BREAKING NEWS: airliner missing within Egyptian FIR

[Vinnie Boombatz]

How it works - Flightradar24.com - Live flight tracker! (http://www.flightradar24.com/how-it-works)

"The primary technology that Flightradar24 use to receive flight information is called automatic dependent surveillance-broadcast (ADS-B). Aircraft gets its location from a GPS navigation source (satellite). The ADS-B transponder on aircraft transmits signal containing the location (and much more)."

Implication is that the altitude and groundspeed are from GPS. No air data.

Next question is the location of the GPS antenna, ADS-B antenna, GPS and ADS-B avionics on this airframe.

[oleostrut]

GPS reading will be wildly inaccurate on an inverted, gyrating, tumbling and spinning metal structure. Unless the receiver is at dead center of gyration, it will give unusable measurements, not to mention the time the antenna is shielded from satellite view.

Operated as intended, it does well.

[hamster3null]

Flightradar24 has released a revised data set:

Metrojet 9268 Extended Mode-S Data Decoded | Flightradar24 Blog (http://www.flightradar24.com/blog/metrojet-9268-extended-mode-s-data-decoded/)

Most important additions are GPS-derived groundspeed & vspeed. As before, there's rather sudden transition from business-as-normal at 04:13:14 to a 8000 fpm descent at 04:13:18, followed by a couple of phugoid oscillations (though still continuing to descend), and recording stops at 04:13:39 with vspeed of -26000 fpm and groundspeed of 47 knots.
For some reason, all timestamps have been shifted, so 04:13:18 in the new spreadsheet corresponds to 04:13:01 in the original spreadsheet.

Barometric altitude exhibits a small anomaly (a blast wave?) at 04:13:13.7 and then goes wild.

Even with the abnormal descent rate, the aircraft has not been overspeed at any time (combined horizontal+vertical speed never exceeded 410 knots).

[thcrozier]

Those were frightenly high frequency phugoids, on the order of 8 seconds bottom to top. What's the expected frequency for an intact A321?

[Prada]

Implication is that the altitude and groundspeed are from GPS. No air data.

Next question is the location of the GPS antenna, ADS-B antenna, GPS and ADS-B avionics on this airframe.

ADS-B transmits Baro altitude - flight level. It also transmit GPS altitude - geometric altitude, but it is not used.
There are two antennas. one is on the roof and other is on the belly.
GPS antenna, obviously is on the roof.

[Smott999]

Would initial loss of HS/rudder - but not yet full tail structure - cause a phugoid cycle?

Followed by full tail empennage loss and ensuing tumble/disintegration?

Just trying to figure sequence of breakup....

[DaveReidUK]

Implication is that the altitude and groundspeed are from GPS. No air data.

No, ADS-B altitude is normally barometric, although there is provision in the spec for sending GNSS height.

Groundspeed is, of course, GPS-derived, as is true track. FR24 appear to use the terms "track" and "heading" interchangeably, though if they are decoding EHS data they ought to have access to both (and IAS, too).

[oldoberon]

No, it's missing the part BEHIND the red line in the photo.


the part aft of the red line is also aft of the grill in the skin and the drawing below shows that is just the muffler which I suspect is squashed into the cone


http://i68.tinypic.com/152hjy1.jpg

[Nightingale14]

Captain Chelsey (Sully) Sullenberger of US Airways Flight 1549 that water landed in the Hudson, said in a Google talk that the automatic protection from phugoid mode implemented in the Airbus A320, prevented him from manually getting all possible lift from the wings at four seconds before water impact, causing the crash to be more violent.

[oldoberon]

https://img-fotki.yandex.ru/get/9059/61625582.6a/0_147013_c9c8f095_orig

looking at this image and the drawing above the cone has broken at frame 78, so where is the heavy duty frame supporting all the HS operating parts.

BTW what are those rod two of which appear to be able to move in the vertical plane and two in the horizontal plane, are they part of this screw jack ppl refer to, and where is the heavy frame , is it at the back of the main tail plane section or in the desert?

thanks to A0283 for the image it shows the parts I was asking about at the rear of the tail section

http://i64.tinypic.com/2rmqjac.jpg

[MikeJ65]

To me, it appears that the HS and VS had to be damaged before the separation of the tail section. Had that section separated first, I don't think sufficient forces would have been generated to do the damage. The VS appears to have split which could only happen if the aft mounting points were pushed rearward relative to the front mounting points.

My sequence would be HS/VS failure (reason TBD), HS tore off tail cone/APU, tail section is torn off by tumbling or spinning, fuselage rear section now has an open end and is torn apart by aerodynamic forces up to the stronger wing box, remainder of aircraft catches fire and falls vertical, mostly intact.

While this doesn't rule out foul play, it does make it less likely. A bomb in the passenger compartment or in the cargo hold is probably not going to cause failure of the HS and VS.

[A0283]

Major components which i have NOT found yet on pictures ... but hope someone else has:

a. top and aft section of the vertical tail structure,
b. rudder - so we are close to having the four corners but are not there yet,
c. horizontal stabilizer - we now probably have one side, but the center box and the other side are still missing,
d. 4 of 8 passenger doors (it is easy to identify 3 in their proper position, *** 1 or maybe 3 without position, so at least 2 still missing),
e. both engines identified (including fans and spinners) - but left/right unknown, and apparent difference in burn marks and fractures,
f. APU itself not explicitely identified - muffler visible, and end cover of tailcone/exhaust found,
g. the majority of passenger seats *** by now 1 clear image from a Russian video of a triple-seat which separated from the plane at altitude, and 3+3 possible,
h. nose landing gear itself – but expect to find that inside the NLG box,
i. probably a number of large (top) fuselage panels - again some look very clean and untouched by fire, while others appear to have burned up,
j. all righthand side cargodoors - you would expect to find some as the fuselage appears to be inverted,
k. winglet of the right wing,

We do not know the status immediately after the accident. So we do not now how much of the wreckage has been moved early on. So at this stage we do not know from the pictures how much of the fuselage we actually see. It may well be that the fuselage has been 'raked apart' early on to extract the victims (which of course had priority). If the fuselage has not been raked, and is complete over its length, then the fuselage appears to be broken, and the broken sections positioned in a zig zag. But with some of the top panels lost before reaching the ground. At this stage, based on the pictures, it could well be that an aft section part is still missing.

What is rather unexpected is the difference in burn marks. On some parts the burning has been severe, while their direct neighbours appear to be untouched. A striking example appears to be the Main Equipment Center. The lower left shows burned wire bundles (isolation burned off but metal wires still 'springy'), but directly next to that they appears to be clean and untouched. The wirebundles at the back of the MEC look good too. Almost looks like a kind of flash instead of longer duration burning. Which gives hope for possible data extraction from a number of avionics boxes in the racks of the MEC.

[Newfie]

Olodberon....

RE: post 714... I think you and the guy you were responding to both missed the point. If you look carefully at the section on the stand you can see vent hole and a louver. Everything to the right of that is missing on the crashed piece. So what he is showing with the red line is that what is to the RIGHT is missing. As noted also in post 701.

But more importantly to me, if you compare that picture, with the above drawing, and then of the pressure bulkhead with the fire bottle, the crashed piece with the fire bottle shows a diagonal cut running top to bottom for front starboard to rear port sides. As if sheared at an angle across the longitudinal axis.

Maybe the bit aft of the pressure bulkhead is now just an empty shell and it crushed on hitting the ground. Then the APU is not attached to this fire bottle bit but to the cone pictured in post 715.

No clue if that is significant, just trying to get the bit ps to fit in my head.

[olasek]

The Russian-language media report that so far no traces of explosives have been found on the wreckage.

http://www.rbc.ru/society/02/11/2015...794715abbcf395

[Smott999]

Do we know the location of the presumed portion of the HS?

[oldoberon]

In the video you can clearly see the back end assembly and that heavy frame at the end of the main fuselage just aft of the RPB you can also see the HS being fitted followed by the rudder

https://www.youtube.com/watch?v=6OQigxFYIUg

BTW now realise those tubular parts are not the screw jack but have no idea what they are, there appears to be 4 lower and 4 upper, they may even be adjustable length like a turnbuckle, if so are they tensioning/strengthening devices for the frame to enable it to cope with loads from the HS, there are 2 vertical movent ones and two horizontal movement ones at top and bottom, it is hard to see the horizontal ones as they are gong forward and hidden by the structure, post 663 shows them from within the HS compartment looking aft.

http://i65.tinypic.com/160d1s7.jpg

looking at the left hand fuselage of the two, you can just make out the rear door , going aft as you get to the HS compartment the skin changes colur to a greyish shade, is thus the approx area of the RPB, trying to get a visual handle on the size of the HS compartment

[14CFR]

http://i.4cdn.org/pol/1446518047390.jpg

[oldoberon]

But more importantly to me, if you compare that picture, with the above drawing, and then of the pressure bulkhead with the fire bottle, the crashed piece with the fire bottle shows a diagonal cut running top to bottom for front starboard to rear port sides. As if sheared at an angle across the longitudinal axis.

1st I think you mean the firewall not pressure bulkhead, I made that mistake until corrected, working from front it is rear galley, rear pressure bulkhead, unpressurised area for HS stabilser controls, front firewall of next aft sect the apu.

However my reason for replying is to ask for a post number showing what you believe to be a diagonal crack, bear in mind all the pictures showing the firewall and firebottle the section is on its side the actual top is at the left

this is now in the same orientation as the drawing ie top is top

http://i66.tinypic.com/r6za8m.jpg

[lomapaseo]

So, what happened first? tail was broken off or something happened to the fuselage between wings and tail?

Close ... but move forward of the wings for that initiation sequence.

The two engine fans would have felt it also but the engine casing damage would be 90 deg out of phase

[RatherBeFlying]

In the preceeding photos of the section with remnants of the fin, there does not seem to be any tailcone structure below where the tailplane is mounted.

That indicates a downward overload on the tailplane mounts, keeping in mind that once the jackscrew or attachments failed, there would be no survivable outcome:(

[andrasz]

That is the LEFT Horizontal Stabilizer on the video.

On the below link there is a very good photo of the entire structure, which is attached to the airframe through hinges at the rear of the center section and the trim actuator through the large hinge at the front:

More of the horizontal stabilizer - Wandering Aramean (http://blog.wandr.me/2015/09/airbus-opens-mobile-to-the-world/attachment/020/)

The fact that the HS is shorn off flush with the fuselage side is indicative of failure due to aerodynamic loads. If the attachment structure would have failed, the HS would have parted in one piece (it is a very strong structure, in several prior accidents we have seen the entire tail sections with HS attached survive ground tumbles relatively intact). This in turn suggests that the entire tail section broke off in one piece, and aerodynamic loads snapped off the HS (and probably the rudder and trailing edge of the VS) as it tumbled (I cannot envision an attitude of an intact airframe that would result in this damage while keeping wings intact).

Kulverstukas' new photo of the tail section which we have not seen before shows that the upper part of the frame supporting the HS/VS structure is intact, and that is also the section where the tailcone cleanly broke off. (Here is a photo of tail section while under construction: http://blog.wandr.me/2015/09/airbus-opens-mobile-to-the-world/attachment/008/). The VS attachment structure is essentially undamaged, the buckling of the VS is the result of ground impact (the damage is such that it could not have stayed together in the air). As the tailcone and the tail piece were found close apart (both shown on the initial video and the satellite map of the wreckage) it is reasonable to assume that they remained attached for some time after the HS was broken off. The right HS probably took out the HS support hinges with a clean break (which is evident on Kulverstukas' photo), together with all of the lower fuselage up to the RPB, those parts have not yet appeared on any photos.

All this in turn would confirm that the initial failure occurred somewhere before the tail, and eliminate the RPB as a possible culprit.


@Kulverstukas, any snippets of information in Russian media regarding the location of the HS ?

@lomapaseo, could you elaborate what makes you suggest any initial failure forward of the wings ? To all appearances the wing and forward fuselage came down in one piece, while the rear fuselage disintegrated completely quite early (if not first) in the breakup sequence. Do you see any evidence for an in flight T/R deployment?

As for FR24, they themselves confirmed that data received during the upset cannot be considered reliable, especially GS & VS data which are all derived from 3D GPS position which itself is unreliable given the circumstances.

[_Phoenix]

By looking at tail wreckage with VS at horisontal, missing THS and rudder, you can say that the tail cone was expulsed like an airsoft bullet, it ripped off everything around it.

[thcrozier]

I've made this comment several times over the years here in this forum and I'll say it again:

I'm completely bilingual in Spanish and English. That fact gives me the advantage of knowing how hard it is to convey meaning from one language to another.

When I hear people taking translations such as "toy", or "brought down", or "external" across languages to literally convey the meaning intended by the speaker, I can't believe they have the experience to know they may not understand at all.

I may be wrong - I only know two languages; but that's what I think.

[nnc0]

Anybody know if this msn had ACTs or had fuel tank inerting?

[hamster3null]

To me, it appears that the HS and VS had to be damaged before the separation of the tail section. Had that section separated first, I don't think sufficient forces would have been generated to do the damage. The VS appears to have split which could only happen if the aft mounting points were pushed rearward relative to the front mounting points.

My sequence would be HS/VS failure (reason TBD), HS tore off tail cone/APU, tail section is torn off by tumbling or spinning, fuselage rear section now has an open end and is torn apart by aerodynamic forces up to the stronger wing box, remainder of aircraft catches fire and falls vertical, mostly intact.

While this doesn't rule out foul play, it does make it less likely. A bomb in the passenger compartment or in the cargo hold is probably not going to cause failure of the HS and VS.

We have difficulties explaining the outcome either way. It's hard for a bomb in the passenger compartment to cause VS failure directly, and it's also unlikely that standalone HS/VS failure would lead to an immediate failure of the pressurized compartment. I don't think it happened either with JAL 123 or with AA 587.

We basically need two explosions, one inside the HS/VS bay and the other inside the passenger cabin. The first would knock out the APU and split the VS between mounting points, the other would blow a hole in the roof and tear off the tail.

[peekay4]

Flightradar24 has released a revised data set

Metrojet 9268 Extended Mode-S Data Decoded | Flightradar24 Blog

Most important additions are GPS-derived groundspeed & vspeed.
Hmm, reading through the FR24 blog, they say all pressure data (pressure altitude, TAS, vertical speed) are unreliable right after the "event" around 04:13:13 UTC or 331 seconds into the published FR24 data.

If we plot again the data including the new GPS computed GS and VS, to my eyes at least still only very limited conclusions can be made:

https://s3.amazonaws.com/org.barkah.misc/Metrojet9268_altspeed_PK4.png

(Altitude data up to about the 347 second mark is from pressure altitude. Raw GPS-derived altitude is substituted afterwards with no attempt to match them).

After the event at 331 seconds, the GPS Vertical Speed remains negative until the end of data, averaging about -10,000 fpm. So that "zoom climb" reflected from the pressure altitude probably didn't actually happen.

That likely also means there's no real "phugoid" motion where the aircraft periodically regains some altitude before dropping again. But there are periods where the descent slowed down.

The TAS remain fixed at a few values throughout, so it is probably garbage past 331 seconds.

[andrasz]

still only limited conclusions can be made
Limited to asserting that up to 331 the flight progressed normally. FR24 themselves confirm, though with more subtle wording, that NO direct conclusions can be made from the data after 331. The investigators might be able to reconstruct some meaningful information by matching assumed antenna angles and fuselage dynamics with received raw data, but the numbers by themselves mean nothing.

However there is one aspect of the FR24 data which is intriguing. By now it is increasingly clear that an in-flight breakup occurred, with complete loss of control the moment the tail section broke off early in the sequence. Data continued to be received from the aircraft for 25 seconds after the start of the upset, which at least indicates that the relevant systems were powered and transmitting (never mind the data). Can someone with knowledge of the bus power/avionics systems provide a plausible scenario for this ? Is this indicative of the engine generators continuing to supply power until loss of signal, or would there be some automatic reversion to battery power (which would remain available as it is in the front bay) after the engines would have shorn off ? Given the G forces involved it is unlikely the crew would/could do anything.

[thcrozier]

Peekay:

Assuming the plane broke in half somewhere in the interval you've charted, I wonder if the data is coming from the back or the front?

Also, can you establish a time function between the peaks and valleys?

Your chart is impressive and brings all sorts of thoughts to mind, not the least of which is what would someone inside have experienced. :(

[peekay4]

It's hard to compute a function because we don't know which data points (if any) may be considered reliable. E.g., even the GPS-derived altitudes don't match the GPS-derived vertical speeds.

It is a stark picture that something catastrophic happened.

[jolihokistix]

(Cannot find the English language button on the Arabic website, but a long shot anyway to offer as food for thought.)


TBS/JNN (fairly reputable Japanese news source) reported on Japan Yahoo news this morning:
????????????????????????(TBS??JNN?) - Yahoo!???? (http://headlines.yahoo.co.jp/videonews/jnn?a=20151104-00000001-jnn-int)
that the Egyptian newspaper "Al Masry Al Youm", エジプトの新聞アルマスリ・アルヨウム紙は３日、エジプトやロシア、フランスの専門家からなる調査委員会の関係者の話として、ブ ラックボックスの解析結果を報じました。それによると、機内で何らかの異常が発生し、機体後方の右側部分の壁面が損傷した結果、 墜落に至ったということです。
(My translation Japanese to English from here: "reported on the 3rd, that people close to the specialist investigating team from Egypt, Russia and France have said that analysis of the black box data suggests the occurrence of some kind of abnormality inside the aircraft body, then damage to the right rear wall of the aircraft causing its resultant crash."

[9 lives]

they say all pressure data (pressure altitude, TAS, vertical speed) are unreliable right after the "event"

If the origin of the data considered is "pressure" wouldn't that mean it's derived from the static system? The static ports could have been sensing wildly varying airflow if an "event" caused departure from controlled flight?

I'm not knowledgeable on FR24, so cannot comment about the value of that data, but in general, perhaps civil data gathering is reaching a point where instantaneous information is available at previously unseen resolution? There's just more to consider?

[peekay4]

Pitot-static system, so you have both dynamic and static pressures. There are many factors which can make their reading unreliable, including pressure changes related to the event, the changing orientation of the aircraft or sensors, and of course physical damage to the system itself.

[thcrozier]

ENOUGH?

Personally I think FR24 is improving all the time. Progress is difficult for us old guys to accept, especially when we thought we had the world all figured out long ago. I feel it as much as anyone. Though sheetsky for us.

FR 24 is not perfect, but has it shown anything demonstrably wrong in its overall picture of what happened out there on the northeastern Sinai Peninsula?

[FDMII]

ENOUGH?

Personally I think FR24 is improving all the time. Progress is difficult for us old guys to accept, especially when we thought we had the world all figured out long ago. I feel it as much as anyone. Though sheetsky for us.

FR 24 is not perfect, but has it shown anything demonstrably wrong in its overall picture of what happened out there on the northeastern Sinai Peninsula?

thcrozier, I agree with your comments on improvements, but I don't see a wide distribution of this kind of data as "progress", first because very few viewers are capable of meaningfully interpreting flight data; the experienced, old guys and gals have a tough enough time!, (remember the AF447 thread after the recorders were found...anything but conclusive).

My view is that interpretations without knowledge and experience is just this side of guessing and for many is short-term, non-serious engagement.

Under the heading of the old phrase, "everyone's an expert", I hasten to add that we dwell in an age in which it is generally thought of as impertinent to claim expertise, experience and knowledge when actually one has been doing such work for decades, and instead believing that because the technology exists, everyone should get "flight data" and have the right to read the tea leaves, etc., etc. But I have seen far more incorrect conclusions drawn over the years than insightful, correct conclusions drawn regarding what actually happened. In my view, many of the posts on this and any thread post-accident, illustrate this phenomenon.

I am not being critical of speculation or even rumour and I mean no disrespect for those who built/are building FR24 is intended. What is instead intended is a clear caution that while the technical capability exists to capture a few parameters, (less than are required by the FAA for this age of aircraft, it should be understood), that is less than half the battle when confronting what the airplane/crew/environment was actually like and what actually occurred.

[andrasz]

compare FR 24 data with FDR data
If our hunch of the tail separating early in the sequence is true, there will be no FDR data to compare to (though perhaps the QAR will hold some recoverable data).

[Icarus2001]

Not at all, the garbled data is consistent with the in-flight breakup and unusual antenna attitudes. Problem starts when people analyze that garbled data and start to draw conclusions from it.

Exactly my point.

first because very few viewers are capable of meaningfully interpreting flight data; the experienced, old guys and gals have a tough enough time!,

Of course.

As in 'the plane fell out of the sky', no. But trying to use the questionable data to explain why is fallacious and pointless.

Yes, yes, yes.

Pitot-static system, so you have both dynamic and static pressures.

The pilots and therfore, ground stations CANNOT read static source information. It all goes through ADCs (air data computers). By the time some data is sent via ADS-B then dealt with by a ground station it has been processed so much it is impossible to draw a conclusion about what a static port was "seeing".

From FR24 data we can say:

The aircraft went UP in a steady climb and came DOWN in an erratic uncontrolled fashion.

Which would be evident WITHOUT FR24 data as the wreckage is now sitting on the ground.

Any other "conclusion" or "theory" people try to derive from the data is purely supposition.

[peekay4]

The aircraft went UP in a steady climb and came DOWN in an erratic uncontrolled fashion.

Which would be evident WITHOUT FR24 data as the wreckage is now sitting on the ground.

That's actually not correct.

If we only had the wreckage, then for all we know the pilots might have descended the aircraft controllably for some time (e.g., to attempt an emergency landing with no comm) before an eventual breakup in the air, say at mid-altitudes.

The reason we can surmise that there was something sudden and catastrophic near cruise altitude is because of the FR24 data, as reflected in the graphs.

[wiggy]

If our hunch of the tail separating early in the sequence is true, there will be no FDR data to compare to (though perhaps the QAR will hold some recoverable data).

Yep, of course. In hindsight I should have written "if we can compare FR 24 data with FDR data."

All FR24 confirms is the blindingly obvious that something catastrophic happened at altitude....IMHO it's pointless using FR to attempt forensic analysis.

[Sokol]

https://s3.amazonaws.com/org.barkah.misc/Metrojet9268_altspeed_PK4.pngmany thanks for the Graph, Peekay. Could you please post an overlaping Graph of Gspd and vspd?

(Abnormality around 345 seems like a huge aerodynamic drag, but could also be an atmospheric or position based interference)

[RYFQB]

@ peekay4: I was curious about how accurate the GPS derived VS would be, so I made an experiment. In this .cvs (http://www.sharecsv.com/s/4339cb47dd5ce4ed5ff8b03ac75c63a9/experiment_alt.csv) you'll find a few new columns:

- c_alt contains the change in altitude from vertical speed over time
- n_alt contains the new altitude calculated from previous n_alt + c_alt
- d_alt contains difference between (baro) altitude and n_alt
- vs_alt contains altitude calculated from last trusted altitude and GPS VS after upset

The difference before upset is never more than a few tens of feet, and at the moment things start to happen (t=793.671) the difference is 19.5 feet. So for as long as the GPS precision remains good (which is not all the way to the end), I think the GPS VS and consequently calculated altitude is fairly trustworthy - at least compared to the old data.

My apologies to the folks who are not of the FR24 persuasion.

http://i.imgur.com/MmPQT8v.png

[olasek]

Any other "conclusion" or "theory" people try to derive from the data is purely supposition.
I concur. Attempt to over-interpret data of dubious quality. Let's look at the black box data - I bet we will see something completely different, the only problem being neither Egyptians nor Russians feel any sense of obligation to share this info.

[onetrack]

I have not seen any specific photos of any part of the cabin floor, the condition of which would be a prime indicator of any cargo hold explosion. A major overpressure event from the CH generally results in visible upward buckling of the cabin floor.
I have seen a photo of a truck-mounted crane lifting a fuselage section using a steel wire rope - operated with what appears to be a lack of care towards preserving any overpressure buckling evidence.
Fuselage wall or cabin floor components that are buckled again by careless lifting techniques would not assist crash investigators one iota.

The investigating (Russian) medics are stating that approximately one-fifth of the bodies have suffered severe burns.
This then extrapolates to mean that 4/5ths are not showing any severe burns, and that the fire in the aircraft was limited to approximately 20%, or less, of the fuselage.
What has also been revealed is that numerous bodies are severely fragmented - thus indicating the high possibility of an explosive event.
I would say that the Russian medics will know already, from examining the bodies - whether those bodies have sustained injuries consistent with flying fragments penetrating those bodies under high velocity, as in a nearby high-explosive event - or whether they were merely fragmented from impact with high-speed aircraft debris, as the aircraft broke up and impacted the ground.

[HarryMann]

Those were frightenly high frequency phugoids, on the order of 8 seconds bottom to top. What's the expected frequency for an intact A321?

Probably of the order of minutes so these aren't really true phugoids at all...

[Innaflap]

It will be very interesting to see the differences in how Putin and his government approach this enquiry vs the MH17 one. Hypocrisy is already evident.

[HarryMann]

...What has also been revealed is that numerous bodies are severely fragmented - thus indicating the high possibility of an explosive event.*.

Onetrack... it does not necessarily that all.
It might but much more likely is that the forces of deceleration, pitch, yaw and translational forces were very high.. which we suspect/know already.
Any bodies that were thrown free will likely have had additional trauma.

[peekay4]

@RYFQB

That's a nice experiment! It again suggests no phugoids.

https://s3.amazonaws.com/org.barkah.misc/Metrojet9268_computed_alt.png

@Sokol

Below is the correlation between GPS Ground Speed vs. Vertical Speed:

https://s3.amazonaws.com/org.barkah.misc/Metrojet9268_gsvs.png

[thcrozier]

I'm thinking there were phugoids. Most of us probably built model or paper airplanes as kids, and we all probably all saw what happens when the tail comes off. Not a ride you'd want to take but a tuck under to an high frequency inverted stall which may have developed into a spin.


I'm suggesting that after losing its empennage, the plane entered an aerodynamically stable maneuver which had a constant rate of change with respect to several variables - Included among them would be increasing air density, decreasing weight, changing center of gravity, and others. It would be a complex differential equation with all those variables affecting the frequency and amplitude of the oscillations.


peekay's chart has a certain symmetry to it and although it is beyond my mathematical abilities, I think it could be modeled.

[Toruk Macto]

Not sure how Russians feel about wearing seat belts while the ride is smooth if there anything like the people I see in my neck of the woods most would have them comfortable unfastened .

[andrasz]

I think it could be modeled
I'm sure it could be, however what happened to the rest of the airplane after the tail parted, and how that may relate to FR24 data is entirely incidental to the cause.

[silverstrata]

Flightradar data:

Quote:
The altitude value is derived via a pressure sensor, which can be affected by changes in pressure outside the aircraft. In this case, what we’re learning about the state of the airframe calls into question the validity of the altitude readings during this time period.


I think that what they mean here, is that if the aircraft had started tumbling, disturbing the airflow over both pitots and static ports, then both the altitude and airspeed transmitted will be unreliable.

In which case the Flightradar data may suggest that the aircraft lost control in the climb-cruise phase, and not in the descent. So the loss of control was immediate and catastrophic, and was the cause of the sudden descent.

Silver

P.S.
From the data-graph posted by Peekay4 in post 509, we see four data extremes within 12 seconds. If the data excursions were caused by airflow disturbances over the pitot and static ports, this could well indicate that the aircraft was rotating in pitch or yaw (or oscillating in pitch or yaw), every 3 seconds.

There was a video earlier of a Russian transport aircraft crashing, because of a loss of tail surfaces, and that was almost managing a 3 second rotation. Rapid pitch or yaw motion (without changing the altitude significantly) to disturb the pitot-static system could be achieved by a loss of tail surfaces, or by runaway computers/hydraulics. I am thinking of that 747 that had runaway pitch commands to the elevators on take off from Heathrow, many Moons ago. An elevator actuator had a transient oscillating glitch, but the other actuator kept the aircraft more or less stable.

Silver

[Reders]

However there is one aspect of the FR24 data which is intriguing. By now it is increasingly clear that an in-flight breakup occurred, with complete loss of control the moment the tail section broke off early in the sequence. Data continued to be received from the aircraft for 25 seconds after the start of the upset, which at least indicates that the relevant systems were powered and transmitting (never mind the data). Can someone with knowledge of the bus power/avionics systems provide a plausible scenario for this ? Is this indicative of the engine generators continuing to supply power until loss of signal, or would there be some automatic reversion to battery power (which would remain available as it is in the front bay) after the engines would have shorn off ? Given the G forces involved it is unlikely the crew would/could do anything.

The Transponder (source of FR24 data) may still operate on DC battery, loss of data could be due to equipment feeding transponder going invalid which may also stop the ADS-B transmissions, also as altitude reduces the FR24 ground RX could loose signal due to normal radar range issues.

What would be more interesting was if any ground ATC tracked the Mode A/C/S from this aircraft?

[andrasz]

any ground ATC tracked the Mode A/C/S from this aircraft?Yes. This can easily be deduced from position of last radar contact, which is very close to the main wreckage and well beyond the ground location of the tail and other rear fuselage debris along the flight path. Given the heavy military presence in the area, I'm sure there was primary radar tracking as well, from both sides on the nearby border.

[Sober Lark]

In the immediate aftermath of Flash Airlines 604 it was thought to be terrorist related but this was very quickly dismissed, even though retrieval was more difficult. I note the accident happened on 03/01/2004 and the final report came out on 25/03/2006, so all things considered, pretty quick.


If security in Sharam el-Sheikh airport wasn't up to scratch wouldn't you imagine some of the 900,000 British who visit each year and can compare it to UK airport security would have drawn attention to any perceived shortcomings?

[skridlov]

Having followed this thread since the accident was first reported I don't recall hearing how the investigation is likely to deal with the material remains of the aircraft. From the information available to date it's beginning to look as though examination of the wreckage for evidence of failure is going to be a critical component of the investigation. Would this material be moved or would the investigating team travel to Egypt? - I'd assume the latter.

Also, assuming that the absence of explosive residues on the passengers is being reported correctly (a big "if") would this eliminate the possibility of the event being caused by an explosive device?

[DingerX]

Folks, here's the rules:
1. At the moment, there's a lot of pressure on the press to report _anything_ that can conceivably be associated with this accident. As a result individual "unconfirmed sources", especially from the Tabloids, cannot be used for anything.

2. The FR24 data: They've now come out and given all the information you need: after the first moment, their data is unreliable. Altitude is given by GPS. GPS is not designed to give altitude; if you doubt me, download an app that spits out the raw data from your phone's GPS unit. Lat and Longitude will be precise, but altitude will be all over the place. To get precise information, most terrestrial navigation systems use something else, like looking up Lat. and Longitude on a Digital Elevation Module database.
Certainly, with enough time and controlling for enough factors, you *might* be able to fit that GPS data into a model of the aircraft's altitude. But spikes and other garbage are just not going to work. So, at the moment, the FR24 data are useless.

3. Rear Pressure Bulkhead. Yes, this was is what failed in JAL 123, and in whatever that Viscount crash in Belgium was. I haven't seen it credited with China Airlines 611, however. That was simply structural failure from an improper tailstrike repair. There seems to be a mindset: "Tailstrike = RPB failure", and that's dangerous.

4. A321 and tailstrikes. A321s have the longest bodies of the A320 family, and tailstrike with some frequency. When they do, they don't strike back at the RPB, but further forward. For example, someone scraped this a321 (http://news.aviation-safety.net/2015/01/24/inadequate-bounce-recovery-training-program-factor-in-airbus-a321-tailstrike-accident/) pretty bad, with the center of damage just below the Bulk Cargo Door. This means that, even if the 2001 repair were done perfectly, some other tailstrike might have doomed this aircraft. We've seen here the reports of pilots "not hearing" a tailstrike.

Now, to the tea leaves:

What we do have from the FR24 and the debris field is an aircraft that broke apart while climbing through 30,000 feet. From the photographs, the tail section separated from the rest of the aircraft, and the tail section itself seems to have broken into two parts: one part with the APU and tail cone neatly sheared, the other with half the VS, neatly sheared from the windows to the top along FR65, and, on the bottom, tearing down and forward of FR65 through the rearmost two windows and down to the Bulk Cargo Door (which isn't attached). This tail section is laterally symmetrical: left and right show more or less the same tearing. The horizontal stabilizers have been sheared clean, suggesting that they suffered excessive aerodynamic pressure.

Accidents on initial climb favors pressurization-related events: Fuselage cracks from metal fatigue, improper tailstrike repairs, door failure, and, sure, bombs rigged to cabin altitude. They all occur in this zone.
While any of these are possible, only one is favored by the information we have available.

[22/04]

So we are left, probably with a structural failure.

The next step would appear to be to decide if separation of the tail was cause or effect.

Presumably if we do not get an indication from Airbus quite quickly asking for examination of components etc. then we can conclude it is something that concerns only this airframe not a significant number of the Airbus A321 or 3 xx fleet.

[Sokol]

https://s3.amazonaws.com/org.barkah.misc/Metrojet9268_gsvs.pngThanks. As I assumed the data between 330 and ~343 looks like full Rubbish, after that you can see an increasing barometric Pressure shortly after an increase of Gspd and Vsp. This would fit an Pitotrod thats been used in false direction. (Aerodynamic Drag induced by an Rollover e.g.)
Then the "Airframe" must have entered a more "stable" regime which has been hold until the Generators went out.(If data are correct)

Concluding: Nothing that helps finding the cause.

[Ka-2b Pilot]

Quote from DingerX " GPS is not designed to give altitude".
GPS is as accurate in altitude as it is in Lat/Long. The accuracy in any dimension is dependent on line of sight to as many satellites as possible in different directions and planes. In the air it is very accurate under most conditions in all dimensions provided it is connected to an external antenna. On the ground in wide open country it is also very accurate, while in towns or very mountainous areas it can become quite inaccurate in any or all dimensions. A phone GPS will not work properly inside a large aircraft as the body is sufficient to block most satellites unless they have line of sight through a window and it needs a minimum of 3 or 4 to obtain a lock with minimal accuracy. I fly gliders and use GPS for height readings and it is extremely accurate, much more so than a barometric altimeter!

[dmba]

Why is there a general assumption the fire damage was only caused prior to the aircraft hitting the ground? The photos clearly show that there was an immense fire on the ground. Surely things would have been damaged/scorched/heated/sooted by this fire, not just in the air.

[wiggy]

I fly gliders and use GPS for height readings and it is extremely accurate, much more so than a barometric altimeter!

That may the case with a glider, but given the context of the tread what about relative accuracy in the case of a RVSM compliant airliner.

[WNTT]

i have mapped the RF24 data with the location of the pieces of wreckage, I can’t attach an image (how can I do this?) but a few findings that may give a bit more context to the crash site

- The south east debris field (containing the tail, but no confirmation of HS here) is located approximately 800m to the east from the flight path (@31k ft), and where the FR24 data starts going strange (04:13:14 onwards), indicating where the ‘event’ might have occurred.
- The north west debris field with the main wreckage is approx. 2km south east of the last FR24 data point, the nose of the aircraft wreckage is pointing south west.
- The main debris field is approx. 2.5km to the north west from the and tail debris field.
- The flight path is straight as an arrow until a time just after the ‘event’, then drifts to the west, then to the east a bit.
- The points at the end of the FR24 seem to be bunched up spatially, maybe indicating a rapid decent without much vertical travel.

This spatial data seems to me show that whatever the event was it was sudden and the plane became unflyable and came down quickly, the image shows this much clearer than the text.

Does anyone know a spatial location of the HS wreckage?

[rog747]

to the chap who posts these updates ao283

i have seen in photos both winglets - one is fairly intact
(but as the wings are now upside down the 'top part' is bent on impact)

and the other one is very bent and burnt (rhs?) but was recognisable

been looking for the photos but its eluded me

[Andy_S]

If security in Sharam el-Sheikh airport wasn't up to scratch wouldn't you imagine some of the 900,000 British who visit each year and can compare it to UK airport security would have drawn attention to any perceived shortcomings?

Passengers won’t really be aware of what goes on behind the scenes, either with checked baggage, cargo or catering / cleaning etc. What they don’t see won’t particularly bother them.

I’m inclined to wonder why, if security is – as alleged – so lax at Sharm, no one has attempted to smuggle a bomb on board an aircraft previously. If it were that easy, I find it difficult to believe it hasn’t been done before now.

[Ka-2b Pilot]

@Wiggy, provided the GPS is connected to an external antenna then it will work accurately, down to a few feet or less of the location of the antenna. In the air it will be receiving data from perhaps a dozen or so satellites at any one time which gives great accuracy. On the ground much less so as not only will it receive fewer satellites most of the time but it may also receive reflected signals from buildings which could cause spurious readings. Try driving along a motorway with one at a constant speed and and watch the fluctuations as you go under bridges, or the huge spikes if you go through tunnels. Imagine the latter effect on a fixed antenna on a rotating body where it is seeing a different set of satellites as it rotates. Mine will often tell me I reached 600 mph as I exited the tunnel (I had it set to record every second), with no signal in the tunnel it estimates position until you exit and it receives again, if there was a turn in the tunnel you will not be where it expected so it will correct it the next second, similarly if you change speed. This should go some way to explain what happened after the event in respect of GPS readings.

[FE Hoppy]

How about plotting the GS/VS as x and y. You will get the trajectory with the variations being due to thrust/drag of the tumbeling aircraft.

[RiSq]

Passengers won’t really be aware of what goes on behind the scenes, either with checked baggage, cargo or catering / cleaning etc. What they don’t see won’t particularly bother them.

I’m inclined to wonder why, if security is – as alleged – so lax at Sharm, no one has attempted to smuggle a bomb on board an aircraft previously. If it were that easy, I find it difficult to believe it hasn’t been done before now.

Just putting it out there, but it may be, Contrary to what the Governments say in their propaganda, that not everybody is itching to either blow up an aircraft nor Hijack an aircraft.

Let's face it - there's much easier places to bomb.

[hamster3null]

Not sure about exploding poop, but there was an incident in the 80s that involved a guy flushing a live hand grenade in an aircraft lavatory. The explosion punctured the APB and severed two out of three hydraulic lines, but the crew managed to land the aircraft safely.

[RTM Boy]

From we 'know' I see it like this.

The absence of any distress call would suggest a very rapid event. The size/shape of the debris field clearly indicates that the airframe break-up at altitude. The various tail parts and components/systems are identifiable and show only relatively minor signs of heat damage and at at some distance from the rest of the aircraft remains.

Based on various photographs, because the 'one piece' outlines are clear to see on the desert floor, the front section of the fuselage c/w wings must have remained largely intact until hitting the ground with little or no horizontal airspeed in a sort of upside down belly flop. Since the wings appear to have remained attached to the fuselage, it would seem to suggest that the fuel tanks did not explode until hitting the ground - after all I would expect them to be fairly full so early in the flight and had one or more exploded for whatever reason it would have blown the airframe into far smaller fragments...probably.

A single heat flash was detected by IR satellite at a time and location indicating a mid-air explosion of some sort.

The section of fuselage between the wings and tail disintegrated significantly, indicating that whatever caused the explosive event was in this area. If PAX seated in this area did indeed suffer severe burns (with those forward of this section suffering mostly impact traumas of one sort or another), then this would confirm that the event was centred somewhere aft of the wings.

The cause was either 'accidental' or foul play.

It is difficult to see how a structural failure of any sort would have caused a mid-air explosion - consider JAL123 and BEA706, or indeed AA96/TA981 for example.

Hypothesising for a moment, if the central fuel tank was largely empty, an 'accidental' explosion similar to that of TWA800 might have occurred. An engine failure might have caused debris to puncture the fuel tank.

If it was the result of foul play, there is no evidence of any projectile strike. However, at that altitude even a relatively small explosive device in the rear cargo hold would cause a break up. But would it explain the heat flash? Even if passengers at the rear of the plane do indeed show no signs of explosives on their person, it does not mean there was no bomb. They were severely burned anyway, so such evidence might have been lost.

I'm not convinced that the CVR and FDR will provide a clear answer and suspect that definitive explanation will be some long way off...

[Icarus2001]

Ka-2B pilot

GPS is as accurate in altitude as it is in Lat/Long.

No it isn't.

If you fly gliders I can assume you know the difference between height, altitude and pressure altitude.

A GPS altitude is expressed above what datum? Think about it for a minute.

The earth is not round, it is an oblate spheroid. GPS altitude is measured above a geometric model of the earth. In some places the surface of this model is above the "real" sea level surface and in some places below the "real" surface. WGS 84 is one such model etc

I fly gliders and use GPS for height readings and it is extremely accurate, much more so than a barometric altimeter! Perhaps you do but no it isn't.

Here is a link to a useful article on the subject with good diagrams.

GPS and altitude for hang gliding and paragliding | Cross Country Magazine (http://www.xcmag.com/2011/07/gps-versus-barometric-altitude-the-definitive-answer/)

Have a read and a think.

As I said earlier, the FR24 data is almost useless.

[ZeBedie]

Fuel/air explosion in the empty ACT, in the rear hold?

[lowca]

A single heat flash was detected by IR satellite at a time and location indicating a mid-air explosion of some sort.

Since the wings appear to have remained attached to the fuselage, it would seem to suggest that the fuel tanks did not explode until hitting the ground -

Was the heat flash confirmed as occured where plane was still in the air? Because even with the big bang at cruising altitude, I'd expect much bigger heat signal from fuel burning when plane crashed onto the ground.

[onetrack]

Why have Metrojet refused to release the cargo manifest? This only raises suspicion that something was being carried as cargo that should not have been, and that that cargo posed a potential explosive threat?
Alternatively, could something potentially explosive have been sneaked aboard in the cargo at SSH, that was not listed on the manifest?
From here on in, Russian and AB investigators are going to be very reliant on the thoroughness of the scrutiny of the airport security and the CCTV records, by Egyptian authorities.
This is not something that encourages reassuring thoughts about how any security breach, if discovered, will be treated.

[Kulverstukas]

Metrojet refused to release the cargo manifest

any proof?

[Kulverstukas]

I can read it with great doubt, but if someone wants this "crazy Russians on falling apart planes" there you go: Airline staff have revealed the cause of the disaster (http://www.microsofttranslator.com/BV.aspx?ref=IE8Activity&a=http%3A%2F%2Fvolgasib.ru%2Fskandali-4p%2F27091-finansovaya-situacziya-na-moment-katastrofy-v-kompanii-qkogalymaviaq-byla-kriticheskaya.html)

[Kulverstukas]

http://www.mk.ru/upload/entities/2015/11/02/photoreportsImages/detailPicture/3f/6c/7d/80/6451729_1539628.jpg

http://www.mk.ru/upload/entities/2015/11/02/photoreportsImages/detailPicture/9b/0a/6a/77/6505076_6080396.jpg

http://www.mk.ru/upload/entities/2015/11/02/photoreportsImages/detailPicture/ad/56/d7/0f/6469173_2821068.jpg
http://www.mk.ru/upload/entities/2015/11/02/photoreportsImages/detailPicture/60/41/b7/73/6480778_3816470.jpg

What's this? ^

http://www.mk.ru/upload/entities/2015/11/02/photoreportsImages/detailPicture/5a/da/3f/1f/6441063_9122365.jpg

[andrasz]

I would treat all reports of that "heat flash" with caution. It was reported, then denied, then reported to be something else not the aircraft. Until it is confirmed by an official US/RU source, I would not build any theories on it.


That being said, there seems to be no mention by anyone of the (one or two) auxiliary fuel tanks in the rear cargo hold, which is essentially a purpose-built ULD and a standard fixture of 321s on longer routes. If the rear fuselage disintegrates, those would be dislodged and ruptured, liberating enough fuel to produce a fireball if ignited.

[Icarus2001]

Both absence of seats photos and very small probability about some messing with the loo is because plane was still climbing at the point of event, so pax was seated and fastened and any loo excursions was prohibited.

Really. You think because the aircraft was still climbing the belt sign must have been on, therefore all pax were seated?

Amazing.

Are you a pilot? Do you fly as a passenger very much?

The belt sign in many airlines comes off after transition (FL100-FL150) if in smooth air and nothing visible ahead that poses a turbulence threat.

NB for the pilots, yes I know about transition down as low as A030. Trying to KISS

[Kulverstukas]

onetrack, cargo manifest, as well as all other paper are now in hands of Investigation Committee of RF. I think that Kolavia staff was strongly advised about security of investigation and punishment for any "leak" which can be traced back to person who can make this document available to public before official release.

[Kulverstukas]

http://aviaforum.ru/attachments/a321_2-png.500027/

(c) http://aviaforum.ru/members/mechanical-engineer.30813/

[andrasz]

Before we dwell too much on the absence of cargo manifest, a gentle reminder. This was a holiday charter flight, normally such flights are not permitted to carry commercial cargo, so the cargo manifest if existing at all should say NIL. (With 220 pax and their luggage, not much room for cargo anyway).

However SSH is a popular scuba diving destination, and every flight coming and going would have several sets of scuba gear as baggage on board. By regulation the scuba tanks must be empty and the valve open, however there is a similarly strict rule that all scuba tanks if left unpressurised for any period of time must undergo an internal corrosion inspection before filling and re-use. This is quite expensive (so much that more responsible divers rent at destination, makes more financial sense), so many are quite reluctant to fully empty tanks and sometimes there is a severe argument about this at check-in. Knowing Egypt, there is always the money...

IF a scuba tank (in worst case, filled with pure O2) ruptured adjacent to a full auxiliary fuel tank, that could make a pretty big bang. Wild theory, but perhaps not as much as the butt in the poo.

[Kulverstukas]

andrasz this theory was not unheard of (about scuba tanks) but also there was mentioned that to take own tank is too expensive so mostly diver lease them onsite.

Anybody familiar with 320/321 - where this trimmer part (on photos) is from?

[Icarus2001]

IF a scuba tank (in worst case, filled with pure O2) ruptured adjacent to a full auxiliary fuel tank,

Scuba tanks are filled with compressed air or sometimes Nitrox, which is air with a higher oxygen concentration.

Why would it rupture? Most modern tanks have a "burst disc" so when left in a hot car one day if filled too much they vent safely.

As mentioned above, divers do not usually travel tanks, pick them up locally, much easier. That is not to say it is not possible.

Why don't the co2 cylinders on every lifejacket under every seat "rupture"?

Why don't the on board pilot oxygen cylinders "rupture"?

How come the champagne bottles on board do not explode?

How come the tyres don't "rupture" on the rims?

:ugh:

[FE Hoppy]

Who dives with pure O2?

[handleturning]

Why would scuba tanks be filled with pure O2? You can't dive with it (it's poisonous below a few metres). A tank costs around £15-20 to service, from experience I really can't see why someone would deliberately check in a full tank.

[MartinM]

Who dives with pure O2?

You cannot, as you would die from. You will always have a mix.

[Prada]

Scuba tanks are heavy. average Scuba tank would weight around 20kg. But regarding Sharm el Sheik diving business, it is much cheaper to rent them locally for average diver.
Technical divers might want to bring their specialized equipment with them. Also deep divers use pure O2 for breathing in very shallow depths after very deep dives to get rid of excessive nitrogen dissolved in body.
But, all tanks that you take with you aboard, are required to be with open valves. Empty it means.
So, if rules were followed then scuba tanks pose absolutely no risk.

[Kulverstukas]

Pontius Navigator , I'm not so frequent flyer and also I mostly fly Aeroflot, but lately there is habit do not switch seatbelt lights off until complete leveling and advice to wear seatbelt buckled while ones are seated politely reminded by FA.

[fando]

@Kulverstukas

http://aviaforum.ru/attachments/a321_2-png.500027/

Where do come the yellow coordinates from?

I just tried to find the place on google maps. The blue point top left with the "4.00 km" label is the last known fr24 position, with a gps altitude of 26400f...

the blue point with the "0" label is the position where the trouble started...

[hamster3null]

Life jacket canisters contain gas at lower pressure (CO2 liquifies at 900 psi, diving tanks are compressed to 3000+) and they have a much higher safety margin because the weight of the canister is far less crucial.

Nevertheless, life jacket canisters still have to be build to meet certain safety requirements in order to be allowed on the planes. But, for example, CO2 bike tire inflation cartridges (functionally identical to life jacket cylinders) are banned onboard.

You don't dive with pure oxygen, but Nitrox 36 still has nearly double the concentration of oxygen, compared with regular air.

[Kulverstukas]

Just side note. Head of Investigation committee of RF flew back home from Cairo today without chances to visit crash site - yesterday he was not allowed because paperwork was not done and today because of severe weather at site.

[Kulverstukas]

As I now have couple of answers that part in question is from wing mechanization, seems it was ripped off in air because of no traces of flame.

[Pontius Navigator]

Kul, you are absolutely correct but compliance cannot be assumed.

Regarding flying over pressurized, that is a non sequitur. If cabin pressure does not leak then cabin altitude will be stable. If there is a leak cabin pressure will drop.

To retain an acceptable pressure the pressurisation will remain on longer. There would be no advantage in pressuring to 4,000 feet, bleeding to 6,000 and repressurizing to 4,000 ad nauseam.

I have been in at least one aircraft with a large gap, not a slow leak, plugged with a cushion and blankets, pressure didn't fluctuate.

[steve611]

A couple of minor corrections to the comments on diving with oxygen. Pure oxygen is neurotoxic above 2 atmospheres pressure, approx 10m depth with pure oxygen. The only folk who use pure oxygen are:
a) military divers, shallower than 10m and using rebreathing systems (no bubbles on the surface; a balance of risks) and
b) the rare really deep divers who use a complex gas mixture- at extreme depth this oxygen pressure equates to low single figure percentages of oxygen by volume, so the gas mixtures are carefully crafted using single gas cylinders.

[oleostrut]

"The specific details about difficulties with the door seem plausible."

Both aft doors were still attached to th remains of the tail.

Leaking door seals are not unknown. If pressure leaks are severe, it limits the altitude the aircraft can maintain set cabin pressure altitude.

Don't forget, cabin altitude is controlled by the outflow valve, essentially a big, adjustable hole in the skin.


Side Note: pressure leaks were easier to troubleshoot back when smoking was still allowed on aircraft.

[Kulverstukas]

Breaking Leak from Egyptian source - engine blast. (via Al-Masry Al-Youm)

[Prada]

Breaking Leak from Egyptian source - engine blast. (via Al-Masry Al-Youm)

If it really was an engine blast, I would suspect left hand engine.

[Kulverstukas]

More photos of parts here: Russian plane crash reveals ?no proof it broke up in mid-air', Egypt claims | Daily Mail Online (http://www.dailymail.co.uk/news/article-3301094/Terrifying-final-moments-doomed-Russian-jet-Plane-lurched-passengers-sucked-seats-external-impact-blew-jet-apart-flight-data-reveals.html)

Also "Egyptian authorities claim there is 'NO proof' doomed Russian holiday jet broke up mid-air - but investigators 'interrogate' driver who delivered food to the aircraft"

[Double Back]

During my professional airline flying career(B744) I kept on model flying, which has always been a great source for information, training reflexes and understanding aerodynamics. Both good and bad experiences helped me in flying full size. For some bad experiences I was lucky not to encounter full size.

Recently I have lost a (model) twin boom (turbine) jetplane due to flutter, causing the stab to separate completely. It happened at around 10-15m of altitude, flying in a shallow dive.
The sequence of the ensuing breakup went so fast, I and another professional airline pilot could not recall what exactly had happened. So fast, even to exclaim SH.. . That word came when all was already on terra firma....

The fuse was constructed of GFRP, stab and wings were built up balsa structures.
Is was a sudden bang and a cloud of balsa coming down, bigger debris tumbling down along the track.
From the debris path (stab found first) we could piece together that when the stab shed, the forward fuse and wings rotated 90 degrees down at full speed (200+ kmh), in a split second, causing the wings to be stripped of most of the covering and ribs, because of the enormous air loads.
The tank (some 5 litres) was catapulted through the topside of the fuse and was at the end of the trail. It was hardly damaged, still containing nearly all the fuel. Somewhere before that the engine was retrieved.
The "negative" G forces on the model must have been incredible.

I have thought a long time about this and started searching. I found a comparable, be it a tragic full size example:
https://www.youtube.com/watch?v=Nq77TMHzYXA

When the stab sheds, the nose of the Invader dives so quickly, that the wings develop an extreme negative load, clearly visible. Before they actually have time to break, the Invader hits the ground, killing all aboard.
This example may be slightly different, in that the explosion must have contributed in lifting the tail.

IF this Airbus did loose its complete stab in one go, for whatever reason, the ensuing negative loads must have rendered the pilots immediately incapable of any action.
In a very early phase the fuse must have broken up, wings plus a small part of the fuse tumbling down, engines "flying" on.
As far as I can see most parts hit with little horizontal speed.

[Pontius Navigator]

Breaking Leak from Egyptian source - engine blast. (via Al-Masry Al-Youm)

And the missing word?

Credible?

[Kulverstukas]

From this daily maily article, new photos:

http://i.dailymail.co.uk/i/pix/2015/11/03/15/2E10DD5100000578-3301094-This_section_of_cockpit_was_one_of_12_wreckage_sites_spread_ acro-a-2_1446563094964.jpg

Note that there no burning mark is visible

http://i.dailymail.co.uk/i/pix/2015/11/03/15/2E09132200000578-3301094-The_search_scene_has_been_expanded_to_more_than_20_miles_as_ team-a-11_1446563225430.jpg


http://i.dailymail.co.uk/i/pix/2015/11/03/15/2E0F5DD600000578-3301094-The_investigators_have_identified_12_separate_debris_fields_ prov-a-27_1446563401024.jpg

http://i.dailymail.co.uk/i/pix/2015/11/03/15/2E0FF5FD00000578-3301094-Metrojet_claimed_their_aircraft_was_in_very_good_condition_o n_th-a-30_1446563428762.jpg

[Sawbones]

The translated article that Kulverstukus provided, and commented on by Air Scotia is difficult to accept in its entirety, but after numerous reads I feel there may well be some validity to it.

It brings to question the safety culture within this airline. Issues such as training bonds, defect reporting, inexperienced cabin crew, all driven by an extreme low-cost, possibly almost bankrupt airline are certainly ingredients not to be overlooked by accident investigators.

[Ian W]

Have we discounted the Russian pathologists reports that some bodies seated in the rear of the plane suffered injuries consistent with an explosion?

(For some reason, searching the thread doesn't throw up any results for this).

An aircraft at 30.000ft pressurized to 8000ft breaks up and the fuselage tumbles the pax strapped into their seats near the fuselage break first suffer an explosive decompression then have debris from the more complete part of the fuselage ejected past them and into them as it is sucked into the 400kt airflow. Then the tumbling airframe leads to the open part of the fuselage intermittently facing into the 400kt air flow. I put it to you that the effects and injuries would be expected to look like being next to an explosion.

[WNTT]

http://i.dailymail.co.uk/i/pix/2015/11/03/15/2E10E5F500000578-3301094-image-a-64_1446566217200.jpg

this one caught my eye, is this the roof rear of the wings?

[Smott999]

Is the aft bulk cargo door still attached? I know we see the two R exit doors w the empennage, but wondered about bulk cargo.


Could the tail strike have relation to a poorly fitting aft bulk cargo door given its location on the 321?

Could failure of that particular door cause what we've seen?

[Kulverstukas]

Ian W, there was clearly stated that last rows paxes bodies bears severe burn marks (up to 90% of skin, scorched clothes etc.).

Bear in mind through that it's not direct words but some journalist's interpretation.

[flash8]

Breaking Leak from Egyptian source - engine blast. (via Al-Masry Al-Youm)

Like all the other 'breaking' news from the Egyptians best left completely ignored. My worry is that they'll hinder the investigation rather than assist.

[oleostrut]

Door seals are a maintenance item. Could just be a timing coincidence. They would not have re-worked the door openings for a tailstrike. Plus, several references indicate Airbus did the tailstrike repair.

Also, doors are adjustable, and do require some attention from time to time.

[flightbris]

[oleostrut]

Flutter does come to mind.

[andrasz]

The "negative" G forces ... must have been incredible
There is a telling photo above (the 3rd, showing the engine). The Engine pylon is bent upwards. That component is strong enough to support half the weight of the plane without deformation if a landing gear fails, a good 45 tons. Engine weighs roughly 2 tons. Rest is maths...
Same forces have shorn off the fan. The only good bit is those over and in front of the wing (including the cockpit crew) never knew what hit them.

[peekay4]

I stopped reading when the author claimed to use WAAS in Australia in 2011
And the difference between GPS Altitude and Baro Altitude is a red herring anyway, because what we mostly care about here are the altitude changes, not the absolute altitude value be it GPS or Baro.

Which is why the experiment RYFQB did (see chart (http://www.pprune.org/rumours-news/569907-breaking-news-airliner-missing-within-egyptian-fir-41.html#post9168426) a few pages back) was neat because it showed that altitude changes computed based on the FR24 GPS vertical speed matched very closely with the recorded pressure altitude changes.

So even though the FR24 pressure altitudes are unreliable past a certain point, we can reconstruct corrected altitudes with some confidence by using the computed GPS data (which obviously is not affected by pressure data errors).

[timgill]

More than 900 posts on this thread, and I have read and tried to understand every one of them.

I would like to nominate Kulverstukas as the singular contributor who has made the most sense of this terrible affair.

[barit1]

For Double Back:

A similar accident - Lockheed Lodestar runaway trim in cruise, resulting negative G load failed the wing spar. The NTSB report is around somewhere, but here's a summary: ASN Aircraft accident Lockheed 18-56-24 Lodestar N1000F Lake Milton, OH (http://aviation-safety.net/database/record.php?id=19620904-0)

[ChicoG]

A similar accident?

For Double Back:

A similar accident - Lockheed Lodestar runaway trim in cruise, resulting negative G load failed the wing spar.

The wing fell off.

[A0283]

Sinai crash: Russia extends search area and uses drones - BBC News (http://www.bbc.com/news/world-middle-east-34719307)

[WNTT]

[A0283]

Former FAA official: 'Clash of cultures' in crash probe - BBC News (http://www.bbc.com/news/world-us-canada-34717356)

I find it a bit early to talk about culture clashes. Just like in the investigations themselves, let's get as many facts as possible first.

A number of actions of the Egyptians can only be applauded. We have not seen any images of victims. And passenger luggage has been collected and guarded. Quite a difference from MH17 for instance. Next to that you can only have respect for the (especially the first) people on the ground being confronted with it all. From the ordinary soldier to the investigators and supporting teams.

[A0283]

Sinai crash: Russia extends search area and uses drones - BBC News (http://www.bbc.com/news/world-middle-east-34719573)

Isn't this the first recorded (flying) drone use during the investigation of a large commercial airliner accident?

[Kulverstukas]

A0283 with all my respect for your contribution, first link is cut version of LifeNews video (http://www.pprune.org/rumours-news/569907-breaking-news-airliner-missing-within-egyptian-fir-47.html#post9168901) from Nov, 2th and second one is another example of "only we western people newer lie and are God sent angels at the Earth".

To all other participants - can we concentrate on technical part of investigation and stop speculate about evil Putin's slaves and mendacious Egyptians? There is whole Jet Blast forum for it.

[WeeJeem]

Nope, a Bluefin-21 was deployed in the search for MH370 last year.

[lomapaseo]

here is a telling photo above (the 3rd, showing the engine). The Engine pylon is bent upwards. That component is strong enough to support half the weight of the plane without deformation if a landing gear fails, a good 45 tons. Engine weighs roughly 2 tons. Rest is maths...
Same forces have shorn off the fan

The part that is bent upwards is the soft part of the pylon ahead of the wing. The beefy structure is way behind it.

probably this bent when the engine hit tailpipe first at an impact angle. Anything going on with rotating fan loading reacts out in the bearing supports and not the pylon. (no math was used :E)

[Leightman 957]

I find it odd that the discovery of the HS pieces (I still haven't seen pics of both) has been met with quick general prune agreement that they failed in direct shear due to aerodynamic forces from tumbling at speed....while at the same time no one disputes a nose down rotation, negative G tuck by the fuselage minus tail at the very same airspeed, where the wings very apparently did NOT fold up....AND that forces on the wings were sufficient to strip of both engines off the wings. Why did the wings remain intact spanwise?

Also, if the HS pieces failed cleanly in shear, does that mean the center HS box section remained in place? Pics of that assembly would be nice.

[A0283]

Leightman uptill now I have not seen pictures with the other half or the central box structure of the THS. Rudder still missing too. So of course too early to have any clear conclusions ... just a longlist of preliminary possible scenario's ...

Perhaps the rudder, and especially where it is found, will turn out to be more important in the end. So hope it is found by the ongoing search and hi res pictures published.

Wing in one part is indeed striking. Perhaps not the center wing box and large inner parts of the winghalves staying together, but not losing substantial parts of the outer winghalves. Maybe part of the reason is that the engines came clean off before a structural limit on the wings was exceeded. You also wonder, that if the plane rotated, that it rotated in a manner and at a rate which generated relatively low dynamic loads. While (not a judgement at all, just trying to indicate different interests) 'flying only' pilots (not engineering pilots) often state that discussion on issues like these are not 'for them', it is challenging from an engineering point of view.

Important for elimination of scenario's is where and when the rudder, THS and engines broke off, and in what order. So the more we have on these items the better.

[Kulverstukas]

The plane's voice recorder was damaged in the crash, preventing it from being analysed,

Doesn't looks so

http://i.dailymail.co.uk/i/pix/2015/11/02/17/2E0B405F00000578-3299886-image-a-2_1446486470370.jpg

http://i.dailymail.co.uk/i/pix/2015/11/03/15/2E11EA1800000578-3301094-image-a-62_1446565911853.jpg

[Kulverstukas]

Perhaps the rudder, and especially where it is found, will turn out to be more important in the end.

In what I'm aware of, all major parts of plane was found, so I think that VS and HS parts are not missing, we just doesn't have photos of them.

[AirScotia]

Kulverstukas, is your photo of the FDR or the CVR?

Is this (http://www.theguardian.com/world/2015/oct/31/russian-plane-crash-investigators-seek-cause-of-a321-crash#img-2)a picture of the other recorder?

[A0283]

For me "missing" = "evidence (validated pictures or validated statements) not available in the public domain".

We are not in a position to have any idea what the searchers and investigators have found.

A "validated picture"= Picture that helps to identify a part with more than say 90% certainty. Which means you generally need good ones, more than one, and preferably context and geographic position.

Example is the APU itself. A number of posters expect that it is in the tailcone. But I have not seen a picture of the inside of the cone and no picture of the APU unit. So, APU not validated. Same with the nose landinggear.

A "validated statement" = official statement by more than one investigation party or official spokes person supported by as much as possible pilot, engineering, manufacturing and operations information and experience.

[Machinbird]

For the last day, some of the reports coming out near the investigation appear to be from La La land.
I certainly hope that the "fix" is not in and that we will hear an objective and logical analysis of the accident that will encompass all the observed data. :suspect:

[Kulverstukas]

AirScotia it's clearly reads "solid state cockpit voice recorder". And at your photo it's definitely other recorder, as it has completely different layout.

[Kulverstukas]

@Kulver - definition of missing

Awww, I get it. Agreed, its more challenging for armchair detectives to make right conclusion before official team and with limited access to evidence. But not impossible, At least RedWings rwy excursion case was solved in forums long before even preliminary official report was published.

[AirScotia]

@Kulverstukas - you're right. If I squint I can see. The CVR does not look badly damaged - certainly less so than the FDR.

I'm wondering where the recorders are being analysed, and to repeat my earlier question - how good are the Egyptian resources for doing this?

[anartificialhorizon]

Surely, in the history of modern aviation (i am talking the jet age using vacuum loos), would this event not have replicated many times? Not just on aircraft, but anywhere human waste is collected? That theory is a non starter imho.

Regarding the bomb theory. If there is a rogue baggage handler, cabin cleaner, ground ops person etc. at Sharm (or where the aircraft originated), would you not keep quiet? The opportunity still exists to do it again? The fact that it is a Russian airliner also adds weight to that theory, in that Russia have only recently started to fight IS in Syria.

I think we are down to 2 theories. A fuel tank explosion, which rare, is not unprecendeted in modern jets, or a bomb, either planted prior or carried onboard. Remember, the passengers were not 100% Russian.....

Both theories would lend themselves to the flash seen by the US satellite. The tail coming off (again imho) would not have caused a flash.

[dsc810]

Well
The Egyptians will be desperate for it to be anything but a bomb as if it were it would truly screw over their tourist industry.

The French/German/USA will be desperate for it to be a bomb so it can be blamed on 'terrorism' (that's freedom-fighters if you are on the other side) and that the aircraft is 100% OK.

The Russians will be in a quandry.
1. if it was a bomb then they would be forced into some retaliatory action which they probably do not want to get involved in for all sorts or reasons.
2. If it was crew or technical failure then that is not much better as it was their crews and their airlines operating it.
So on balance the Russians would probably hope it is some undetected and undetectable technical issue with the aircraft or engines.

[Karel_x]

I am nearly sure that data from both recorders are readable. Containers with memory modules are in good state. It may not be readable through local interface, but solid state memory modules probably will not be damaged.

[edmundronald]

Since 9/11 we are seeing billions invested in security theater, and at the same time every half-assed businessman operating out of a shed in some third world country is allowed to ferry passengers in airliners.

Rather than all the baroque theories of malfeasance, is someone actually looking at simple structural failure through too many cycles, allowed by insufficient inspections? That Airbus was 18 years old, enough for a mediocre maintenance régime and a few undeclared hard knocks to take their toll.

Edmund

[peekay4]

A fuel tank explosion, which rare, is not unprecendeted in modern jets

A fuel tank explosion might be the effect, not the cause.

E.g., an uncontained engine failure might lead a chain of events and subsequent rupture of a tank, either through direct piercing or through structural breakup, causing an explosion.

[andrasz]

Please, at least let's try to quote correctly. BBC says:

"All flights due to leave the holiday resort for Britain this evening have been delayed to allow a team of UK experts to assess security"

NOT suspended.
(Sharm el-Sheikh flights to UK delayed amid bomb fears - BBC News (http://www.bbc.com/news/uk-34724604))

[andrasz]

is someone actually looking at simple structural failure through too many cycles


I'm sure the airbus 'advisors' are doing exactly that, with some anxiety.

[sky9]

Cabinet Office Briefing Room
“The Prime Minister called President Sisi yesterday evening to discuss what measures the Egyptians are taking to ensure the tightest possible security arrangements at Sharm el-Sheikh airport.

“While the investigation is still ongoing we cannot say categorically why the Russian jet crashed. But as more information has come to light we have become concerned that the plane may well have been brought down by an explosive device.

“In light of this and as a precautionary measure we have decided that flights due to leave Sharm for the UK this evening will be delayed. That will allow time for a team of UK aviation experts, currently travelling to Sharm, to make an assessment of the security arrangements in place at the airport and to identify whether any further action is required. We expect this assessment to be completed tonight.

“In terms of flights from the UK to Sharm, there are no more departures today.

“We would underline that this is a precautionary step and we are working closely with the airlines on this approach. The Prime Minister will chair a COBR at 18.45 to review the situation and we will provide an update after that meeting.

“We recognise that this information may cause concern for those in Sharm and indeed for those planning to travel to Sharm in the coming days. We have deployed extra consular staff to Sharm who will be on hand at the airport, working with the airlines, to assist British holidaymakers there. For others, either in resorts at Sharm or planning a holiday to Sharm in the coming days, our advice is to contact your airline or tour operator.”

“At this stage we are not changing the level of our Travel Advice.”

[macdo]

This is the worst possible news for airlines, Egypt and probably the world. Having operated out of SSH and visited as a tourist, a security breach (if there has been one) is hardly surprising.

[Self Loading Freight]

I wonder if someone popped down to SSH and gave the security system there an eyeball, then reported back that all was not - for want of a better word - kosher. And who knows what other signals have come out of what would certainly have been a sudden and intensive look at intelligence gathered over recent days. Not every investigator working on this crash will have been pounding dust in the desert.

[Newton123]

Came across this old report from 2004:


SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD)
for certain Airbus Model A319, A320, and A321 series airplanes. This
proposed AD would require modification of certain auxiliary power unit
(APU) alternating current (AC) generators. This proposed AD is prompted
by a report of an explosion in the APU compartment, which blew open the
compartment doors. We are proposing this AD to prevent oil vapor
leakage from the APU AC generator, which, when combined with an
electric arc at the electrical receptacle, could result in a fire or
explosion in the APU compartment during flight.

Federal Register, Volume 69 Issue 194 (Thursday, October 7, 2004) (http://www.gpo.gov/fdsys/pkg/FR-2004-10-07/html/04-22565.htm)

No idea if any relevance - just thought I'd put it out here for the experts to comment on.

[fincastle84]

I totally agree with SLF. Surely this is a case of the government being ultra cautious & who knows what information may have been passed to Whitehall. Better to be safe than sorry.

[jmmoric]

One thing I noted from the beginning of the thread, which I think is ruled out.

Someone mentioned the ISIS would try to shoot down a Russian jet, with the argument Russia is now involved in Syria. Some then mentioned that would be unlikely, since ISIS would be unable to see who they were shooting at.

Are anyone aware that wrongdoers could very well be using the same tool we use everyday in following flights? Give the FlightRadar24 or another equivalent, and they'll have all the information they need to identify overflights.

Giving the generel public acces to data, previously keept for ATC, could very well be creating a sideeffect of not being able to "protect" flights.....

Sorry for the detour, but think about it, now back to the sad accident.

[NorthernChappie]

If this does prove to be a terrorist act, could the target have been any aircraft leaving Sharm and the one on which a device was plant just happened to be Russian? Thought about this since Saturday and if it was a response to Russian involvement in Syria, it doesn't allow much time to get a device in place from scratch. I wonder if this has been in planning for considerably longer?

[Karel_x]

The Russians will be in a quandry.
1. if it was a bomb then they would be forced into some retaliatory action which they probably do not want to get involved in for all sorts or reasons.
2. If it was crew or technical failure then that is not much better as it was their crews and their airlines operating it.
So on balance the Russians would probably hope it is some undetected and undetectable technical issue with the aircraft or engines.
I don´t think so.
1. I think that Putin´s words that "any attempt to intimidate Russia will fail and they will continue to fight with terrorism in Syria and anywhere" are clear enough. Also increase of fight activity in Syria right after disaster is visible.
2. MetroJet probably will finish operaton soon because of Rosaviacia measures. The same as most of companies after fatal disaster in Russia. And don´t forget, Metrojet is Russian company only "de iure".

[Lone_Ranger]

The Russians will be in a quandry.
1. if it was a bomb then they would be forced into some retaliatory action which they probably do not want to get involved in for all sorts or reasons.

If it was a Bomb and they find out who was responsible, I honestly don't see The Russkies being shy about retaliating.

Perhaps you Can state these Reasons why Russia would be averse to action, dsc810?

AAh I see, only I can see my posts...do you get off on this pathetic childishness?

[Sober Lark]

Kulverstukas, I wonder how 'engine blast' became 'explosive device' by No 10. Politics.


In passing you mentioned Head of Investigation committee of RF flew back home from Cairo today without chances to visit crash site - yesterday he was not allowed because paperwork was not done and today because of severe weather at site


Do you happen to know when the drone took the aerial views of the crash site?


Thank you Pontius, I spotted that and quickly deleted it.

[videoguy]

Could this break-up be thrust reversal related? (Lauda Air Flight 004, 26 May 1991)

Some Russian and/or Soviet era aircraft are able to reverse thrust in flight. Did pilot had previous experience in flaying Russian aircraft and deployed reversal by mistake?

[Kulverstukas]

Karel_x,
1) You're right, since first big terror act RF policy is "we doesn't trade with terrorist".
2) Kolavia/Metrojet/Brisco holding is owned by Russian (Chechen if it is of importance) and Turkish citizens 50/50.

[Sergey Tachenov]

Really. You think because the aircraft was still climbing the belt sign must have been on, therefore all pax were seated?

Amazing.

Are you a pilot? Do you fly as a passenger very much?

The belt sign in many airlines comes off after transition (FL100-FL150) if in smooth air and nothing visible ahead that poses a turbulence threat.

Depends on the airline, I guess. I used to fly with Transaero last years, and they never switched it off until reaching the designated FL. But then again, Transaero was the safest Russian airline, so I have no idea about those small companies...


The Russians will be in a quandry.
1. if it was a bomb then they would be forced into some retaliatory action which they probably do not want to get involved in for all sorts or reasons.

Er... do you know we have already went into some intensified anti-terrorist action in Syria, and now Putin has a hard time convincing people it has nothing to do with the crash?

[Kulverstukas]

Putin has a hard time convincing people it has nothing to do with the crash

Really? Can you give me direct proof about that?

[Kulverstukas]

Kulverstukas, I wonder how 'engine blast' became 'explosive device' by No 10. Politics.



Sorry, don't get it?

Do you happen to know when the drone took the aerial views of the crash site?

This video at LifeNews site is November, 2nd

[Prada]

At least half of the tail structure looks intact. Lower half... who knows. may be flattened by impact with ground, maybe destroyed in HS separation event.
http://www.keri.ee/crash/tail_back.jpg

[L8 Fr8]

What would be the result if the pin that goes here either came out or failed, or the actuator that attatched to this broke/failed.

http://i300.photobucket.com/albums/nn25/bubbarosa/Airbus-Houmlhenruder_zpsz00dtlie.jpg

[Sergey Tachenov]

Really? Can you give me direct proof about that?

It's in the Russian news:

TASS: Russian Politics & Diplomacy - Kremlin warns against linking A321 crash in Egypt with Russia?s operation in Syria (http://tass.ru/en/politics/833709)

But I have certainly exaggerated it by saying "having a hard time".

[oldoberon]

At least half of the tail structure looks intact. Lower half... who knows. may be flattened by impact with ground, maybe destroyed in HS separation event.
http://www.keri.ee/crash/tail_back.jpg

anyone know where the original is from, trying to get a higher res or bigger version of it

[Kulverstukas]

Sergey, moreover, ""Hypothetic insinuations on that score are inappropriate. Besides, these are absolutely different issues. There is no point in linking them," Peskov said, when asked if progress in Russia’s operation in Syria might be affected if it was confirmed the plane had fallen victim to a terrorist attack."

As I said, message is clear: We doesn't make trades with terrorists.

[AndyJS]

The British government has decided to halt flights from Sharm el-Sheikh:

Quote:

"While the investigation is still ongoing we cannot say categorically why the Russian jet crashed. But as more information has come to light we have become concerned that the plane may well have been brought down by an explosive device."

https://www.gov.uk/government/news/sinai-plane-crash-uk-flights-from-sharm-el-sheikh

[Sprinkles]

As someone who is due to operate a Sharm this weekend I have to admit I've been seriously worried these past few days. I've been saying for months (not on here) that the next place, after Tunisia to receive this treatment would be Sharm. It took six weeks for our company to circulate the NOTAM regarding St Catherine which I found far from ideal. I operated a number of SSH flights during this six week period, one of which took me straight over CAT below 25,000' because 22R was in use. My eyes are on stalks every time I go near the place and brief the other guy if I see anything untoward I'll be taking evasive action.

IF, and it's a big IF this tragedy is sinister, why can't we just get the RAF down there with their bomb dog squad and go through everything checked in, and the aircraft prior to departure? To me it's the only way we can reduce a bomb threat to its lowest acceptable level. The Dogs won't lie and identify anyone, or item of baggage that'll be suspicious.

[Gary Brown]

Just sticking for a moment with the earlier Egyptian statement talking about an "engine explosion", is there anything in the photos so far of the engines themselves - or adjacent fuselage - that would support that (appreciating that, whatever the cause, those engines fell far, fast and hard and have huge final impact damage)?

I recall many messages ago someone looking at a photo of one of the engines and saying something about missing fan parts. But I now can't find that post.

[Kulverstukas]

http://cdn.aviaforum.ru/images/2015/11/720220_a1d247ad42b0433e3bc64e536f5defaa.jpg

http://img.gazeta.ru/files3/701/7866701/upload-TASS_13105574-pic668-668x444-68089.jpg

http://cdn.aviaforum.ru/images/2015/11/720260_19d94ef761d338430ddd24a18c13468e.jpg

http://cdn.aviaforum.ru/images/2015/11/720261_9d54645925577964309bbdce40452777.jpg

http://www.dw.com/image/0,,18820109_403,00.jpg

[rog747]

Sprinkles
quote ''As someone who is due to operate a Sharm this weekend I have to admit I've been seriously worried these past few days. I've been saying for months (not on here) that the next place, after Tunisia to receive this treatment would be Sharm. It took six weeks for our company to circulate the NOTAM regarding St Catherine which I found far from ideal. I operated a number of SSH flights during this six week period, one of which took me straight over CAT below 25,000' because 22R was in use. My eyes are on stalks every time I go near the place and brief the other guy if I see anything untoward I'll be taking evasive action.

IF, and it's a big IF this tragedy is sinister, why can't we just get the RAF down there with their bomb dog squad and go through everything checked in, and the aircraft prior to departure? To me it's the only way we can reduce a bomb threat to its lowest acceptable level. The Dogs won't lie and identify anyone, or item of baggage that'll be suspicious

i'm amazed that descents were allowed too - my pal a 757 skip out of BRS
had the same - he's ex RAF and did not like it one bit



indeed - trouble is the Metrojet had been on the ground for 12 hours so this occasion any bomb could have been placed on board not in baggage but by an airport worker in the pay of dirty others

[AndyJS]

Is security known to be lax at Sharm el-Sheikh?

[G-CPTN]

According the BBC's aviation expert, UK crews operating into Sharm are 'at the limit of their hours', so delays for departures from Sharm are likely to result in cancellations, or stops in Europe for replacement crews.

[Kulverstukas]

Another engine?

http://www.youtube.com/watch?v=6Vnd3gQPPqE;t=144

[A0283]

Dont know if you mean one of my 'update' posts ...

Found pictures of 2 different engines. I call them A and B as i have no been able to link them to either left or right wing positions yet.

Found pictures of 2 different fans. The first still has all blades (or 1 is missing) and all visible blades are complete end to end. The second clearly has a number of broken blades.
One of the spinners is clearly sooted (would have to check which one), while the engine itself is away from a 'burned area'. So a preliminary impression is that there was a fire at some stage inside the engine. Not possible to say of course if this was during the flight, during the descent or after the engine hit the ground. There is no clear evidence of fire at the outside of the engines. And no trace of 'shrapnel' damage. The leading edge of the cowlings and the cowling doors have separated but are close to the engines (as far as i can see now).

Hope this answers part of your question.

[L8 Fr8]

"Russian media outlet LifeNews claims that more than 200 fragments of human remains from approximately 150 people have arrived in St Petersburg.
According to sources, there was a significant difference in the cause of death between passengers at the front and the rear of the aircraft.
Those at the front suffered 'blunt force trauma of the chest, abdomen and pelvis with multiple fractures of upper and lower limbs with tears to the internal organs. Deaths occurred due to acute blood loss, shock and open head injuries.'
Those at the rear of aircraft suffered 'explosive trauma with multiple burns over 90 per cent of their soft tissues'.
Passengers at the back had shrapnel injuries and were peppered with metal particles."

Russian plane crash reveals ?no proof it broke up in mid-air', Egypt claims | Daily Mail Online (http://www.dailymail.co.uk/news/article-3301094/Terrifying-final-moments-doomed-Russian-jet-Plane-lurched-passengers-sucked-seats-external-impact-blew-jet-apart-flight-data-reveals.html)

[Gary Brown]

Kulverstukas - thanks for those engine pics. Without context, it's difficult to say. But a guess would be that the fan assembly is lying somewhat near the engine (maybe...) and has separated from it on final impact?

And AO283, thanks too. My impression is that nothing in the photos is screaming out major engine failure but of course photos can be deceptive and imcomplete (as well as me being no expert in the engineering of all this!).

[henra]

Those were frightenly high frequency phugoids, on the order of 8 seconds bottom to top.



Very good Observation!
Even GA aircraft usually have phugoides around 20s. Airliners typically 40 - 60s. 8s is a clear indications something is totally wrong. You would get a high frequency phugoide if the angle of incidence is very different between wing and tailplane. Which would fit quite well to the assumption that the HS must have experienced a significant excursion.

[RTM Boy]

The more photographic evidence I see, the more and more it looks like a heat/flash event occurred at altitude and certainly before wreckage hit the ground.

Whatever the exact cause and sequence of events, this must surely exclude simple mechanical, structural and crew-related actions as the cause because they would simply have not resulted in a fire event.

It would be hasty and unwise to read too much into the suspension of UK airline flights from SSH and an imminent COBRA meeting, but it would not be unreasonable to conclude that those in authority now have information (that we don't have) that gives them a good reason to be cautious.

[Gary Brown]

Kulverstukas and A0283:

Although the engine in the still above and the one in the video look different to me (though it's not easy to be sure), I think that the fan assembly in the still is the same fan assembly shown at about 2.17 in the video, but from a different angle. Or are we looking at 2 separate fan assemblies do you think?

[L8 Fr8]

Stop Kulverstukas video Post 923 at 2:23 full screen. Look at the top right of what appears to be the turbine section of this engine. Is that a big hole? Turbine disintegration maybe?

[A0283]

@AGBagb My impression is that nothing in the photos is screaming out major engine failure but of course photos can be deceptive and incomplete...

First impression is indeed 'no screams'. But it would help if we had more pictures. Especially one top down, and of course turning the engine over. With the present pictures you cannot see anything of the HP turbine and the aft end of the engine. It may be buried, but it appears to be a rocky ground with little rock and little sand or grit expelled backwards, and the fan and LP area appears to be crushed and not dug in. If they overturn the engine you would get a better answer.

The 'supposed' engine failure would have to be catastrophic, which means fast, and causing extensive damage to the engine ... and probably significant damage to the wing too. At this stage the pictures do not point in that direction. The wing halves look pretty complete. The cowling components are found close to the engine. Very prelim of course to say that, but still ...

[Drive4it]

Not flew out of Sharm but last year we flew out of Hurghada (as SLF). Security checks on UK pax airlines were more thorough than Russian airlines, with one more additional check before boarding. Saying that it was a Friday (prove me wrong but the height of religious week)so there did seem to be lots of free flowing staff around without door security codes etc to be conducting their prayers.

[RTM Boy]

Yes, if there was a small bomb the initial detonation would probably not be picked up even by an IR satellite, but the fireball that follows would be, even for a smallish device, especially because it would have occurred when the sun was only just rising so the 'background' would have been relatively cool.

Also, if any device was placed adjacent to say the central fuel tank the chain reaction would, probably within milliseconds, lead to a very visible heat flash.

[UAV689]

Where Next? Morocco? That also has got to be a big weak spot for European flyers.

[RTM Boy]

In the same way that a burglar can get in anywhere if they are determined and skilled enough, likewise you can never totally secure an airport, or a plane. It's a matter of degree of risk, the number of layers of security and degrees of trust.

In the extreme, quis custodiet ipsos custodes?

Channel 4 News is right now strongly suggesting the bomb-on-board theory. ITN is not known for jumping the gun.

[comcomtech]

I arrived there about 12 hours after the crash. Passengers exited the aircraft onto the tarmac and are driven in buses to a large hallway. They are observed by only one guard. At the time, it occurred to me that security is less than air tight.

[Sokol]

One of the spinners is clearly sooted (would have to check which one), while the engine itself is away from a 'burned area'.a lot of Black Sand around this Fan, so probably burnt after it hit the ground. (A very untypical burnmark for inflight tough.)

An to answer your question about burning inflight: It does burn inflight at a certain Area. Thats the principle...

Stop Kulverstukas video Post 923 at 2:23 full screen. Look at the top right of what appears to be the turbine section of this engine. Is that a big hole? Turbine disintegration maybe?Its definitely not the turbine department. Even if, the hole wouldnt be shaped like this after turbine separation.

What we can see ist that the Blades overall are in pretty good shape. Which leads to nearly only two possible Conclusions:
1: Magic.
2: Turbines stopped working in Air, which means Fuel was out(possibly in combination with friction), which possibly means that the Engines separated from the body at an early stage of the event.

[skridlov]

Current position and wording of assessment after the COBRA meeting today would seem to indicate that UK has confirmed suspicions of a bomb although they aren't going to pre-empt the official investigation.

[Kulverstukas]

Dear colleague armchair detectives!

Can I summarize what we know so far and make brief description of events?

1) Plane was in relatively good condition and maintained adequately at least.
2) Crew is experienced and rested
3) No suspicious passengers onboard, no major delay or any other inconvenience through ground ops reported
4) T/O without issues and begin climbing OK
5) When reached about intended FL but before leveling something very brief (fraction of seconds) and violent happened INSIDE, plane was broken in parts and falls down.
5.1) This event was so short that crew have no time to complete any action, so it's not stall or similar.
5.2) This even was followed (and possible is cause) of tail section detachment
5.3) Part of this event or it's direct result was intense fire (close to explosion) which destroyed wings section and killed last rows paxes

Now some speculations.

1) Place of event is somewhere middle to tail part of plane, between front cargo door and RPB.
2) I think also that it was below or at the level of cabin floor

...

[Back at NH]

Lot of use of the words "may have been", flights delayed not cancelled and the travel advice for Sharm not changed.

[up_down_n_out]

"message is clear: We doesn't make trades with terrorists".

Message is as clear as :mad: mud.
It didn't stop someone blowing themselves up in DME or any part of the capital at any time, or downing TU154 in the past.

I'd bank a nice fat bet, it was a bomb, bearing in mind the "star wars" mentality, Putin's birthday firework night, and propaganda showering Russian state TV currently. :rolleyes:

[RTM Boy]

Ireland has suspended flights to/from SSH also

[StuntPilot]

Kulverstukas:
You've got the facts straight but, although I agree that the cause can certainly be INSIDE, I think we can't fully exclude structural causes followed by fire (causing passenger injuries etc.) completely yet. If you think we can I'd appreciate to hear your reasoning. We know many results of what happened but lack the sequence of events and therefore certainly do not know the start of it yet. The key piece of the puzzle is still missing...

Please keep up the good work!
I think we're getting close to having enough facts to draw harder conclusions.

[Prada]

yes Kulvertukas, having been watching pictures and reading for hours and hours bulkhead failure could not cause such events we already know, and I suspect that RPB is still in place.
There is a very large piece of right side fuselage which suggests that left aft side is in much smaller pieces, caused by initial destructive event on the left. Probably close to fuel tank. At least somehow pulverized and flying fuel had to get into passengers cabin. Left HS could have been ripped off by fuselage pieces that dislodged the whole HS structure during which tailcone was separated.
Meanwhile leaking fuel mixed with air burned passengers. :( That phase couldn't last very long as aerodynamic forces ripped tail completely off....

Thats just a speculation based on limited evidence we have.

[Sir George Cayley]

Outbound delay suggest our Guardian Forces are not happy with Egyptian Guardian Forces. So once the cabins have been cleaned, home to Blighty.

The outbound ban seems less clear unless it's to send a message to people in the region that Newton's Law applies;

"To every action there is an equal and opposite reaction"

Doesn't it eh Vlad?

SGC

[Infieldg]

anyone know where the original is from, trying to get a higher res or bigger version of itGoogle image search finds all matching images if you give it the url of an existing pic or upload one.

Right-click on this pic and choose properties and copy the filename (http://www.keri.ee/crash/tail_back.jpg) OR right-click and select 'save picture as' or 'save image' depending on your browser.

Go to Google Images (http://images.google.com), click the little black camera icon at the right end of the search bar and EITHER paste the url or click 'Upload image' and upload the copy you saved and it'll find all copies, in this case 59 sites, none large though sadly. Click here to see them - Google (http://tinyurl.com/pgojm2d)

Cool or what :) The URL it generates is huge but you can shorten it at tinyurl.com.

[Magellan]

Thomas Cook Holidays seem sanguine enough, it being a travel company run by some of the most expert aviation security folks in the known world. A sleep-filled night tonight for its Gatwick and Manchester pax departing tomorrow, no doubt:

https://www.thomascook.com/travel-updates/

[RTM Boy]

Dutch authorities have also suspended flight to/from SSH until at least Sunday. It is reported that the they will wait to see the findings of British investigation into security at SSH.

[Kulverstukas]

I think we can't fully exclude structural causes

I don't name this event just because structural failure still not ruled off. On the other hand, I can't remember any similar case of almost immediate destruction of civil a/c in air at FL because of structural failure.

caused by initial destructive event on the left

Dear Prada, can you illustrate this conclusion? I'm not so familiar with A321 parts so for me it's difficult to locate debris pieces to complete picture.

[thf]

Source from Egypt (http://www.reuters.com/article/2015/11/04/us-egypt-crash-cause-idUSKCN0ST2HJ20151104):

The cause of a Russian plane crash in Egypt is looking more like an explosion but it is not clear whether it was linked to a fuel or engine trouble or a bomb, an Egyptian source close to the investigation said on Wednesday.

(...) "It is believed to be an explosion but what kind is not clear. There is an examination of the sand at the crash site to try and determine if it was a bomb," the source, who is close to the team investigating the black boxes, told Reuters.

"There are forensic investigations under way at the crash site. That will help determine the cause, to see if traces of explosives are found."

Source from Russia (http://www.reuters.com/article/2015/11/04/us-egypt-crash-cause-russian-aviation-idUSKCN0ST2OX20151104):

An investigation into the crash of a Russian plane in Egypt last Saturday is looking into the possibility of an object stowed on board causing the disaster, a Russian aviation source said on Wednesday.

"There are two versions now under consideration: something stowed inside (the plane) and a technical fault. But the airplane could not just break apart in the air – there should be some action. A rocket is unlikely as there are no signs of that," the source said.

[henra]

I find it odd that the discovery of the HS pieces (I still haven't seen pics of both) has been met with quick general prune agreement that they failed in direct shear due to aerodynamic forces from tumbling at Speed


I doubt that once separated from the rest of the fuselage forces would be sufficient to shed the feathers. The tail assembly is very strong and the mass of that section behind the RPB is not very big. Moreover I don't see why that section should 'tumble' when separated. It is basically a dart and would probably stabilize quickly.
IMHO that shearing of the HS would only happen as long as it was still attached to the fuselage.


....while at the same time no one disputes a nose down rotation, negative G tuck by the fuselage minus tail at the very same airspeed, where the wings very apparently did NOT fold up....AND that forces on the wings were sufficient to strip of both engines off the wings. Why did the wings remain intact spanwise?
Relevant question!

So, let's have a look at it:
The Event started at ~250kts IAS but according to the FR24 data Speed dropped quickly to below 200kts. I don't know the exact max cl of the A321 wing in negative directions, but 1g stall Speed of the inverted wing should be somewehere around 150 - 160kts min. I don't know the max negative g the A321 wing will take but let's assume 2,5g. That would mean ít would reach its lift limit at 240 - 250kts. In other words: at the speeds we are talking about it is entirely conceivable that the wings didn't shear off even in case of a bunt over pretty quickly after the initiating Event.

So a possible Scenario remains: Something caused a rapid and massive excursion of the THS/Elevator. This causes the HS to fail. Aircraft starts to bunt over putting enormous load on the VS and rear fuselage, causing the fueslage directly aft of the CWB to collapse.
Possibly the otherwise historically almost undestructible VS hits parts of the fuselage/structure in this disintegration process. and fuel lines to the Center tank being severed (/the Auxiliary Center tank disintegrating -did this one have one installed?) releasing fuel into the open tube of the rear fuselage - being ignited by sparks from severed electrical lines.

Not saying this was the case, just it still appears to remain a conceivable Scenario within the limited Facts we have so far.

[Chronus]

I would have thought time to call it a day on which bit came off when and how and why and what was turning and when it stopped and why. Could there now be much doubt and speculation left as to how this aircraft fell out of a clear blue sky.

No government takes a decision to suspend flights to such a popular destination lightly. There must be more than good reason for such a decision. The first admission of responsibility by ISIS was not accepted by Egypt, now after the second one and with more evidence having been examined by those in the know, how could the threat be ignored. The target must have been the Egyptian economy and its government. Naturally they wish to protect it. Our government must protect the lives of our citizens. In suspending all flights they have done precisely that.

I don`t know how many tourists of many different nationalities may be stuck there currently, but it sure looks a tough one to get them out of there quickly and bring them home safely. It looks like a busy week ahead to juggle all schedules in some semblance of order.

I wait to hear the outcome of the Cobra meeting, under way now.

[frankpgh]

CNN)[Breaking news alert, posted at 3:08 p.m. ET Wednesday]

The latest U.S. intelligence suggests that the crash of Metrojet Flight 9268 was most likely caused by a bomb on the plane planted by ISIS or an ISIS affiliate, according to a U.S. official familiar with the matter. The official stressed that there has not been a formal conclusion reached by the U.S. intelligence community. "There is a definite feeling it was an explosive device planted in luggage or somewhere on the plane," the official told CNN's Barbara Starr.

[Iceheart]

With all due respect, I tend to disagree with my fellow armchair detective, if I may.

1) Plane was in relatively good condition and maintained adequately at least.

I'd rather state it as "aircraft-related paperwork was in good condition and maintained adequately". For a company that already had a hull loss due to inadequate maintenance (RA-85588, fire started by a short circuit), I wouldn't discount the possibility of taking some fatal shortcuts in maintaining their aircraft, as it did happen before.

2) Crew is experienced and rested

Experienced - yes, rested - how would you know for sure? I tend to agree though that crew action or inaction was, most likely, irrelevant to this particular accident.

3) No suspicious passengers onboard, no major delay or any other inconvenience through ground ops reported
4) T/O without issues and begin climbing OK

That's what we've been told so far, correct.

5) When reached about intended FL but before leveling something very brief (fraction of seconds) and violent happened INSIDE, plane was broken in parts and falls down.

Fair enough, although I wouldn't be so certain about the event taking "fraction of a second". It could just as well take, say, five or ten seconds, and again, one cannot really discount the possibility of a slowly developing, undetected malfunction that finally manifested itself as an in-flight breakup. (For once, imagine cargo hold smoke detectors inoperative.. not exactly an impossible scenario)

5.1) This event was so short that crew have no time to complete any action, so it's not stall or similar.

Or, alternatively, any actions of the crew were not enough to prevent the tragic outcome. Or, again, the crew could be unaware of a developing problem until it became too late. In any case, I agree that it's reasonable to discount the crew action as a direct cause of this event.

5.2) This even was followed (and possible is cause) of tail section detachment

Tail sections don't usually get detached by themselves, so this can't be attributed as a direct cause. An airplane that may, all of a sudden, shed its tail section by itself, is not exactly airworthy.

With all due respect, and no unconstructive criticism intended.

[CONSO]

1) at normal level cruise- HS may have a slight leading edge elevation to provide tail lift- leverage to keep nose down. But during climb, leading edge of HS may be slightly lower than trailing edge to keep nose up.

2) At the time of leveling off, elevator trim changes from a few degrees nose up to nose down for level flight

3) At that time- something breaks, allowing HS to flip leading edge UP. Being uncontrolled, leading edge approaches vertical, putting tremendous loads on tal section aft of RPB, and virtually tearing off both HS fairly cleanly external to tail cone area.

IMO clues to the above are

1) both HS missing
2) said motion would put a major tensile load ( HS section just before separation ) on top half of fuselage and at the production join circumferential ahead of RPB and aft passenger exit door.

3) lower part would crumple in compression and eventually ( in a few seconds or less be torn off.

4) Plane absent HS makes rapid climb- and possible roll due to both HS not failing exactly as same time- thus damaging aft VS ( rudder )

At that point- the high g loads etc take over and tear off parts of fuselage, etc. - the rest is history

Summary- IMHO some sort of jackscrew, pin, clevis , or control failure of parts which normally keep the HS from flopping around was the instigator

One clue might be the condition of the RPB other than impact damage. IN my scenario, it is not a player. The tail cone would not rip off the bulhead simply because aft is not pressurised and skin stresses via rivets and bolts on the rim are much lower.

Comments ??:uhoh:

[RTM Boy]

Reuters is saying that Egyptian sources close to the investigation believe there was an on-board explosion, although the cause is not confirmed.

Cause of Russian aeroplane crash looking more like explosion - source | Reuters (http://uk.reuters.com/article/2015/11/04/uk-egypt-crash-islamicstate-idUKKCN0ST1P720151104)

[Prada]

This is left side engine. you are watching at inner side of the pylon.

http://i.dailymail.co.uk/i/pix/2015/11/03/15/2E0F5DD600000578-3301094-The_investigators_have_identified_12_separate_debris_fields_ prov-a-27_1446563401024.jpg

Video for comparision: Chances are that you are watching at the actual engine.
https://youtu.be/JmZ_Qc_J9bk?t=7s

Picture from video:
http://www.keri.ee/crash/left_engine.png

[Kulverstukas]

Conso
3) At that time- something breaks, allowing HS to flip leading edge UP. Being uncontrolled, leading edge approaches vertical,

Again, I'm not familiar with construction but isn't here any natural limiters which prevent HS to travel more than allowed angle? As ex-engineer I will not allow any design without them.

Iceheart

1) Agreed about condition, still I'm sure this is not "живопырка airline" and not even close to condition of ill-fate RA-42434 so even if there was some issues I think we will newer found something major as for example total loss of thread on HS jack

5) I assume that preliminary CVR reading was done, that (looking at their photos) there was no technical loss of data and that real outcome from them was zero, no information of event which mean that CVR was lost before or in time of disaster and in sequence this mean that tail separation was inside of max couple seconds of event.

[ExpatChris]

Hi All

Forgive me I am but an interested SLF

Can somebody pls tell me why the UK and others have suspended flights, downed plane was not from UK and attack not in UK

Could they have received a threat ???

Help I am confused

Chris

[peekay4]

Loss of confidence in the Sharm el-Sheikh airport security procedures, and Egyptian security capabilities in general.

[RTM Boy]

A bomb on one plane at SSH could be on any plane - could have been a random act (ie to whichever plane the bomber could get access to) - we don't know - so anyone a possible target for all sorts of reasons

[Tarq57]

Hi All

Forgive me I am but an interested SLF

Can somebody pls tell me why the UK and others have suspended flights, downed plane was not from UK and attack not in UK

Could they have received a threat ???

Help I am confused

Chris
The news report I read this morning alluded to the possibility that airport security (vetting of bags, cargo etc) could not be guaranteed to be up to scratch.
The accident "fits'' with an onboard explosion, so until more is known this is a precautionary measure.
Makes sense to me.

[ExpatChris]

So a case of prevention better than cure then, thanks for info makes sense

Just being ultra cautious, author on Sky News states that IS could have infiltrated the ground crew

[Mauersegler]

So a possible Scenario remains: Something caused a rapid and massive excursion of the THS/Elevator. This causes the HS to fail. Aircraft starts to bunt over putting enormous load on the VS and rear fuselage, causing the fueslage directly aft of the CWB to collapse.

I think the same. Remarkable is the apparent symmetry of the damage overall. For me that speaks against a bomb, how probably would it be, that a bomb was placed in the center? (well, if somebody put it in the jackscrew or something like that, ok, but not if placed in baggage, loo, etc.).
I also think that the damage to the HS and VS could not happen once the tail was detached.

[StuntPilot]

CONSO:

That is also what I think. The decoloration in the HS torsion box and the fluid leaking outside point to an issue in this area. Also, the Metro Jet docs show that last year (in march) a C check was performed, not a D check.

[Toffee boy]

Engine failure followed by this kind of massive airframe failure would surely not occur in such a short timeframe that nothing is recorded on the FDRs? Engines are not bombs, they start to malfunction and then they disintegrate. Data would be recorded, and the pilots would see instruments recording odd parameters.

The lack of recorded info on the FDRs (I think we can assume there's nothing to be heard/recorded as they would have released details by now) is very reminiscent of the Ukraine Malaysia airlines incident... Massive loss of all system integrity caused by an explosion.

so if there is no trace of conventional explosive materials, what can cause such a loss of all systems that record what's happening in such a violent and instant way?

[32bttln]

(CNN)[Breaking news alert, posted at 3:15 p.m. ET Wednesday]

The latest U.S. intelligence suggests that the crash of Metrojet Flight 9268 was most likely caused by a bomb on the plane planted by ISIS or an ISIS affiliate, according to a U.S. official familiar with the matter. The official stressed that there has not been a formal conclusion reached by the U.S. intelligence community. "There is a definite feeling it was an explosive device planted in luggage or somewhere on the plane," the official told CNN's Barbara Starr.

The assessment was reached, the official said, by looking back at intelligence reports that had been gathered before Saturday's plane crash and intelligence gathered since then. The United States did not have credible or verified intelligence of a specific threat prior to the crash, however, the official said, prior to the incident, "there had been additional activity in Sinai that had caught our attention."

[Pontius Navigator]

ExPatChris, it is a classic case of stable doors.

If there is one airport where you can be sure that security if top notch it will be SSH for at least the next week.

[clareprop]

If it was IS, they would be crowing all about how they had done it...and it would be in HD, not some blurry video.

[Kulverstukas]

PN, I doesn't tell that there wasn't hull loses at FL.

What I mean is
1) there is almost any part of plane immediately located
2) Bot CVR/FDR found in near perfect cond.
3) Plane was in inhabited area with constant control from ground
4) and it SUDDENLY fall apart without notice...

StuntPilot Also, the Metro Jet docs show that last year (in march) a C check was performed, not a D check.

I'm not pilot/tech but on what was said on Russian forum, there is no such thin on Airbus as C/D check and this list is shows works done which is analog to Boeing D-check.

[G-CPTN]

A bomb on one plane at SSH could be on any plane - could have been a random act (ie to whichever plane the bomber could get access to)The downed aircraft was at Sharm overnight - a lot easier to gain access than a typical short turnaround by a LoCo.

'Bombproof' security of pax luggage wouldn't prevent this.

Stable door, horse, bolted.

As has been said - the terrorists only have to get lucky once . . .

[flt001]

Fly in and out of CAI fairly regularly and worth noting the security there actually has two levels. You can't get through to the check in desks without first passing through an initial baggage x ray and body check. You also are not allowed to proceed without a valid boarding pass or booking checked against the manifest (fun for standby staff travel).

Security is then conducted at the entrance to the gate waiting room, this has always seemed as effective as other airports to me.

Obviously this is Cairo not Sharm but I've also flown domestic from Sharm and I wouldn't have called it a dangerous airport (taxi speeds aside).

However my other experience of living/being in Egypt a lot is money always talks...

[Kolossi]

The pictures of the tailcone show a long section of pipework known to be (from schematics and factory photos previously posted) the APU fuel supply pipe.

_If_ the cone detached either as the initiating event or as a result of VS/HS fail, would not the yanking out of this pipe cause a fuel leak capable of causing an explosion? The length of the pipe shown probably isn't sufficient to reach the centre tank, but by my non-expert reckoning it would be forward of the RPB.

I'd have thought if the APU isn't running their would be an isolator on the fuel line hopefully at the tank, but what if that failed or was left open (yes I know, Mr Occam is getting less happy as I go on, but still...).

Lastly, is it at all possible that the APU was actually running during the flight? I imagine there would be plenty of cockpit indication of that but it would enable the fuel leak - or possibly even APU malfunction of some kind. From photos I'm not suggesting destructive failure of APU, but possibly vibration, along with corroded cone attachment due to skydrol leak assisting cone departure or somesuch ...

Happy for all above to be discounted, but for some reason that long intact pipe section in the APU cone photos intrigues me.

[oldoberon]

used these images as they are clickable to enlarge


(Clickable)
http://i.imgur.com/BsX3Y6Bl.jpg (http://i.imgur.com/BsX3Y6B.jpg)
http://i.imgur.com/6See3Zdl.jpg (http://i.imgur.com/6See3Zd.jpg)

look at right hand side image above, then look at image below

http://i65.tinypic.com/dmtx8k.jpg

what is that big grey chunk in the doorway, haven't seen it pn any images on prune.

[Chronus]

Hi All

Forgive me I am but an interested SLF

Can somebody pls tell me why the UK and others have suspended flights, downed plane was not from UK and attack not in UK

Could they have received a threat ???

Help I am confused

Chris

Answers:

Q1. In the interests of public safety. Given the possibility that it was an act of terrorism carried out with a motive to destabilise Egypt (and maybe even bring up on it the fate of the poor people of Syria) , through damage to its source of revenue from tourism, then a threat exists for all foreign tourists of any nationality.

Q2. Not known as none in the public domain at present time.

Here in the UK the press must be pacing outside Whitehall waiting for the press announcement after the PM`s Cobra meeting.

[Wycombe]

Fly in and out of CAI fairly regularly and worth noting the security there actually has two levels. You can't get through to the check in desks without first passing through an initial baggage x ray and body check. You also are not allowed to proceed without a valid boarding pass or booking checked against the manifest (fun for standby staff travel).

Security is then conducted at the entrance to the gate waiting room, this has always seemed as effective as other airports to me.


All of the above is irrelevant if the security threat is a person/persons with an airside pass and access to the a/c movement/parking/maintenance areas.

I suspect this is the focus of attention of the British "security experts" dispatched to SSH this evening.

[Kulverstukas]

Isn't it Engine #2 (starboard?)

http://s017.radikal.ru/i444/1511/3f/0d4c656ab173.jpg

[sardak]

conso,
ref 1) both HS missing
The left HS is shown in posts 730 and 762.

oldoberon, ref your interest in the aft frame at the HS,

Here is the frame during assembly. The large diameter tubes go to the pivot points of the HS center box, which are located on two fittings that span the gap between the upper and lower frames.
http://i.imgur.com/QdE4ydW.png

Those fittings and tubes are removed during the HS installation, shown in this screenshot at 5:30 in this video https://www.youtube.com/watch?v=03Zgs8WCArw This video also shows installation of the aft cone at 5:49, the VS at 6:15, the APU at 7:09 and one of the flight recorders at 7:32
http://i.imgur.com/YNJihUp.png

In the video you posted, https://www.youtube.com/watch?v=6OQigxFYIUg, the fittings and pivot point, but not the tubes, are shown installed at 2:05.
http://i.imgur.com/zPeddTF.png

And from the photo of the wreckage, two-thirds of that frame, other structure and the HS are gone.
http://i.imgur.com/il4E1GQ.jpg

[TURIN]

what is that big grey chunk in the doorway, haven't seen it pn any images on prune.

Toilet door? With cubicle assembly partly attached?

[DozyWannabe]

If I remember what I've seen and read regarding airliners brought down by bombs, the key technical difference when that happens has to do with metallurgy - IIRC a specific kind of "pitting" in the metal combined with the pressure vessel failing from the inside out. They've had people on the ground for long enough now that evidence of that nature is likely to have been found - enough to cause suspicion, if not certainty.

As far as the recorders go, I'm pretty sure that as long as the recording medium (the little grey cylinder bolted securely to the recorders) appears to be intact, there shouldn't be any issue with reading them...

[BARKINGMAD]

Engine associated "flash & thermal event"?

Airtours 732 at Manchester and 777 at LAX?

On ground, no airflow and no significant dynamic loading.

Luckily (for some) rapidly attended to by Fire/Rescue services.

Now try the same at 30,000ft, with the N1s and N2s at maximum, sometimes over 100% in the case of the N1s and a healthy draught to propagate the inferno and see what happens?

Just a thought from an old geezer who's read too many accident reports, in 40+ years associated with the profession with some memory chips still readable...........................:sad:

[Vector12]

The UK authorities suspect a breach of security at Shram El Sheik has allowed a bomb to be smuggled on to a plane. Due to their involvement in the Iraq bombing campaign against IS they feel more vulnerable than most countries.

[dsc810]

@dozywannabe

The little grey cylinder you mention bolted on the CVR and FDR is actually the underwater locator pinger.......

[AirculePoirot]

While no stone is being left unturned, here's another one:

Assuming that the cabin crew started heating food as soon as possible after takeoff, 25 minutes into the flight could conceivably be the time it takes for the food heaters to reach high temperature. One (or more) of those food packages could have been a bomb - disguised as a meal (breakfast?) – detonated by being heated to a moderately high temperature.

So obviously it would have happened in the rear galley, and powerful enough to knock out the rear section.

[anartificialhorizon]

I think we would have seen at least a Mayday call or a drift down, even with a catastrophic engine failure. At 30000ft, would a fire be difficult to start from something like a punctured fuel tank?

I cannot recall many high level airframe fires, explosions at (near) cruise altitude because of the environment up there.....

[DozyWannabe]

@dozywannabe

The little grey cylinder you mention bolted on the CVR and FDR is actually the underwater locator pinger.......
If that's so then I was misinformed - fair doos... I do remember that the medium was missing from one of the recorders they brought up from AF447, and that "pinger" part was also missing in the photos. I'm a wee bit confused now...

[EDIT : GIMF - It's the big red cylinder holding the media, the little grey one is the pinger, as you say. :) ]

[Kulverstukas]

Assuming that the cabin crew started heating food as soon as possible after takeoff, 25 minutes into the flight could conceivably be the time it takes for the food heaters to reach high temperature. One (or more) of those food packages could have been a bomb - disguised as a meal (breakfast?) – detonated by being heated to a moderately high temperature.

Not bad. :ok:

But still I have no clear signal that bomb IS located. All investigation and security activity we are aware of just shows us that any other version was weighted and found less possible... :ugh:

[BARKINGMAD]

"I cannot recall many high level airframe fires, explosions at (near) cruise altitude because of the environment up there....."

DC10 which ended up at Sioux City to name only one............?

No airborne fire, but the engine disc which exploded didn't have wing tanks to puncture.

[mm43]

@DozyWannabe,

The ULB Pinger(s) were never located, nor were heard during the AF447 search. That is, both the DFDR & CVR were found minus their pinger.

[StuntPilot]

What would happen with an A321 upon a jackscrew failure? Will the HS make a very large rotation or will it be stopped at a limiting angle before forces can get to the point of HS dislocation (hinge failure) or destruction? https://www.youtube.com/watch?feature=player_detailpage&v=JD7FmX0hr6c#t=1850 (https://www.youtube.com/watch?feature=player_detailpage&v=JD7FmX0hr6c#t=1850)

[AirculePoirot]

Its placement would have to be quite close to the tail, based on the scarcity of additional debris found near the tailplane wreckage, and a pretty powerful one at that, given that the tail is generally considered as the most structurally robust part of the aircraft, n'est-ce pas?

[DozyWannabe]

The ULB Pinger(s) were never located, nor were heard during the AF447 search. That is, both the DFDR & CVR were found minus their pinger.
Right - One of the recorders was missing the big red cylinder (with the recording medium) IIRC, but it was found on a subsequent dive. Either way, as long as the medium container is more-or-less intact, reading it should not be an issue...

[thecretinhop]

long time lurker, keep up great work guys. as regard heating food, I am I wrong in thinking The caterers who bring food to truck was brought in for questioning?
Thought I read it somewhere. As many have said the mix of complex questions, lack of full data and geo politics make this very hard call. explosion does now look likely though Imo.

[foxmoth]

Can people please stop referring to this terrorist group by their chosen name and instead use DAISH/DAESH which gives them less legitimacy!:mad:

[oleostrut]

"
Its placement would have to be quite close to the tail, based on the scarcity of additional debris found near the tailplane wreckage, and a pretty powerful one at that, given that the tail is generally considered as the most structurally robust part of the aircraft, n'est-ce pas?"

It takes a surprisingly small amount of explosive to remove the tail from a pressurized airliner at altitude.
Less than the size of 2 cigarette packs.

Placement isn't all that critical, either.


Tests were done after Lockerbie, you can see the results on Youtube

[Biggles1957]

BBC News update

Sinai plane crash: Bomb fears prompt Sharm flights suspension - BBC News (http://www.bbc.co.uk/news/uk-34724604)

A senior UK government source [un-named] told the BBC that fresh intelligence to emerge during the last 24 hours pointed towards a bomb causing the crash.
Egypt's foreign minister, Sameh Shoukry, said he was very disappointed by the decision to suspend flights, accusing the UK government of making "a premature and unwarranted statement" on the crash.

[thecretinhop]

Russian plane tragedy: Investigators probe caterers amid evidence of 'inside explosion' | World | News | Daily Express (http://www.express.co.uk/news/world/616962/Russian-crashed-plane-Egypt-investigators-question-caterers)

[DozyWannabe]

Can people please stop referring to this terrorist group by their chosen name and instead use DAISH/DAESH which gives them less legitimacy!:mad:
In real terms, whatever they are called has no effect whatsoever on their legitimacy - the whole "DAESH" thing started because it happens to sound similar to a derogatory term. Strictly speaking all it'll do is antagonise them (not a good idea IMO), and frankly it's a bit puerile.

Far more important, it has yet to be confirmed that the aircraft was bombed, let alone which individuals or group were responsible; so bringing that particular group up now - whatever one chooses to call them - is just giving them publicity they don't need.

If this crash *was* the result of a criminal act, the "how" and "why" is currently a lot more pertinent than the "who".

[RexBanner]

I know that the Russians have recently started bombing in Syria but, given the UK is probably up there with the USA in terms of a target, why Metrojet rather than easyJet or BA for example? (Both of which fly into SSH). They've had the means and opportunity for months now if the theories on here are correct. That's why I'm still erring on the side of structural/technical as it stands.

[Kulverstukas]

I just leave it here - HS part of tailcone from inside:

HS servo
https://img-fotki.yandex.ru/get/46165/61625582.78/0_1c3d24_22aad2e0_XXL.jpg

CVR/FDR left, HS screw and HS center
https://img-fotki.yandex.ru/get/15575/61625582.6a/0_147002_d8f86ef_XXL.jpg

[Kulverstukas]

RexBanner, as was already mentioned here, possible that they just used first opportunity which they can grab. And at the charter plane which sits here overnight it was much more simple than at half an hour turnout lowcoster.

[AlphaZuluRomeo]

[...]AF447 [...]That is, both the DFDR & CVR were found minus their pinger.
Nope. CVR retained its pinger.
http://www.bea.aero/fr/enquetes/vol.af.447/images/cvr1.jpg

[Kulverstukas]

Fresh video from search operation

Video (http://www.vesti.ru/doc.html?id=2683154&tid=108965#/video/https%3A%2F%2Fplayer.vgtrk.com%2Fiframe%2Fvideo%2Fid%2F14400 82%2Fstart_zoom%2Ftrue%2FshowZoomBtn%2Ffalse%2Fsid%2Fvesti%2 FisPlay%2Ftrue%2F%3Facc_video_id%3D661534)

Seems all a/c parts already collected and EMERCOM team is after all small debris.

[750XL]

Does anyone know whether Metrojet are even catered in SSH? In line with other charter airlines, I wouldn't be surprised if they return catered from Russia?

[smurphy]

Latest update: Summary - FCO advises against all but essential travel by air to or from Sharm el Sheikh airport

https://www.gov.uk/foreign-travel-advice/egypt

[Kulverstukas]

750XL, good point!

[Kulverstukas]

21:00 (04.11.2015)*|* (http://tv-news-online.com/programma-vremya-v-21-00-04-11-2015/)

From 17:00

Look at row of seats at 17:50