Thanks to Sardak for the Hudson plane photo - very helpful in clarifying how the HS sits inside & illustrates what some are saying about how the HS movement should be limited by the beam below.

Also, thanks to triumph61 for the photo collection - makes it much easier to visualise the overall situation when the images are all together in one place.

Here is a piece normaly located below Door 2L.
http://img5.fotos-hochladen.net/uplo...8zcfdyilaw.jpg
http://img5.fotos-hochladen.net/uplo...nr7xis8z69.jpg

on the right side this piece is located
http://img5.fotos-hochladen.net/uplo...pchiqd3voj.jpg
http://img5.fotos-hochladen.net/uplo...tfz43qak6g.jpg

HS pivot link
 

re excellent posts 2004/2026...port side top link fracture, stbd side bend and fracture. If the port hinge assy lost integrity first the HS would move violently down, but also rotate to the left, this could amputate the flight recorders. The slots whereby the HS is inserted would be unable to contain the released forces. The tailcone upper mount failures are different, but there appears little damage on the tailcone separation ring, which puzzles. It is possible the combined forces of a loose HV subsequently fracture the aft fuselage?

https://img-fotki.yandex.ru/get/6002...68dc5f0_XL.jpg

https://img-fotki.yandex.ru/get/1791...14f12f9_XL.jpg

Have to say that my view as to the likely cause is shifting towards a fuselage breach either because of a bomb or centre fuel tanks disruption - or the first causing the second.

I wonder whether the armchair experts here should not be giving at least equal attention to fuselage disruption as to the HS and VS, because as someone lese said, that discussion becomes an academic exercise if it was not the primary cause.

I hope also that we can more conciliatory towards Egypt- if this was a bomb (or perhaps even if it wasn't) it has had just the effect the terrorists wanted. If we are to show them that they won't win, we need, if Egypt allows us to, to help the Egyptian authorities correct any security breaches and help the Egyptian tourist industry to get back on track as soon as possible

Kulver

Thanks for putting these two pics up together.....Interesting the metal X brace is missing..the hole is from the cable bundle ripped out that was attached to the X brace.

The fuel line? seems long .....disconnecting somewhere into the tail.

The photos posted by Kulverstukas appear to show four major attachment eyes for the rear section of the fuselage on the intact photo.

The photo from the crash site clearly show at least two of those attachment points have fractured and pulled out of the support frame at what would be the top surface while leaving the support frame relatively undistorted.

That would imply that the tail section broke away downwards in relation to the rest of the aircraft.

Triumph61, the burn/heating pattern you can see on that skin for me is consistent with fire on the inside on the ground, when thin skin heats up fastest.
I have never seen a frame/stringer reinforced (and chemically milled) skin with heat damage caused in flight, but I would assume it looks exactly the other way around, heat is best dissipated to airflow at the thin skin, because of that stringers and frames see the most severe heat and hence damage.

What we can agree for sure is heat damage from the inside, just below the floor. As the floor was destroyed at impact, it is hard to believe that it was a barrier for the fire on the ground...

Around the Pieces on the Ground is no Burn Marks to see. Piece 2L is lying ~20m away from Fuselage, and the Burnmarks at the piece is Opposite from Fuselage
http://img5.fotos-hochladen.net/uplo...brhgaq7uwz.jpg
http://img5.fotos-hochladen.net/uplo...mn548wq30g.jpg

@triumph61 - Door2 panel
 

I would expect chemically milled skin and not a bonded or rivetted doubler.

What strikes me most is that you have severe fire damage at the grey lower part, and almost clean white upper parts of this panel. If you look at the panel from the inside it is shows the same. Not even soot.

The impression that i get is that the section either landed with the crown open (higher probability), or opened on or just after impact (lower probability). That then the fire started to consume the lower part of this section. And that at some stage the rescue teams may have used the white crane to drag this part out of the fire.

When you look at the AirAsia fuselage you see a flattened fuselage. So why is this one different. First difference is seawater vs rocky ground. Second difference is probably more of a rotation of the forward section and wing combination just before impact.

You might compare it to the IL76 coming down but with the rotation more planar (flat).

Would be interesting if others have another view of how you could connect these dots.

Really? I suspect someone if playing for time.

Several times I have been selected for such testing after passing through the metal detector / scanner. How come airport security can test me and my carry-on in 30 seconds.

Sure thats just one test, and they will be running thousands of samples. But "at least a week."

Revisiting the satellite images of 01 november for some speculation... I'm pretty sure the piece at the top is the tail section. Cone at the center or left, HS (grey, no shadow) at the bottom, perhaps? "Tail", "left cone" and "HS" objects sit approximately 900, 750 and 1050 meters ENE (perpendicular) of the recorded path, respectively. The "tail" object ~200 m after recorded vertical speed went negative, and the "left cone" object ~200 m before same point, in the direction of travel.

If 11:25 is EET/Moscow time, then this was 08:25 UTC, at which point the sun would be at 160 degrees azimuth (SSE) and 43 degrees above the horizon, according to WolframAlpha.

Autopilot disengagement timing
 

The chairman of the investigation noted that Autopilot1 was engaged before the event, and remained so till the end of the recording.

I wonder what is considered to be the minimum time by commercial pilots to disengage the autopilot in a severe upset event. In two cases:
a. instinctive reaction,
b. fastest reaction time after fast analysis (in quite a few general (=not specifically A/P related) cases there is talk about 12 seconds...),

And do different airlines have different default (training) procedures? Do you go to the button on the stick or do you go to the buttons on the 'glareshield'. The first procedure makes it easier to have an instinctive reaction. The second requires more consideration, and automatically takes longer.

To this day pilot incapacitation has not been an item.

From the beginning we are guessing on the root cause of the following sequence of events. One of the first events in that sequece is the rupture of the cables to the flight recorders as the voice recorder only shows the beginnig of a more intensive noise. So we can assume a cause that from one instant to the next broke those cables. What could have that effect?

A failure of the structure thru fatigue or lack of maintenace is to expect when there are heavy flight manuvers, not under smooth conditions as the flight was close to reach FL320 at safe air speed. Engines probably running at less than 100%.

Weather conditions cavok, no known shear winds (guessing).

Then loss of control and brakeup of the fuselage, beginnig? with the tailsection into 3 parts and the ripp off of the outer parts of the stabilisor. all of this in the first seconds of the crash sequence.

What cause would explain this?

If the Autopilot was engaged then it doesn't matter what the pilots were doing as any 'flying' input from them would show on the flight recorders.
Unless you are suggesting that there was an event that they were unable to correct, in which case this would also have been shown in the flight recorders.
FF

Normally I don't comment on these threads, this times however I followed the thread a bit more closely. On thing I didn't see mentioned here before is that when the event happend the ACT was propably just becoming empty (total Fuel on Departure, around 21 tons according to the documents published by Metrojet, and the Wing+CWT Tank can take a total amount of around 19 tons), this might be somehow related. Does anybody know the pax load for the previous flights? I noted that they landed with 17 tons of fuel remaining on on flight, according to my calculations (and obviously depending on the MLW of the specific aircraft - there are several weight variants available to airlines) they should not be able to upload more that around 110-120 passengers on that flight...
RE: A0283 The autopilot is disconnected with the instintive button on the side stick. The button on the FCU is only used to engage the AP - a disconnection with the FCU button is a "involuntary disconnection" (according to Airbus) and not normally used. It would not take more that 2 or 3 seconds to reach for the stick and disconnect the AP. However in many non normal situation disconnecting the AP won't be the first action, as the AP is able to handle most malfunctions and removes a lot of workload from the crew in a potentially critical situation. But I guess in this case (rapidly developing unusual attitude) it propably was the first action (if the AP did not disconnect by itself anyway...)
RE: Funfly If you give a input on the sidestick (with enough force to overcome the lock) the AP will disconnect anyway...

Food for thought
 

Food for thought
We still have no confirmation of explosive use. Could a bomb really have caused the selective damage we are seeing?
One of the earliest declarations from the authorities said the accident was caused by an external source.
A bomb in the aft cargo hold may have caused the disintegration of the aft fuselage but why would it have forced out the HS taking the rudder with it, and cleanly ejecting the tail cone and APU leaving the rest of the empennage relatively intact. Apparently the ACTs didn't explode since the aft fuselage panel fragments are not burnt. Following the DC10 accident outside Paris on 3 March 1974 when the aft cargo hold door departed causing deformation of the floor panels and seizure of the controls the regulations were changed so that cabin decompression would not cause break-up, even with the loss of a cargo door. Also crack stoppers at the frames reduce disintegration. So unless it was a huge bomb I think it unlikely that the fuselage would have disintegrated. The PanAm 747 was an even older design than the DC10 so was more vulnerable.
A bomb under the HS would have destroyed the FDR and CVR which are located there and they are in pristine (paint) condition.
What could have caused such sideways moment as to:
- distort the forward fuselage in relation to the wing (see the debris pattern)
- cause the disintegration of the rear fuselage
- cause such gyroscopic forces as to break off the cantilevered part of the engine pylons including the front spar attachment fittings with the engines, and cause their break up?
With the wing leaking fuel from the engine fuel supply lines and possibly the pylon attachments could this explain the scorched fuselage panels and engine parts? The burning fuel supply lines would immediately cause a fire around the engine and eventually ignite the spray of fuel or vapor coming from the ruptured tanks?
The second part of the HS to be found had major damage to the outer half. Could whatever caused that damage have caused all the rest???????????,

Triumph61 we have both HS (external parts admittedly less of the right one) but you aren't showing that? we also have the majority of both wings.

am I misunderstanding the meaning of your pinky beige colouring?

@Flo121142
 

Would you estimate this as being in the 2-3 seconds reaction time range too?

@A0283
The Piece 2L was not moved by white crane or person. You can see this Piece placed on this Pic. That Pic was the first what was published and you can see the Smoke.
http://img5.fotos-hochladen.net/uplo...myoxqlwvbn.jpg

A0283, Perhaps I am not following your thinking? For the A320/A330/A340 types flight control actions/inputs are protection-limited in Normal Law and would not cause the loss of the THS or the breakup of the aircraft. If the aircraft were in Direct Law with no such protections, it is doubtful that swift, full deflections of the sidestick would break anything

I started a google map to chart the debris field. Based on the satellite images and images from the ground this is what i have so far...

https://www.google.com/maps/d/edit?m...Vw&usp=sharing

A0283, yes, but "overpowering" the AP would be unvoluntary disconnection as well, i.e. not a normal way to disconnect the AP. But I guess it should not take more than 2-3 sec (I don't know the exact force required, it might be in some maintenance manual, but I don't think its more than 3 or 5 kg or so...). But as others have said I think it highly impropable that some sort of incapacitation caused this event (the aircraft is protected,in normal law the only way to overload the aircraft would be through massive rudder inputs...)

Kulverstukas, you have the sides wrong paired, left/right right/left.

Good one Kulverstukas - that's exactly what I've just been looking at. I'm guessing the 'slots' in the tail cone separation ring(?) are where the lug of the HS centre projects out behind the pivot point. Looks like the lower tail cone attaching lugs have pulled off the end of their respective box sections and an area of frame is also missing directly above on each side - where the HS pivot mounting attaches to the lower part of the fuselage.

Also - looking just above the slot on the left side of the APU cone (where the top attachment of the HS pivot mounting would have been) is that just normal muck, or does that look like an area of sooting on an otherwise apparently fire-free tail cone?

It doesn't matter. What I want to points is: top panel and holes for center pivots seems undamaged. Low panels bears marks of hit from lower pinions.

It means that HS leading edge travels down much more than allowed.

The lower end of the HS pivot mounting let go on both sides and swang backward on the top attachment, breaking the frame of the separation ring and prising the APU cone away at the bottom?

Otherwise - the HS pivot somehow spontaneously let go both sides (appears totally implausible), dropped below the slot and the attaching lugs of the HS centre punched into the APU separation ring, to the same effect?

'Pinions' - that's the word I was looking for.

Flo
 

"I noted that they landed with 17 tons of fuel remaining on on flight"

Can you point us to where you see 17t ? That doesn't make any sense to me.

HS issues
 

#2036 (permalink)

Just a guess- since we have not seen any HS "wing box " structure- it may well be that that structure along with jackscrew attach points and surrounding ' skin' has been removed from wreckage after cutting out the CVR and FDR to show what was found almost immediately.

That would include some of the attach lugs/points of the VS- which are missing. Some of the 'damage' to surrounding parts as seen may be the result of on the ground dissassembly to load on truck(s)

As to the obvious bending -breaking off of HS near simultaneous- IMO that could be caused by simply breaking the jackscrew or its follower or its mounting points allowing the HS to move towards being a flat plate to the airstream. - evidenced by the pulling down of the fuselage ret he tension unzipping of upper half forward of the AFT door. What caused the breaking or slippage is yet to be determined

Until either the HS ' wing box ' is found or revealed- we have probably reached the practical end of a reasonable analysis-

Explosive residue is another issue re initiation and where in aircraft :ugh:

Oldchina, On the extracts from the Flightlog - its on Flightlog page 26916...it says remained 17000kgs, Uplift 3930kgs giving a total of 20930...it seems to be a case of rather extreme tankering as the rotation was DME-LED-SSH...

JDD1 the CVR and FDR are located in the cabin above the rear lavatory not under the HS.

Vnav path, thats one with 7 tons (the accident flight), but there is also a previous one with 17t, page 26916...

Looking back at photos of the Hudson plane, it's possible to see pins connecting the two plates of the HS pivot hanger above and below. So once the HS goes down beyond a certain angle, the bottom edges of its attaching lugs will collide with the lower pins, twisting the hangers backward at the lower end and pushing onto the APU separation ring.

Between the twisting of the hangers and the sudden downforce/drag, you suddenly have a whole lot of forces at work on the tail of the aircraft.

matkat

http://www.pprune.org/rumours-news/5...ml#post9171991

other than a bomb...
 

A central fuel tank explosion would cause an instantaneous catastrophic failure. I don't know how that can be ruled out given what we know, although I presume actions taken after TWA800 have reduced its low likelihood to even lower.

@mudman

I have been doing something similar in Google earth, a couple of comments

- i think that you last reliable location position could be added to, the flight radar 24 S data indicates that at 04:13:15 the data starts going nuts, at 30.149689 34.178521, this is just to the west of the debris field and could indicate the start of 'event'.
- based in photos i think that the most east wreckage (30.168889, 34.171111) is an engine. This is determined from emergency vehicles and other wreckage in the background of photos.

The desert is hardly a hostile topography for finding such pieces.