would be developed by necessity. The new radars do not require anything like the artistry of the old systems to give you useful info. When you say 'pilots don't know how to read/operate their radar' and instead recommend a return to those prehistoric glow tubes of old - you are being a bit of a luddite, nothing more. There is every likelihood such a system would create more problems than solutions. So I'll keep my modern, stabilised, bright, colour contoured, computer enhanced, map overlaid MODERN Wx radar thanks. If you want you can always switch off the automatics and play away to your hearts content with the raw data, ground clutter, noise, and all the other rubbish.

The bottom line is - the new stuff shows the weather very well in my experience. You use it to avoid - not penetrate CB's. Doing otherwise is the only possible explanation I can come up with for your love of those old boxes.
Good luck.

All or most of the pax will have died from the same cause, so a few autopsies should be enough.

Are you sure the super-cell would not be black on a new radar too? Very early on with the monochrome digital radar we had back in the day, we learne the black blobs in the middle of the green returns were the worst areas to fly, not holes in the storms. The physics of extreme rain absorbing the radio waves has not changed.

Correct.
Also with modern radar, any black area surrounded by Red is to be acoided at all times as this is probably an area where the data is invalid due to much precipitation...

On some models, this is supposed to be depected by magenta, not on the radars I operate though.

Large ships and some boats will fit S band radar that can burn through heavy rain, but the antennas would never fit anything but an AWACS airplane.

The airline I worked for in Indonesia welcome the engineer to sit in the jumpseat, but if they weren't required to be there to troubleshoot a problem, then they usually chose to sit in the cabin unless, of course, when we were full and they had no choice. On such occasions, I got the impression they felt uneasy being in the cockpit, which I suspect is due to the authority gradient.

3km, explosive
 

Tail section carried 3km is believable only if the tail was down current from the FDR. When we see current direction overlaid on a map of FDR and tail section locations it will be clear enough. Or more puzzling if the tail was cross stream or upstream.

I don't know anyone who does not with hindsight regret their choice of words from time to time, especially when in front of a crowd or on camera. I don't yet see anything contradictory in the 'explosive..air pressure' statement'. Sounds may be mis-interpreted, so must be considered separately. But a high volume, high velocity intrusion of seawater midpoint into a mostly horizontal fuselage could be expected to result in some cabin air overpressure. The paper bag analogy remains viable. Do recall also the fuselage frame pic of the skin neatly unzipped from the intact frame. The most likely cause of that is a sudden, very large, very uniform internal pressure. One must come up with an alternate cause for the unzipped skins to be able to disregard a fuselage overpressure. The video of the fuselage in situ which also shows virtually all cabin contents absent suggests a significant force having removed them.

And remember that these radars regardless of their age are showing the rain which is mainly in the cold downdrafts. Warm updrafts will show a lot weaker on the radar but the turbulence will be as bad as the rainy downdraft and sudden changes in OAT can confuse the ADIRUs.

Do any airliners fit stormscopes or equivalent technology? One of their selling points was that lightning was found in turbulent air, heavy rain or not. I liked the one I had way back when. Not as accurate as radar, but it worked.

Reading FDR
 

Numerous news reports about the recovery of QZ8501's flight data recorder say it might take up to a month to read the data. Can anyone tell me if this is true and why it takes so long, especially if the FDR is intact, as this one seems to be?

As a professional aviation investigator and materials engineer I concur with peekay4's comment.

Moreover, I think it is important to not overplay the significance of the airframe impact damage. Think about what happens when an aircraft impacts land rather than water. Events X, Y and Z occur at altitude, leading to aircraft loss with ground impact. There will often be massive deformation, tearing and even burning of the airframe as a result of the ground impact. For the most part there is not a lot of significance that can be attributed to the somewhat random large-scale airframe damage caused by ground impact, other than determining things such as approximate speed, attitude and angle at impact (I'm in no way saying that impact damage and ground witness marks are unimportant, just that for the most part these are a consequence of a chain of preceding events that are often more significant to the investigation). Despite extensive ground impact damage, the evidence of what occurred is still there to be found, and far more often than not the factors leading up to the accident will be determined by the investigation team.

It is not easy hauling damaged airframes out of water without causing additional deformation and damage. My point is that some salvage-induced damage is not likely to be a big deal w.r.t. determining what happened with this flight.

island airphoto,
I can remember being struck by lightning in a clear blue sky when flying out of Tel Aviv - no turbulence and not a cloud in the sky! Lightning in thunderstorm is not associated with turbulence in the same that way that water droplets are.

The old radars were monochrome. So how did you tell the difference between attenuation caused by a super cell and an actual gap? You couldn't. Well, maybe if you were highly skilled in the black arts you might be that kind of genius who just COULD tell the difference. Black holes didn't always appear neatly ensconced in the centre of green blobs. In the event I referred to the guys reported no green contour - just a nice clear (black) gap between the green blobs. A sucker hole.

With a modern contoured radar what would you expect to see in the same scenario?
A green contour, followed by a yellow contour, followed by a red contour, maybe some purple - then, what? A hole? Blackness?
Well it might depend on your radar set, but my suggestion is you don't go near RED or PURPLE, and try your best to avoid YELLOW and GREEN too.
That'll keep you safe.
No guesswork or black art required.

PS Radar attenuation is part and parcel of the system. If a sufficiently strong beam is emitted it could pass through all weather giving no returns. Not much good for WX spotting.
The signal needs to be of just the right strength to be partially reflected thus showing the WX. The snag is the weaker beam also suffers attenuation.

Stormscope
 

Island Airphoto:

Yes, I remember flying around with a Stormscope, they detect static electricity from moving air currents, not necessarily lightning, and so are pretty good at telling you where the rough air might be... especially at low level, but I would expect a Stormscope would be overworked in an area of multiple active CBs - just too many dots! They were mostly intended for light - non radar - aircraft. I never flew a heavy aircraft with one.

Any fuselage "overpressure" would be caused by the force of water entering the cabin, and nothing to do with air pressure. Air easily compresses, water does not.

Algol - we used to try and get a ground return on the far side of the storm to see if it was a hole or heavy rain and then tilt up to get an idea how hight the tops were. It was far from foolproof with the small antennas on a piston twin, sometimes you just had to keep away from all of it or heavy rain where you were would blind you to what was coming. I suspect that is still true - heavy enough precip where you are right now won't let you see very well if even worse is in front of you.

Has this been posted before? Video that shows a rear door on the tail: BBC News - Navy releases new underwater footage of AirAsia plane

http://i2.photobucket.com/albums/y17...1.jpg~original

Lessons from AF447
 

Surely the impact that occurred with AF447 would be a good model for an intact aircraft hitting the ocean at relative high vertical speed? I do not recall there being anything that might have been described as some kind of cabin over-pressure 'explosion' due to water ingress. It seems very unlikely that the aircraft would hit in a sufficiently flat attitude, that would avoid a structural break up at critical stress points - meaning there would be no intact pressure vessel to "over-pressure".

Impact comparison to AF447
 

Garage Years: Surely the impact that occurred with AF447 would be a good model for an intact aircraft hitting the ocean at relative high vertical speed?

The comparative issues of 8501 forward and vertical impact speeds are very much current conjecture. Despite the extreme depth of 447 wreckage, drift during descent still resulted in a debris field that was not gigantic. The degree of fragmentation of AF447 both by map and underwater photos compared to what little we know of 8501 debris at this early stage of recovery, and based on much conjecture, suggests relatively similar impacts might result in much different debris characteristics. The large area of 8501 tail section skin is about our only clue at present that suggests impact differences, but its large area is persuasive toward some causes.

AF447: Map of the debris field - Flight International

I am hoping that the black box manufacture and the Australian ATSB are helping the Indonesia Govt retrieve the data from the boxes & right now they are just behind the scene on the deck of the ship during the news photo ops.

Mr S...that’s what I am worried about too...Airbus will want to place the blame solely on the pilots and not on any potential recalls/redesign/liability claims/potential loss of orders.

Googled “australia ATSB Airasia 8501” and this came up:


"The Australian Transport Safety Bureau (ATSB) has agreed to an Indonesian request to provide a flight recorder specialist when needed."

BG47

Since it is Airbus, and in water, I am sure the French are there already.

The french are there alright
 

Airbus and the BEA are both heavily represented. Photos of their people near the wreckage are evident in the press. Let's hope someone will be looking very closely over their shoulders to make sure the full and complete data from both from the FDR the CVR (when it is recovered) is made known and public. Whatever the data/conversations tell us about pitot tubes, FBW, direct vs alternate laws, crew training, P2F, decision making, cockpit resource management, etc, etc.

Algol: I did not ask for the return to the older radars, what would be the point? You demonstrate that modern pilots would not be able to use it anyway.

If I am coming up on a large area of activity and need to find the best way through (and I don't have the luxury of a super-airliner like you obviously fly so cannot go over it) I could, using the old equipment, find the route I wanted. Since you don't know what I am talking about there is no point my explaining it to you as to how to go about this, but believe me it was possible.

Modern radar makes all those decisions for me and for a modern pilot that is fine and dandy. Quite often though, the modern radar is wrong.

I am sure that the Seattle branch of the agency have them permanently in their sights, so do not worry.

Can you amplify that remark, preferably with a technical reference? I find the physics, as worded, difficult to relate to.

Dr. Phillipa wrote:
Would you care to spell that out in so many words, Dr.? :*

After it sinks the current will move the wreckage until it becomes anchored to the sea bed e.g. it skidded along the bottom until rotated so the VS lodged into the sea bed.

I have one in a piston single, but it was next to useless *before* XM WX or ADS-B In's FIS-B. Now, I wouldn't pay to get it fixed or removed. Nothing replaces the Mk.1, Mod1 eyeball...