According to the same FR24 blog post, "Autopilot Target Altitude" was 32 000 feet, by the way.

Correct, the first photo shows the tailplane of the 2014 August An-12 crash near Tamanrasset. However the inverted right wing is a genuine photo of this accident.

From photos published so far there appears to be at least two major areas of wreckage, matching initial reports of ground witnesses:

The nose section, with upper part of the fuselage crushed, implying ground impact inverted. The impact was not strong enough to disintegrate the entire section, which rolled semi-upright after impact. On the video released by RT it is possible to see on a few frames for a split-second that the severely burned center section and wings (also in an inverted position) are not far behind, suggesting that the wings with the center and front section came down in one piece. On some photos of the wing it is clear that slats, flaps and landing gear are fully retracted.

The tail section, which fell almost vertically and was crushed at the bottom, the impact also breaking the main spar of the VS. No trace of fire, and also no other wreckage is visible in the background on photos taken from different angles. The entire tail-cone section housing the APU and the entire HS structure is missing aft of the rear door and the pressure bulkhead.

All this, together with reports of a large debris field, seems to confirm an in-flight breakup around the time radar contact / FR24 data stream was lost. In the mean time, Egyptians have denied there was any communication between ATC and crew.

If this is correct, there are three possible causes:

A) Catastrophic failure of key flight control surfaces or loss of structural integrity, which rapidly place the aircraft into attitudes that cause structural breakup due to aerodynamic loads. This is also consistent with a rapid drop in airspeed quickly followed by a complete loss of transmitted data.

B) Inappropriate crew action which results in same scenario as above. Given the various envelope protections on AB this can only be achieved intentionally by degrading to direct law. A stall and subsequent blundered recovery would not cause this. All recent LOC accidents had an out of control but structurally intact aircraft hit the ground. Intentional crew action, while also having some high profile precedents, is highly unlikely at this stage.

C) Onboard explosion (bomb) which achieves the same as a structural failure. This would be the likeliest under given circumstances, however knowing the likely motives success would immediately be claimed and advertised. The fabricated IS video appearing 8 hours after the event lacks any credibility, and there were no other claims of responsibility, so again unlikely at present.

Given all above, scenario A) as implied by the Egyptian authorities (who are the only ones having access to detailed information at present) is a plausible one. It is thought provoking that the rear tip of the fuselage with the horizontal stabilizer appears to have separated from the rest of the tail section while in flight, while in many accidents we have seen the tail section retain most of its structural integrity even after a severe ground impact. Whether this was cause or effect remains to be seen, however in this context the 2001 tail-strike may be more significant than expected.

This may be or may not be a terrorist act but I commend the airlines who as a precaution have stopped overflights of the Sinai. A MANPAD I agree will not hit an airliner in the cruise but there is so much military hardware that was taken from the Libyan army during the revolution who knows what has fallen into these nutters hands.

The usual practice in Russia. Just as raiding the offices. So don't think too deep into it. The next news will probably be that some embezzlement was discovered. Which also shouldn't surprise anyone because embezzlement is also a standard practice in Russia.

As it is in several other jurisdictions such as France, Germany, Canada, Japan, etc. Deaths have occurred, which mandates a judicial investigation that is separate from the accident investigation. It is perfectly normal practice everywhere that documents related to the accident flight and aircraft are immediately impounded by the authorities.

I just wanted to give some answers to questions in this thread.

* All data from flight #7K9268 were picked up by FR24 receivers, which means receivers that are equipped with a GPS to get correct timing.

* FR24 is saving ALL received data in all FR24 receivers for last 4-8 hours (the full data volume is too big to be stream in real time) and in case it's needed the data is download from the receiver manually. In this case the raw data has been downloaded from 3 receivers that were picking up data last 30 seconds. Except for autopilot-data, none of this data has been published yet but confirms the data that has been published. In this data IAS and TAS are probably available but needs to be verified before it's released.

* There has been some confusion about the vspeed data. For MLAT flights vspeed data is calculated on FR24 side. For ADS-B flights vspeed data comes from the transponder. In this case the vspeed data is fluctuating too much to be correct, but it shows that something very dynamic was happening with the flight last seconds. The same fluctuations are visible when looking on data from each individual receiver one by one.

no. All it shows is that the data is incorrect. Incorrect data cannot show what was happening to the aircraft at that time

What you are describing is of course a function of the software that's displaying the received data, not the receiver itself.

And it's not necessarily related to "incomplete packets".

Those analysing the FR24 data will have noted that every row in the table contains a complete set of values for lat/lon. altitude, track, groundspeed and VS. But that's not what actually happens - the aircraft never sends all those parameters simultaneously as the DF17 squitter packet isn't long enough to accommodate them all.

Instead, they get sent in separate packets and FR24 simply carries over the last received values for those parameters that aren't part of a received packet. That's why, for example, the lat/lon values at 04:13:12 and 04:13:13 are identical, which is impossible unless we're talking about a helicopter or a vertical dive/climb with zero groundspeed. :ugh:

So, essentially, the only values that can be taken at face value are those that have actually changed compared to the previous row in the table.

And even some of those are suspect - I have yet to see any explanation of the apparent 5g deceleration at 04:13:00 other than the timestamps being out of sync, GPS/NTP notwithstanding.

That video is no more real than the tooth fairy or the Easter bunny. ISIS videos are typically high quality and well thought out. Surely the real money shot would be the entire crash sequence including hitting the ground. Only two seconds post 'missile strike' is filmed. I just don't buy it. If it as due to sabotage it will be from within the jet.

The fact that the MetroJet management have done a runner to Thailand speaks volumes.

I have over the past decade been in and out of HESH hundreds of times. Security was merely an act of going through the motions and ticking the boxes. I have little reason to believe that anything has changed.

On that basis, I am incredulous as to why a terrorist act has been ruled out with such vigor. In light of the I.S. claim to having brought down the aircraft, my incredulity remains.

Note : I am NOT saying this is the result of a terrorist act, I am merely saying it cant be ruled out YET.

Source please.

IS in Sinai have said that the video circulating is fake. Or rather... real video... not of this incident.

As noted, they are very particular about production and videos often are released days after an attack.

Strictly speaking, since FR24 only reports lat/lon to 3 digits after the decimal point, 0.001 degrees of latitude is 100 m, and the aircraft is only going ~100 m/s at that point, it's not impossible for two adjacent packets to have the same coordinates.

Presumably, the velocity parameter is airspeed and it's taken from the pitot-static system. Explosive decompression at 04:13:00 could explain the fluctuations both in reported altitude and in airspeed. I don't think that there was a timing issue, since reported lat/lon values progress smoothly.

What makes you think the altimetry system in an airliner category airplane would be affected in any way by an explosive decompression? All static and dynamic pressure ports are on the outside of the aircraft, hopefully...

Explosive decompression means a shock wave propagating out from the decompression spot. It only takes about 0.5 psi of overpressure to make the barometric altimeter read 28000' momentarily instead of 31000'.

Or it could be something totally unrelated, of course.

P.S. Found this paper, doing numerical simulation of the blast wave from explosive decompression of an aircraft. It calculates maximum overpressure of 1.15 kPa (0.17 psi) at the distance of 50 m directly forward from the point of decompression, using TWA 800 parameters (altitude 15000', Mach 0.50). Here we have higher speed and nearly double the pressure differential, so 0.5 psi is plausible.

OTOH, if this were a Buk type surface-to-air missile, we have this simulation and it estimates peak overpressure on the order of 100 kPa / 15 psi at the distance of 10 m from the point of detonation, and I'm not sure if the pitot-static system would even continue to function after a such an impact.

Thank you for sharing. Maybe we can look at it like this?

http://picload.org/image/pldddrl/incident.jpg

Few random thoughts
 

Just a few remarks

Given this accident location I'm pretty sure that flight was within both IDF and Egyptian military radar range (maybe even USAF AWACS). Any SAM launch (if there was one it wasn't a MPADS for sure) would have been spotted.

Another point is the amount of information - not necessarily relevant btw - that can be inferred out of ADS-B. Many have clamored for real time flight tracking... we are getting quite close !

Lastly a question: who will be investigation this (regardless of ICAO regulations) ? I feel that French BEA might emerge at some point... not sure the Russians would be happy about it but it still might be the fattest / most relevant approach.

Was there anything heard from Israel? Can hardly imagine that they do not permanently, carefully and accurately monitor this airspace, which is just across the border that was a battlefield may times in the past.
If they did (monitor) they could at least line out some versions discussed...


Sorry if I overlooked anything on this matter.


Concerning MANPADs, IMHO, why not to consider more serious stuff that jihaddists took over in Lybia during the chaos in that country? There were C-125 and even C-200 there...

It's marketing...

Just to make some comments to Metrojet/Kolavia info

- Company (it's holding of travel and charter companies) is half owned by Turkish citizen.
- Aviation part is operates since 1993.
- There was two hull losses since, both with Tu-154

There is a lot of speculation lately of poor financial state (unconfirmed), poor maintenance complains (unconfirmed or denied), salary delay for flight crews and pilots forced to fly broken planes (sources suspicious).