warning not for the squeamish

They don't need "qualifications for judging such things". If the passengers recovered:
* show signs of drowning with water in the lungs etc. Then the impact was not sufficiently hard to kill the passengers.
* Show signs of explosive decompression with ruptured ear drums and associated signs of barotrauma it is possible the aircraft decompressed at high altitude
* have compression fractures and broken lower limbs etc. and no signs of drowning Then the impact was probably severe and the aircraft landed flat onto the surface of the water.
* have seatbelt bruising and associated inuries perhaps some with signs of submarining under the seatbelt, then the aircraft had significant forward velocity when it hit the surface.

etc etc. There are more but I don't think I should belabor the point.

Associate these simple observations with any deformation of the seats and airframe and you do not need a DFDR to show what the final seconds were.

A number of posts earlier in this discussion have mentioned that an angle of attack instrument would help the pilots make a better assessment of a possible stall condition. I noted with interest that in the AF447 final report that is readily available on the web, in section 4.2.2 it says, "Information on angle of attack is not directly accessible to pilots", and a couple of lines later, "it is essential in order to ensure flight safety to reduce the angle of attack when a stall is imminent. Only a direct readout of the angle of attack could enable crews to rapidly identify the aerodynamic situation of the aeroplane and take the actions that may be required". That seems a clear enough recommendation concerning the A330.

The A330 aircraft type involved in the AF447 accident did have, as standard, angle of attack sensors installed, but may have become blocked in the weather conditions prevailing at the time of that accident.

Does any A320 pilot here know if the situation is similar on the A320 i.e. that AoA sensors are installed, and the data available to the flight control system but not as a direct readout that the pilots have access to? Or was the fitting of AoA sensors not part of the design of the A320?

I'm sure that any ship operating in the area has their passive gear listening 24/7. Dragging the fish can be done in most weather conditions, sometimes it needs to come in for feeding and a nap. Depending on your gear it may be safer and more efficient to bring said fish aboard while daylight is on your side.

No divers were involved in the retrieval of AF447 and its black boxes. Can the same technology not be employed in the Java Sea?

Having read the entire AF447 thread, if memory serves, AoA gauge was an option on the 330, one that AF didn't buy.

Organfreak


Perhaps the BEA was making the point that while the AOA is read and recorded on the aircrafts records... there is/was no display for a pilot to use in flight.
(AF did not fit the BUSS display. Apparently this becomes less useful above FL 25.0.)

other photos ...
 

http://www.malaysiakini.com/news/285810

very small photos, but a couple I have not seen on here thus far. Plus, local TV reporting says one body found strapped in recovered seat is from the cockpit ... so what wreckage have they found ?

and very clear new video:

http://www.kinitv.com/video/14462O8

edut:

TWA sold several of its 747s to the Shaw of Iran circa 1974.

One of them exploded on approach to Madrid. It was determined that it was lightening that hit the wingtip and went into one of fuel tanks through the tip vent.

After that TWA, and I presume other airlines, installed lightening suppressors in all those wing tip vents.

Technically it is possible. But it is much cheaper and efficient to send down human divers. Especially in conditions like that, with strong currents and bad visibility. Relatively shallow depth with plenty of daylight available on the bottom makes it easier for divers.

WSJ article with some updates: Bodies found in wreckage, impact injuries found, pathologist(s) requested analysis of lung contents, autopsies being done on foreigners.


AirAsia Flight 8501: Official Says Black Boxes May Not Be in Tail Section - WSJ
Excerpt:
Search teams on Friday also recovered the bodies of two victims still in their airplane seats from the tail section, bringing the total number of recovered bodies to 48. The two bodies were the only ones to be found so far in the wreckage.

Autopsies carried out on several victims from AirAsia Flight 8501 have revealed impact injuries such as broken legs, but no burns, early clues that may help investigators figure out what happened in the crash.

Air-safety experts said that means there likely wasn’t any fire or explosion that tore through the plane on its way down, and the jet probably hit the water at a shallow angle.

“It was most likely a flat impact,” according to Michael Barr, a senior accident-investigations instructor at the University of Southern California. Based on four decades of experience, Mr. Barr said, “the flatter the impact, the less trauma damage to the body.”

The impact of a vertical or near-vertical descent, according to Mr. Barr and other experts, probably would result in the plane breaking into smaller pieces than the wreckage suspected of being on the bottom. The broken legs of victims are more consistent with a scenario of a plane pancaking into the water, Mr. Barr said, which likely would have resulted in the fuselage or seat assemblies buckling or breaking apart. That, in turn, could transfer huge stresses to the limbs of passengers strapped in their seats.

Lung samples from the first few autopsies have been sent to an Indonesian laboratory for signs of seawater and plankton following a request from pathologists, said Budiyono, the commander of East Java’s disaster-victims identification service, who goes by only one name.

“If there’s sea water or plankton in their lungs, then we can say that they were still alive when the plane crashed into the sea,” he said.
Pathologists have been able to speed up their investigation after more bodies have been recovered during the past few days.

They are focusing on trying to conduct post mortems on foreigners who don’t have the same cultural sensitivities to the procedures as many Indonesians, Mr. Budiyono said. Indonesian authorities have decided to conduct autopsies on all foreigners recovered from the crash, unless families expressly reject the procedures.

Several regulations were added in the 1970s and on regarding lightning protection (at least one in direct response to the 707 accident barit1 listed). In the 1980s, flight critical avionics were pretty new and novel (FBW and FADEC) - on the 747-400 the FAA issued a special condition for lightning (and HIRF) protection of the FADEC systems (later codified into FAR 25.1316). I presume the A320 had similar JAA requirements for the FADEC and FBW systems.


To the best of my knowledge, it's been several decades since a commercial jetliner has been lost due to lightning. While weather may well have been a factor in the loss of Air Asia, it's unlikely to be directly lightning related.

Lightning
 

I don't believe that lightning can be dismissed as a possible factor in this accident. As a glider pilot, I am well aware of the inherent danger of flying into or near thunderstorms, and the following report from the AAIB on the loss of a glider is of interest, particularly, as recommendations are made in the final paragraph regarding the degree of lightning strike protection in commercial aircraft.
See http://www.aaib.gov.uk/cms_resources...pdf_500699.pdf

sopwithnz posted a link of a remarkable short video today (Saturday Jan. 10) 00:48 GMT in (permalink) http://www.pprune.org/rumours-news/5...ml#post8818649.

The Youtube link for that short but remarkable video is http://youtu.be/-ATg1APGVYM .
What you see is divers entering the opening of the RH aft full-size door (normally used as a service door). This part of the structure appears to be laying more or less on its left side.
Clues (at t = 6s) for which door opening it is are the rain gutter above the aft top corner of the door cut-out, as well as the dark external paint on which the last letter of the large “AirAsia” fin and tailcone decoration can just be seen.
At t = 27 s the camera is panning around the door post (or possibly the open door) with what seems to be the typical handgrip that you grab to not lose your footing when handling the door (which rests parallel to the fuselage in the open position).

What this area may look like on an A320 in maintenance:
http://photos1.blogger.com/img/26/35...D2D6993-01.jpg looking across and aft, galley removed
http://photos1.blogger.com/img/26/35...D2D6832-01.jpg looking aft, galley installed.

There have been a number of speculations about breakup of the fuselage at the point of impact with the sea surface, or whether the aircraft would have remained largely intact if it had not broken up prior to hitting the sea. It is possible to do some ball park calculations that help understand the impact conditions. If the aircraft was descending at 5000 feet per minute, and impacted the sea in a near level attitude, and if the floor area containing the seat mountings in the fuselage area came to a halt uniformly in a distance of 2.5 metres vertically then one can work out the deceleration. Using very basic mechanics the deceleration is the square of the speed divided by twice the deceleration distance. Converting the initial vertical speed to metres per second gives 25m/s, and this leads to a deceleration of a little over 12G. It is quite possible that the deceleration happened in rather less than 2.5 metres and if it was 1 metre this gives deceleration loads of 30G. That is unlikely to be survivable. In addition this implies that the forces on component parts during impact are over ten times the normal forces under 1G loading. Hence deformation and failure of any parts of the structure are highly likely.

Given this kind of consideration it is not surprising that the most likely outcome is to find separated sections of the aircraft. The analysis of the debris field would of course need to include some estimates of the effect of sea currents both during the descent from the surface as well as post accident strong currents in the area. It is positive news today that the tail section has now been lifted from the sea onto a ship.

Interesting Video!
It almost looks as if the entire lower and left half of the fuselage are missing/open, whereas the right side looks rather intact and the intact/remaining on the upper/right half part appears to stretch pretty far forward.
Somewhat weird wreckage pattern. The apparent missing of the lower half (if I saw it correctly) really strikes me as strange in a pancake type of arrival.

So now we are back in the 'can-we-find-the-ULB-before-the-cheap-batteries-run-down' game again. All this extra work being proposed for streaming DFDR data is because the existing DFDRs are poorly designed their location systems are only useful in an inland lake or river (and perhaps not even then).

In the 'old days' before solid state memory there were all sorts of survivability issues; but with fast solid state memory with significant capacity this is not a problem. The real problem is the use of batteries that just do not have the power driving ULBs that are unsuitable for crashes in the ocean. Obviously, the beancounters at airlines are not interested, but it is time for an international mandate to have ULBs that actually work.

I would suggest that the ULBs requirements are:
Detection Range At least 25 nautical miles in open ocean
Battery Life At least 6 months, possibly by reducing number of pulses and using smart transponder that does not go into regular short location signals until it receives a search request sonar signal
Encoded Location Signals The signals from the ULBs should be encoded with airframe ID, their position (last GPS position of the aircraft) and their depth in the water.

These requirements appear to be asking too much and all that is being offered is a slightly longer life battery.

Comparing the photo of the fin/rudder and the video taken in the rear door area suggests that at least 2 large sections have been found. Concerning the video, it does rather look as if part of the lower shell may be missing in the area under the main cabin, although the diver could be standing on it, the cabin floor being absent. Interesting to note that the overhead bins stop just ahead of a large hole in the skin, which appears not to be the door. Isn't that where a lavatory would normally be?

Current Range seems ~2.5NM, 30days.

So you asking for something that lasts 6times as long (maybe a bit less due being "smart"), and is 1000x as powerful? So needing say battery capacity 2000x current kit?

That is a "major" change, and bearing in mind the 'g' / depth / other strict requirements I suspect unrealistic. NB just stuffing big batteries into autonomous kit is hardly flavour of the month right now (787 LHR fire).

Bear in mind these things do not directly save any lives, and assuming they find the Air Asia DFDR / CVR soon, just save some search effort.

Henra

FWIW: Add to the musings a report yesterday or the day before that authorities believed then that the aircraft entered the water in a left hand roll, based on what they had inspected at that point.

Also a report a couple of days back that bodies found to that point represented passengers seated in various different parts of the cabin.

Slightly bigger photo on this site plus a bit more info.


AirAsia Flight 8501: Tail Recovered - WSJ


The compression damage just forward of the tail section suggests an initial impact on the port side.


With regard to injury damage correlated to G, the US Navy aircraft accident manual gives the following:

Injury sustained Deceleration
Nose - fracture 30G
Vertebral body - compression 20-30G
Fracture dislocation of C1 on C2 20-40G
Mandible - fracture 40G
Maxilla - fracture 50G
Aorta - intimal tear 50G
Aorta – transection 80-100G
Pelvis – fracture 100-200G
Vertebral body – transection 200-300G
Total body fragmentation >350G

Source: How crashed planes like AirAsia flight QZ8501 are salvaged | News.com.au

Not necessarily a 1000 times more powerful - choice of a different frequency could easily increase the range. Apparently the frequency was chosen as it was not a 'natural' frequency. Encoding would provide the same 'not natural' effect so the frequency could be one that has longer range in water.

The rate of transmission could be as low as once every 3 minutes instead of (I believe) around once every half second.

BEA also put forward a request for this type of improvement (from the BEA report on search operations for AFR 447 http://www.bea.aero/fr/enquetes/vol....11.2012.en.pdf ):

Air Asia Indonesia Lost Contact from Surabaya to Singapore
 

Tail section being raised.

How can they ever say they 'hope' to find the black boxes in the tail. Of course they're not in the tail. They would've detected the pings if they were.

On the pings from Channel News Asia:

FRUSTRATING TWIST

But the search took a frustrating twist when authorities realised the pings were likely coming from elsewhere than the tail, and the boxes appeared to be buried deep into the sea floor.

"Last night, our divers had opened the door of the tail cabin, searched around but found nothing," Supriyadi told AFP on Friday morning. "But the boat above detected faint ping sounds believed to be from the black boxes about one mile (1.6km ) southeast of the tail ... and covered in mud."

Supriyadi said the divers, from an elite Marines unit, returned on Saturday morning to the area believed to be where the pings were emanating from.

"They are searching within a radius of 500m from where the pings are emitted. The challenge is that these sounds are very faint. If a ship passes by, the sounds will be drowned out. So we really need calm waters," he said. "So far, our divers still have not been able to determine the coordinates of the black box."

Does it appear we have VS and a bit of upper fuselage?
No HSs/tail cone and so on?

As far as I can make out, the DFDR and CVR should be in the section in the video on YouTube and roughly where the divers feet are, which is not good news.

Here are some bigger Pictures of the Tail Section for You all to watch.
Note that all the Lower Part of the Airframe is missing:

http://abload.de/thumb/1628x1471vau1y.jpg

http://abload.de/thumb/2628x24716juog.jpg

http://abload.de/thumb/2628x2471219u9b.jpg

IAN W:

The bean counters have never been interested in such things.

The technology already exists and is being used. My cousin said he routinely sends devices 6000 meters down in oceans and they will answer him back only after he transmits to them. The batteries last over a year.

Video of recovered tail
 

Here is a video of the recovered tail section, presumably taken from the same helicopter as the photo in BJ-ENG's post. Good view at the 20-30 secs position.

https://www.youtube.com/watch?v=LG8i...ature=youtu.be

The size of the fuselage wall section is remarkably large (several windows) suggesting that the CVR and FDR were originally in that part of the plane. But it has broken up pretty badly IMHO from the point of view of finding the recorders.

PS: I think the fuselage has split along the bottom, and in the picture it is lying upside down on the ship's deck.

Be really interested to see close up the leading edge of the vertical stab

DFDR weighs about 20 lb. It would sink faster than tail and it should not be pushed by the current .
I think it could be in the opposite of where the tail was found ie northwest

That is one of the more ridiculous statements I have read on this thread but typical of a naysayer. Here we are, almost half way through the ping life, and there is no clue where these things are. They didn't even find some of the big bits until a couple of days ago. This jet pranged in a populous part of the world in 100ft of water, but because of the archaic gear on board (as with every other modern aircraft), the event is still a mystery. This is beyond a joke.

Collectively the industry has been working for years to revise the ULB standard.

It's not as "easy" as just switching the frequency as there are many tradeoffs involved (power vs. range vs. frequency vs. rate of transmission vs. size vs. weight vs. cost vs. crash survivability, etc.)

SAE did a ton of analysis and in 2012 produced a new LF-ULB standard (AS6254), specifying 8.8 kHz for 30 days, with an assumed detection range of 5.8nm in normal conditions.

This standard has already been incorporated into FAA TSO C200, and accepted by ICAO in 2012 (Annex 6 Amendment 36) which mandates LF-ULB on all aircraft with MTOW > 27,000 kg starting from January, 2018.

ICAO mandate aside, in practice we will basically have two types of ULBs:

- Standard frequency 37.5 kHz ULB capable of operations for 90-days

- Low-frequency 8.8 kHz ULB capable of operations for 30-days

For shallow water recovery not far from shore (like this AirAsia crash), LF-ULB doesn't matter as much and 37.5 kHz will continue to be used for many years.

For deep sea recovery, aside from MH370 consider that in the past 20 years there have only been 6 airline accidents with wreckage submerged in 1000m depth or deeper. Of those, 100% of the FDRs and CVRs were successfully recovered using existing technology.

The FAA and EASA will likely require LF-ULB only for transoceanic flights (> 180nm from shore) starting in 2018 or 2019.

But it was not 'the industry' that paid those extended recovery costs. 'The industry' was getting a free ride on the taxpayers of the location of the crash. In the same way that MH370 searches are being largely funded by Australian taxpayers.

Perhaps if 'the industry' or rather the airline and the manufacturer were billed for the costs of the recovery process, we would see a significant jump in the eagerness to get DFDR/CVR that could be rapidly recovered, as the cost to the Airline would be unsupportable. Attempts to insure against these recovery costs would result in the insurers demanding a better DFDR/CVR location system - or no insurance.

Recovered tail plus ...
 

plumbrob, henra, smott999 - tail recovery

First impression is that we see part of the aft top fuselage panels down to the underside of the left and right exit doors. With 5 windows on each side. And 6 frames clearly identifiable, and upto 5 stringers under the windows. I have not seen floorbeams yet.
All lying upside down on the weather deck of the Crest Onyx of course.

The vertical tail looks suprisingly good. But a small part of the lower part of the rudder is torn away. Speculation - that might have happened when the tail with THS and APU were torn away.

On one of the recent pictures is a part that looks like the front end of the fuselage to wing fairing. Which looked pretty good. No information if it was recovered floating or underwater. First impression is floated.

And you would be wrong on both counts.

While governments initially fund searches, in many cases (such as MH370) extended operating costs will be charged back to the airlines, which in turn pay the charges from their insurance policy.

In the case of MH370, Malaysia Airlines has a $2.25 billion per crash liability policy with no caps for Search and Rescue. The Australian government has already reached out to Malaysia to seek reimbursement from this insurance fund.

In the case of AF447, Air France and Airbus directly funded the search for the blackboxes.

More relevant to this case (in Indonesia), Adam Air directly paid for the search and recovery the Adam Air 574 black boxes.

No doubt similarly AirAsia (and their insurer) must absorb / reimburse a large portion of the SAR costs.

For more "routine" recovery operations, governments typically do not charge back the airlines, but that's because the airlines and flying public already pay billions in taxes each and every year for routine government services (which include SAR).

An excellent summation of the problem Ian. Of course, the present arangement has evolved from International treaties that should probably be re-examined in light of present technology.

Hmmmm....Peekay4 refutes Ian's assertion, with the qualifier, I suppose when the price gets to be real money, the chargebacks occur. What happens when the uncapped Search and Rescue costs bankrupt the insurer? Do the bankruptcies flow down the chain of re-insurance?


As an interim measure, why don't we instead clone some of this dfdr/cvr data and store it in additional locations on the aircraft in hardened memory modules. Locations like the wing tips and vertical stabilizer tips would be good choices. If imbeded into lightweight cushioning/floatable material, possibly also equiped with a water activated ELT & pinger, we have upped our chances for swiftly locating crash scenes and recovering the data. Design the component to have a high probability of being released under crash loads and the problem will be significantly mitigated, without having to re-negotiate the international agreements.

Meanwhile, lets hope the pingers are still bolted onto the black boxes. It would be very discouraging to recover a solitary pinger with no reward.

Shape of tail debris
 

Fewer comments since tail raising on shape of debris than on search methods and batteries. More than anything the tail section looks like a paper bag popped open except for the fuselage face that impacted the surface which fragmented. Pics/vids in situ showed the section retaining some shape which has largely been lost in raising and under gravity out of the water. If other fueselage sections split similarly the large skin sections would have acted like sails in the current while sinking. I've looked at a lot of accident debris (though many fewer with water impact) and such large contiguous skin sections of 8501 laid open seem rare. Question whether the next section forward is found to be similar. Whether a flat belly flop, or a nose-first air compression of aft fueselage, or any other impact attitude still very unclear.

BJ-ENG's post on G's vs human body damage applied to public pics so far suggest lower end of G scale.

Thanks for this Smott999 - tail damage
 

Cannot remember ever seeing damage like this. Perhaps someone has an example.

More common to see a separated "complete tail-section", or separated "vertical tail plus rudder".

Pure speculation. To imagine getting something like this, using an aircraft model, you would grab the "front fuselage and wing" with your left hand and hold it tight. Then with the other hand grab the horizontal stabilizer and rotate it till "it" breaks off.
This would also give an idea about why, more forward, the top fuselage panel was torn from the stiffer lower section. The remaining top part then rotates with the heavy tail down and the panels flatten when hitting the water. The remaing top part has more 'lift' than the lower section. So could move further.
Wonder where that lower section is. The why and how of this scenario ... has to wait for far more data and photos.

As far as I know the span of the horizontal stabilizer is 12.45 m and the distance from the top of the fuselage to the top of the vertical tail is about 5.87 m. If someone wants to make a 'torsion' calculation.