BREAKING NEWS: airliner missing within Egyptian FIR [Archive] - Page 7

CONSO

6th Nov 2015, 22:21

You raise the same issue- reasons I stated in my post
#1306 (http://www.pprune.org/9171252-post1306.html) (permalink (http://www.pprune.org/rumours-news/569907-breaking-news-airliner-missing-within-egyptian-fir-post9171252.html))

but more terse and simple.

IF aft section torn off by explosion and pressure issues ahead of PB, then HS and VS would be a relatively complete unit and as it fell would generally align itself to minimum drag or if not would not develop enough " leverage" ( opposite force ) to rip off HS external to tail section- thus landing almost intact but for impact damage. But photos to date do not support this analysis.

I note that CVR and FDR were ' recovered ' and probably were part of tail cone aft of PB since that was the location- but NO- repeat NO photos of nearby jackcrew and internal HS ' wing" Box which is more massive than the nearby skin/stringer attachments/shelves holding the CVR-FDR.

Something is still missing from released info :ooh:

ROKNA

6th Nov 2015, 22:21

Was a QAR fitted? Doesn't look like it would have survived regardless

dechelski

6th Nov 2015, 22:25

I have a feeling that the truth will be out tomorrow, after the Egyptian's press conference. I think they are feeling stuck between a rock and a hard place. Come out with what they know to be true so far, or continue to have a rapid demise/disrupt in their tourist industry / country.

I still don't feel that a bomb is responsible. An explosive decompression would sound the same as an explosion caused by a bomb no doubt?

Secondly, a bomb that would clearly have to be located in the rear of the aircraft - either on the passenger section, or below in cargo. I find it impossible to believe that a bomb could be placed in the cargo hold and not damage any luggage / suitcases etc. The pictures we have seen so far, they have looked in pretty good condition despite what's happened.

A bomb on the upper deck would surely demonstrate more shrapnel damage and/or leave behind a trace that any fully trained investigator would be able to spot?

My money is still on the tail strike incident. I imagine a charter plane would be treated in a similar manner as a courtesy car would be. Maintained to the bare minimum/legal requirement and slightly lax care/consideration for it.

Bertie Bonkers

6th Nov 2015, 22:29

If the tailplane came loose from the jackscrew, there would be a very short interval before breakup where various flight parameters would depart from norm.

True. But looking back at Kulverstuka's photo of the internal HS assembly & seeing how close the front edge sits to the back of the recorders where the connections go in, if that front edge took out those connections it would be a #very# short interval. There might be a brief period of continued recording life while any capacitors in discharged, but then factor in buffering...

hamster3null

6th Nov 2015, 22:29

So, discounting a SAM, as I think is consensus anyway, the other option is a bomb. Seems to me there are three ways to detonate it:
a. pressure/altitude
b. timer
c. remote from the ground.

Now, in order to film this event the camera would have to be extremely close to the flight path.

For a. they'd have had to be directly under the aircraft just as the nominated altitude was reached, possibly needing to know QNH at that point? Implausible.
For b. they'd have had to be directly under the aircraft just as the timer reached its appointed moment. Implausible, given the unpredictability of actual departure time, weather and winds, routing, etc.
For c. they'd have had to be directly under the flight path (how hard is this to predict within a margin of 2-3 miles? I don't know but I'd imagine quite tricky) and known which flight was overhead and had the technology to detonate the bomb remotely from about 6 or 7 miles, which, again, I've read elsewhere is not necessarily easy. For mine, also implausible.

If they can film the explosion at all (which most certainly can't be done with a cell phone and requires either a serious video camera with a 300 mm + telephoto lens, or a telescope), they can handle being up to 10 miles away from the epicenter without significant loss of visual quality.

Getting within 10 miles of the flight path is not a big deal, since it follows predetermined flight points. Timing the explosion is the real challenge, if it's on a timer rather than remotely detonated: their margin of error is +/-2 minutes, tops (if the departure is delayed even for 5 min, the explosion will be too far to film.)

NSEU

6th Nov 2015, 22:30

Why are there not two sets of CVR and FDR, one at each end of the aeroplane ? There are backups for lots of other systems.

The recording system on a typical aircraft consists of 1001 sensors all over the aircraft, a box for collating the data (typically just aft of the cockpit where most of the airplane computers and sensor analysers are*), the recorders in the tail, and a number of power supplies to drive these devices. A system is really only as strong as it's weakest link. Such a catastropic event where the aircraft is breaking up in flight will (IMHO) not give much additional data. Whilst the data module of recorders are able to survive fire and 3400g crashes, obviously the other components of the system are not designed to survive a fraction of this.

The recorders are usually powered by normal aircraft power (not batteries). Even if you made the CVR/FDR battery powered, you still need power to the other 1001 components to get all data.

*Probably to minimise length of databus wiring.

Lancair70

6th Nov 2015, 22:33

Cubemaster, I understand that but these CVR and FDR seem to go missing or be damaged to be unreadable or inop while a/c continues on before eventual end. A 2nd set in this case would potentially have more data.

aterpster

6th Nov 2015, 22:33

If this crash was the result of a bomb (as the French media asserts), it is absurd for the authorities to claim the investigation "has to run its course." If they have sufficient evidence that it was a bomb, then it becomes primarily a criminal investigation, in which case the information should be released by law enforcement without the full press of an accident investigation.

The accident investigation should continue, of course. But, in parallel with the criminal investigation.

At least that is the way it would work in many countries, including the U.S.

MrSnuggles

6th Nov 2015, 22:37

More about the black boxes.

And PLEASE note the wording in the original text, my translation is only a translation.

Crash dans le Sinaï : l'attentat confirmé par les boîtes noires - Le Point (http://www.lepoint.fr/monde/sinai-l-attentat-confirme-par-les-boites-noires-06-11-2015-1979795_24.php)

Selon la source citée par l'Agence France-Presse, les photos des débris montrent que certains sont criblés d'impacts allant de l'intérieur vers l'extérieur de l'appareil, « ce qui accrédite plutôt la thèse d'un engin pyrotechnique ». My translation:
The source* cited by AFP expressed that the photos of debris had certain impact damages on the interior versus the exterior of the airframe << that very well could credit the hypothesis of a pyrotechnic event** >>.

*in context, this source seems to be the same source cited earlier, I made a translation of that a few pages ago.

**engin can mean both "engine" and "method by which something is driven/propulsed in the wanted direction"

mickjoebill

6th Nov 2015, 22:46

My professional view of the video is that it is a fake.

1/ the black smoke trail and the aircraft werenot shot at the same time and so have been composited.
The composite is then played on a TV and recorded on a cellphone with some eggagerated wobble.
The frequency of the wobble is not characteristic of footage taken with a long lens of a subject at least 7 miles away.

2/ The deep smoke should exhibit the same tones as the underside of the fusalege, but it does not, it is far cleaner and a deep black without any atmospheric haze or lens distortion. Refer to the black on-screen logo top right as a reference, the black smoke is the same clean and deep black as the logo.

3/ Perspective of the smoke trail is also wrong.
It appears to be taken from a following aircraft and could be a doctored shot of a white contrail or even footage from a gun camera of an unrelated explosive event.

4/ Given the time of day (full sun) and subject to camera distance the initial flash is unlikely to be registered by the camera as a clean, well defined, pure white.

5/ where is the shot of the aircraft falling to earth?

Mickjoebill

HarryMann

6th Nov 2015, 23:11

Of relevance to Sharm safety...

Daily Mail (front page) tomorrow reporting that the cockpit crew of a Thompson flight on August 23rdsaw a missile pass within 1000 ft of their aircraft whilst near SES.
No altitude given..
Suggests Egyptian military admitted a test firing... which UK Govt. accepted
Cockpit crew kept quiet until now...

oldoberon

6th Nov 2015, 23:16

Are there any skydivers on this forum?

Looking at the girl's picture at LED airport, I'd guess she weighed about 15 pounds (7 kg). As such she'd probably be ranked as a "slow" faller in skydiving parlance.

Can someone with the right knowledge, and a winds aloft report, compute how far she might have drifted in a 31,000 foot fall?

mach411 post 1360_

With respect to the position the toddler was found, I think RYFQB solved the mystery in post #1359. When the body was found, it appears that according to TASS the most recent search area completed was 33 square kilometres. 33 kilometres is 20.51 miles, so the most likely explanation is the information was misreported as direct distance of 20 miles from the main crash site.

Given the 33 km^2 area, if we assume a circle, the body was actually found no more than 3.24 km away from the main crash site.

pls note #1359 is not by RYFQB, so ether number is wrong ot post1359 deleted

OTOH

Oleostrut says

"Given the 33 km^2 area, if we assume a circle, the body was actually found no more than 3.24 km away from the main crash site."

Reports on finding the toddler were very clear she was found a great distance from the crash site. Greater than 21 miles was what was reported, and investigators needed to greatly expand their search area, especially along the earlier flightpath.

Nowhere in any of the reports was there any ambiguity as to the child being found distant from the crash site.

Right Way Up

6th Nov 2015, 23:19

Harrymann....

I heard a rumour on our company website that this also happened to Thomsonfly at DLM but there was no further mention until I saw the media article today. I think there are some very serious questions to be asked of the authorities.

HarryMann

6th Nov 2015, 23:22

Pilotsresearch.......

I have an image of a geeky teenager with no social skills......REALLY?

Harrymann....

I heard a rumour on our company website that this also happened to Thomsonfly at DLM but there was no further mention until I saw the media article today. I think there are some very serious questions to be asked of the authorities.

Yes indeed... dangerous military exercise or cover up you mean ?

Alain67

6th Nov 2015, 23:26

An explosive decompression would sound the same as an explosion caused by a bomb no doubt?
IMO a spectral analysis would look different.

Alain67

6th Nov 2015, 23:30

In this context, French "engin pyrotechnique" means pyrotechnical device.
(English engine is "moteur" in French)

Etud_lAvia

6th Nov 2015, 23:57

Some recent posts have expressed skepticism about the interpretation of the final "noise" recorded by the CVR.

As an avid student of accident investigation, I have seen some instances over the years (no citations at the moment, I don't recall the specific accidents) in which fairly detailed inferences were made from CVR data.

Most obviously, the pressure level of a noise or shock can be estimated from the CVR recording. This in itself may be very useful in distinguishing a chemical explosion from an impact, metal fracture, or explosive decompression. Given the circumstances of the doomed flight, it's possible that the CVR recording captured several of these in NEAR synchrony -- tiny differences in timing will themselves serve as forensic clues.

Further, modern airliners are fitted with multiple Cockpit Area Microphones (CAMs). Comparing recordings from the various microphones can help to localize the direction from which the sound came, and to distinguish a loud sound from a shock wave*.

Conclusion: the investigators may have learned much more from the CVR, than the presence of a Loud Bang.
______________________________

* I've no idea how far the shock wave from a reasonable-size IED can travel in an A321 fuselage, so I can't say whether it's possible that an explosion far aft would produce a shock wave at the cockpit.

Old Boeing Driver

7th Nov 2015, 00:43

What I meant was that for a small price, extra, unattended, heavy, or extra luggage can be loaded in the hold by the handlers. it is probably done everyday.

As you can see from another poster in France, the rule doesn't even exist there.

The flight crew would have have zero knowledge of any extra or unattended bags.

Having spent a lot of time in that part of the world flying commercially, unfortunately, I have seen things like this occur.

CONSO

7th Nov 2015, 00:49

Alain67 (http://www.pprune.org/members/444706-alain67) 1527 post said IMO a spectral analyis would show the difference.

Right on- consider a major difference

An explosion makes as major increase in a positive pressure ( simplified as blowing into a ballon to inflate it )- and then followed by a decrease in pressure. As pressure decreases, sound intensity decreases- probably with little echo- Sound **speed** is a function of temperature not pressure. rapid decompression lowers temperature.

A decompression makes a major decrease in pressure.

Now both can sound the same to the ear- but any spectral analysis from several mikes should be able to immediately determine which happens first

j71

7th Nov 2015, 01:13

@hamster3null: timing the explosion may not be that hard.

A mobile phone, or some other computing device with wireless communication, could easily talk to another device on the ground and update/modify an agreed upon deadline until contact is lost between the device on the ground and the on-board device. The last agreed upon time would be available to the second for whoever planted the device and their friends.

Letting the devices update the deadline automatically has the advantage of not involving the planter (no suspicious activity close to the plane) and you can do it frequently right up to the point of losing connection.

As for losing connection, this would depend on whether you use cellphone connections or wireless. Wireless might be cut when the doors are closed or, for instance, a catering truck with the ground device leaves the plane. Whether this is good enough depends on how smooth things normally go at the airport (never been there, so I wouldn't know).

I guess cellphone coverage for a planted device might last until you get up to a certain altitude at least? That would let the perps update the deadline based on exact takeoff time. SMS messages would give you plenty of bandwidth for final agreements (deadline update + ack), so you don't really need wireless.

If you assume that the mobile phone can connect to on-board wifi or cellphone networks, you will have more options for factors that can update the deadline (and still keep "ground" updated):

a) pressure as measured by the phone (my old Samsung phone does this, for instance)
b) location available through on-board wifi webpages (for instance). You probably don't need working GPS as the plane might give it to you freely
c) "ground crew" can update the deadline

Programming the devices isn't that hard. You don't have be a very advanced programmer to combine multiple techniques to get whatever works best that day.

1) If you only need it to go off some time after reaching a given altitude/pressure, it's almost trivial (depending on how safe you want to be that it doesn't go off early, but you might add other safeguards than programming).

2) If you need it to go off at a known point in time that's updated to the point of losing connection, it's really not that much harder and you can just set the deadline to a point where you're fairly certain it's well up in the air.

3) If you want to let it go off when passing a certain point (to some degree of accuracy), it's not really that much harder than (2). It's just down to how accurate you need to be, assumptions on flight paths and how long you can keep updating the timer. On-board communication at altitude can add accuracy, but would be more vulnerable and might be slightly more complicated to get working reliably.

Not that I want to argue that the video is real. I just don't think timing is an argument for debunking it.

papershuffler

7th Nov 2015, 01:15

Crash dans le Sinaï : l'attentat confirmé par les boîtes noires - Le Point
Crash dans le Sinaï : l'attentat confirmé par les boîtes noires - Le Point (http://www.lepoint.fr/monde/sinai-l-attentat-confirme-par-les-boites-noires-06-11-2015-1979795_24.php)

Quote:
Selon la source citée par l'Agence France-Presse, les photos des débris montrent que certains sont criblés d'impacts allant de l'intérieur vers l'extérieur de l'appareil, « ce qui accrédite plutôt la thèse d'un engin pyrotechnique ».

According to the source quoted by Agence France-Presse, the debris photos show that some are riddled with [impacts - shrapnel?] [going] from the inside [towards] the outside of the [aircraft] - which supports the theory of a pyrotechnical device.

criblés - 'riddled' - not evidenced in the photos here thus far, but genuinely crucial pieces may have already been removed, or not for public consumption.
Also, some debris 'may' be riddled on the inside, but have landed with the exterior up, so the damage isn't immediately visible without turning over.

I find the use of 'l'intérieur' interesting - when I first read that, I assumed it was meant to be passenger cabin, rather than somewhere like the the baggage hold. 'Inside' is a lot more vague.

From earlier in the article:

Le Cockpit Voice Recorder (CVR), l'une des boîtes noires, ne demande pas d'interprétation compliquée lors de la lecture, si ce n'est la traduction de propos en langue étrangère. Ce n'est qu'un magnétophone qui enregistre les conversations et les bruits du cockpit. Il révèle qu'une explosion est survenue. Ses effets dévastateurs ont coupé l'alimentation électrique de l'avion permettant, entre autres, les enregistrements des données dans les boîtes noires.

The Cockpit Voice Recorder (CVR), one of the black boxes, requires no complex interpretation when reading, if this is about the translation of a foreign language. This is only a tape recorder that records conversations and sounds in the cockpit. It reveals that an explosion occurred. Its devastating effects cut the electrical power from the aircraft to, amongst other areas, the recording of data in the black boxes.

'no complex interpretation'??? - I think anyone with knowledge of previous incidents would beg to differ!

Caractère « brutal, soudain »

Le deuxième enregistreur, le Flight Data Recorder (FDR), capte des milliers de paramètres sur le vol concernant la vitesse, l'altitude, le régime des moteurs, le mode de pilotage, la position des gouvernes, etc. Pour cela, l'avion est truffé de capteurs. Une analyse fine au 1/100e de seconde des arrêts de ces capteurs permettrait de préciser la position dans l'avion de l'engin explosif. Selon une source proche du dossier citée par l'Agence France-Presse, le FDR confirme le caractère « brutal, soudain » de l'événement qui a précipité la chute de l'appareil. « Tout est normal, absolument normal pendant le vol, et brutalement plus rien. Cela va dans le sens de la soudaineté, du caractère immédiat de l'événement. »

A "brutal, sudden" nature

The second recorder, the Flight Data Recorder (FDR), captures thousands of parameters on the flight regarding speed, altitude, engine speed, steering mode, the position of control surfaces, etc. For this, the aircraft is loaded with sensors. A detailed analysis of 1/100th of a second of the [last] of these [readings] would clarify the position on the plane of the explosive device. According to a source close to the case quoted by Agence France-Presse, the FDR confirms the "brutal, sudden" nature of the event that precipitated the fall of the [aircraft]. "Everything is normal, absolutely normal during the flight, and suddenly nothing. This [is] in line with the suddenness, the immediacy of the event."

Interesting that they think the sensors will reveal the device location. Would prefer to see the original AFP info - this article has certainly lent their own interpretation already to the few facts.

Brackets denote my interpretation of the original French.

(thanks to Mr Snuggles for the original link.)

G0ULI

7th Nov 2015, 01:17

CONSO

You are perfectly correct, so long as the CVR continues to record for a few seconds after the initial pressure wave from either an explosion or explosive decompression. If the explosion or decompression event severs the data lines to the CVR at the instant it happens, only an initial high spike will be recorded and the remainder of the data is lost. So the vital reverberation information that would distinguish between an explosion or explosive decompression is not available for analysis.

It may be possible to estimate the strength of the initial leading edge of the pressure wave from the rise time before the signal to the CVR was lost. Slight time delays between the different microphone pickups can be used to localise the source. The further away the noise originated, the less accurate this will be. So an event at the rear of the aircraft can be positively identified as originating from that area, but whether it was behind the wing, in a rear baggage hold, or in the tail section will be very difficult to establish with any degree of accuracy.

YetAnotherLurkingSLF

7th Nov 2015, 01:32

papershuffler has the gist of it

criblés d'impacts allant de l'intérieur vers l'extérieur de l'appareil

"riddled by impacts passing from the interior of the plane to the exterior"

Le Cockpit Voice Recorder (CVR), l'une des boîtes noires, ne demande pas d'interprétation compliquée lors de la lecture, si ce n'est la traduction de propos en langue étrangère.

"The CVR, one of the black boxes, does not call for any complex interpretation other than the translation of comments in foreign languages. It is just a tape recorder that records conversations and sounds in the cockpit. It reveals that an explosion occurred. Its devastating effects cut off the electrical power of the aircraft which allows, inter alia, the recording of data in the black boxes".

[I'm a translator with minimal relevant technical knowledge beyond what I pick up reading here, but even I can tell bad journalese when I see it]

NB that the French "brutal" is weaker than the English homonym - means little more than "abrupt" here

Une analyse fine au 1/100e de seconde des arrêts de ces capteurs permettrait de préciser la position dans l'avion de l'engin explosif.

"Analysis down to the nearest 1/100th of a second of the times these sensors failed would make it possible to identify the precise location of the explosive device in the aircraft."

[is that plausible? Presumably less likely if the event severed the connection to the FDR itself?]

oldoberon

7th Nov 2015, 01:40

Papershuffler

'no complex interpretation'??? - I think anyone with knowledge of previous incidents would beg to differ!

I think what he is saying is unlike the FDR which charts and figures, this is just sound so you can hear it, as oppose ti interpret what those sounds may mean/reveal.

Regarding FDR and sensors depending where the explosion was and whether it or the end result in the rear severed the cabling there maybe some useful sensor info if they are lucky.

Basically they need duplicate cvr/fdr in the front or go to what what being propose during MH17 and have continuous data streaming of both, to an independent storage source which over writes BOTH at the same frequency as FDR (to avoid losing what may be useful cvr on long flights)

CONSO

7th Nov 2015, 02:03

You are perfectly correct, so long as the CVR continues to record for a few seconds after the initial pressure wave from either an explosion or explosive decompression.

Keep in mind- some still believe the CVR is a tape recorder- the unit specifically shown as recovered - and in apparently good condition is a solid state device as described on the label.

As to the initial pressure wave- positive or negative- unless the explosion happened to immediately sever both power and multiple mike data lines at the same time, some trace should be available.

Ditto for a structural failure unzipping of aft section- which **might** give a few milliseconds more of data before both data and power lines are pulled apart.

yet the press and supposedly officials are saying definitely an explosive device ???

So why are there NO pics of jackscrew and horiz stab ' wingbox ' ??:ugh:

lomapaseo

7th Nov 2015, 02:13

For interest

There are pressure waves and structural borne waves, both longitudnal and lateral along the planes axis. The structure borne waves arrive the quickest and the decoding of these relative to any pressure waves is key to the location of the hammer blow etc.

Unfortunately or fortunately there is a data bank of previous CVRs to compare against, both for bombs and structural only failures.

I'm in the wait and see mode for what cards will be released in the news on this.

Etud_lAvia

7th Nov 2015, 02:38

@Sultan,

I respectfully suggest that the account you offered of flight recorder performance in the helicopter accident reflects an imperfect recollection or interpretation of the events. I have two reasons for this:

1) Usually when buying a car, we don't ask, "does it have a motor, or is at least designed to be fitted with one?" ... because everyone understands that cars need motors! When specifying or designing a flight recorder, it ain't necessary to spell out "this thing should record data right up to final impact," because everyone knows that's the FUNDAMENTAL PURPOSE of a flight recorder. N'est ce pas?

2) I have reviewed Aviation Investigation Report A09A0016 (http://www.tsb.gc.ca/eng/rapports-reports/aviation/2009/a09a0016/a09a0016.asp) issued by Canada's Transportation Safety Board, concerning the fatal ditching on 12 March 2009 of a Cougar Helicopters' Sikorsky S-92A.

This report says, "The MPFR* stopped recording about 44 seconds before impact and then began recording again about 1.7 seconds before the impact." The report attributes the data loss to an interruption of power to the recorder. Further, it finds that the likely cause of power interruption was activation of a g-switch intended to stop flight recorders when a crash occurs (?!?!).

If this is indeed the accident to which you refer, and the report is correct, then about 42 seconds of data were lost. Much more importantly, the quoted statement implies (strongly, to my mind) that the recorder captured and stored data up to the time of power interruption, and that recording promptly resumed when power was restored.

The report makes no reference to recorder buffering, latency or delay as a cause of the flight data loss. The report's sole finding with respect to the flight recorder, is that the use of g-switches to stop flight recorders is likely to result in data loss in future aviation incidents.
____________________________________________

If I've gotten any facts wrong, or misinterpreted anything, I welcome correction.

*Multi-Purpose Flight Recorder, a combination CVR/FDR

Machinbird

7th Nov 2015, 02:52

Wouldn't an high explosive event in the tail likely sever the electrical connections to the CVR before the sound could travel through the air to the microphones in the cockpit?

The speed of sound in Aluminum is about 15 times faster than the speed of sound in air. An explosive event would be rich in high frequency components and would travel through the structure and in effect, shake the structure holding the microphones and generate a signal in that manner. There would be a number of potential methods of analyzing the signals from the various cockpit microphones to confirm an explosive event.

If the event acoustic signal in the cockpit is an air carried signal, then the likelihood of a structural failure cause for the sound would be very high.

thcrozier

7th Nov 2015, 03:04

It would travel through whatever medium at only a fraction of the speed of light, and then get back to the recorders in the tail at a theoretical limit of light speed. In actuality the return trip would be much slower. Summing up the two, the cables could have been severed before the round trip was over.

But, as has already been mentioned here, the actual severing of the cables may have sent a final signal to the recorders.

tdracer

7th Nov 2015, 03:41

I've been intentionally staying out of this one, but something to consider:

I have little knowledge of the A320 series (given I work for brand B), but it is normal to provide significant separation between wire bundles to minimize the risk of a single failure taking out multiple systems. So it is reasonable to assume the wire routing to the CVR and DFDR were separated by several feet.
Pure speculation here, but it's quite possible that (assuming a bomb blast), the initial blast severed the wiring to the DFDR - hence no useable data. But some of the wiring to the CVR survived the initial blast. The bomb blast compromised the the fuselage and small debris exited the airframe (such as the unfortunate infant) while the pilots attempted to maintain control of a critically damaged aircraft while donning their oxygen masks (far too busy to contact ATC). Despite their best efforts, within a minute or so the aircraft completely broke up.
Again, purely speculation on my part, but it does fit the known data rather well.

VNee

7th Nov 2015, 04:10

Regarding the rumour of 2 minute buffering of DFDRs - something
got lost in translation here and cannot be true. Furthermore, the
following specifications are listed for FDRs in EUROCAE ED-112
document, entitled "Minimum performance specifications" (PDF p.167):

Altitude/Speed/Heading: 1 Hz
Acceleration: 8 or 4 Hz
Control surfaces: 16 Hz
Pitch: 4 Hz
Roll: 2 Hz
Yaw: can't find it!

A copy of the full document is located here:
http://tinyurl.com/pen8ol6

@Etud - speaking of translations, here's a quick one:
It's not "Ne c'est pas?" but "N'est ce pas?"

Now back to regular programming...

Etud_lAvia

7th Nov 2015, 04:15

thcrozier, you meant speed of sound, of course ;) Both denoted by c
______________________________________

So, how might the CVR record the sound of a tail explosion via microphones in the nose?

To begin, I suggest that the investigators will probably be able to distinguish a microphone signal from a signal resulting from mechanical disturbance of the recorder and its wiring. (In electronic engineering, the generic term for this second category of signal is "microphonics".) To begin, the microphones probably have a well-characterized response to sound impulses which is quite slow in electronic terms. A microphonic signal resulting from a violent impact is likely to have a much steeper rise time.

Ordinary sound would take about 0.1 seconds to travel the length of the A321 pressure vessel.

From a high explosive, the pressure front would travel some part of the distance as a shock wave (supersonically) ... potentially at more than 10 times the speed of sound. Depending on how far the shock wave can propagate, the travel time might be substantially reduced.

To the extent that sound is conducted through the structure of the fuselage, it could reach the cockpit in 0.01 seconds, or even less.

So, if the CVR can survive as long as a tenth of second, or even less than that, it could be able to capture the sound of an explosion taking place quite near to it.
______________________________________

How long, then, might the CVR survive?

A high explosive shock wave can travel so quickly (possibly 20 times the speed of sound), that for the purposes of this disaster it is reasonable to estimate the travel time (from the point of explosion to the solid objects between that point and the CVR) as zero.

But in the path between a galley-area explosion and the CVR, there are several layers of material, including the structure of the galley itself, linings, insulation, and the pressure bulkhead.

The shock wave can get around these objects to the extent that gas-leakage paths exist, or are opened by the shock wave itself. However, the wave reaching the CVR probably didn't stop its functioning. It is a very hardened unit, and the intensity of the pressure wave was necessarily dissipated to some degree by the time it reached the CVR.

Most likely, what stopped the CVR was direct mechanical impact by parts of the airplane on the CVR itself, or its cabling.

Considering one possible sequence:

the blast wave (by a perhaps circuitous path) reaches the pressure bulkhead
concurrently, overpressure both deforms & breaks the galley structure, and propels the pieces rearward like a piston
in response to overpressure, and perhaps also the impact of objects that have become projectiles, the bulkhead deforms, first elastically and then plastically
deformation of the pressure bulkhead exceeds its structural capacity, opening a rupture
from this point, continued failure of the bulkhead is progressive ... the blast overpressure may already be dissipating, but cabin pressure is exerting about half a ton per square foot on the now compromised bulkhead
static pressure and the dynamic forces from egress of cabin air peel open the initial crack(s)
bulkhead material, or other pieces from the aircraft that have become projectiles, strike the CVR and/or its wiring

Certainly, the actual sequence could have been a lot different from that. It would depend on which is the fastest route through the points of least resistance.

Although all these hypothetical events happen very fast, none of them are instantaneous. They all take time, and to some extent they are sequential (that is, one event does not begin until a preceding event has progressed to some extent).

I think it is plausible, and even probable, that whichever object hammered the CVR or its cabling could have taken a tenth of second to get there.

The blast wave can travel 20000 feet per second, but the solid object that killed the CVR may have been travelling more like 100 feet per second. Whatever speed it was going, it had to be accelerated to that velocity: it didn't reach it instantaneously.

Wannabe Flyer

7th Nov 2015, 04:27

slats11

7th Nov 2015, 04:33

I am beginning to think that some people know a lot more than we are being told now.

Almost certainly. We also saw that with MH370 and GermanWings.

tdracer

7th Nov 2015, 05:01

Quote:
I am beginning to think that some people know a lot more than we are being told now.
Almost certainly. We also saw that with MH370 and GermanWings.

Having been involved in a few accident investigations, that part is basically guaranteed. Once you're involved, you are basically under a gag order regarding the accident - unauthorized data release is career limiting (or even career ending). Data releases are to come via authorized channels. Further, even authorized data releases are strictly limited - unless - there may be an imminent air safety risk. Compromised security at a particular airport would qualify...

thcrozier

7th Nov 2015, 05:11

Etud, I was commenting on Machinbird's question, which I interpreted (and I welcome his correction) as:

"If an event produces sonic waves at the rear of an airplane, the sonic waves will be transmitted to microphones on the flight deck. If they propagate through air, we roughly know the speed of the wave. If they propogate through an aluminum or composite skin, they will move faster. Assuming they make it into a flight deck microphone, that information now has to get through all the wiring to the recorders in the back, does it not?"

Of course we could debate the propagation rate of waves though a standard atmosphere or other materials caused by various stimuli, but AuraFlyer has convinced me not to discuss such things in this forum. I agree with his/her advice.

So all I was saying is that time interval is longer than the time it would take to sever the return wiring; but severing the wiring might in and of itself produce an electric impulse which would register and be saved in the last milliseconds of the solid state memory.

To postulate beyond that is above my pay grade. :cool:

andrasz

7th Nov 2015, 05:12

@wonkazoo

Your post (http://www.pprune.org/rumours-news/569907-breaking-news-airliner-missing-within-egyptian-fir-75.html#post9172441) is one of the more enlightened and informative ones on this wild thread, welcome to the forum.

A couple of observations to supplement yours, which changes the conclusion somewhat.

Yes, the top of the fuselage certainly failed in tension, implying a downward motion of the tail. However no HS failure is needed to explain this. The HS exerts a continuous downward pressure (it is in effect an upside down wing) on the rear fuselage to pivot the nose (and the wing) up around the centre of lift (the centre of gravity MUST be ahead of the centre of lift on all conventional fixed-wing aircraft in flight). The fuselage is a cylindrical metal tube which is very resistant to torsional forces, but as soon as any part loses its integrity it will crumple and yield to bending force very rapidly. So if the lower part of the rear fuselage loses structural integrity the tail will bend downwards before tension in the surviving upper section causes it to part. This downward pivot of the tail also places the HS vertically into the slipstream, causing its failure due to aerodynamic loads (as can be clearly demonstrated on the recovered left HS). We do not know how the right HS failed, but the damage suggests that it was ripped away downward together with the support structure sometime after the left HS was lost

The visible VS damage is consistent with ground impact at a near vertical attitude, should that kind of damage occurred while in the air in the initial breakup sequence, the VS would have been completely shorn off. The rudder and much of the trailing edge were lost in the air during the breakup or subsequent fall.

The tail and APU cone were found within 350 metres of each other (both marked and identifiable on the satellite photo when comparing larger ground features from the aerial video shown). We do not know the location of the HS, but based on the fact that photos only appeared a day later when the search area was expanded, it may be assumed to lie some distance from the tail. This implies that the tail and APU remained joined for some time after the HS has departed, which is entirely conceivable as the upper part of the joining frame is relatively undamaged on both sides.

All in all this would suggest that the initial failure occurred in the lower rear fuselage, and not in the tail section (as I have myself suggested until the HS video screencap was released).

andrasz

7th Nov 2015, 05:19

@ To everyone drawing conclusions from the CVR

Yesterday it was stated that the CVR (which appears relatively unscratched on the photos) is 'damaged' and 'will need additional work' to read out the data.

Today all of a sudden we are hearing that the last second of the CVR contains a loud sound consistent with an explosion on board (wow, that was difficult to figure out)

Yeah, right...

So far every 'official' statement made by the Egyptian investigators was followed by a totally contradicting one within 24 hours. Having lived and worked in that fine land, I know enough not believe even what they ask...

b1lanc

7th Nov 2015, 06:06

The ISIS who released the video also announced that they would let the world know shortly how they did this. Post the video they have remianed silent. This seems contrary to what the purpose of such a bombing would serve in their convoluted minds. Having not heard a peep out of them seems to indicate they were but hot air with their claims. if this was their eureka moment to claim fame with their leadership i am sure we would have heard more about it. Not discounting a human aspect to this but it also could be the act of one de ranged individual who boarded the aircraft with nothing more than a personal agenda.

Not necessarily - the success of the deed and the option to use the same procedure again may have changed some minds. Recall the underwear bomber - determined to have sufficient explosive to bring an aircraft down but couldn't properly get the 'fuse lit'. So added security procedures were implemented. That became a use once throw away tactic. If it ain't broke don't fix it.

Edit: Maybe I'm thinking of the shoe bomber.

wonkazoo

7th Nov 2015, 06:08

Thanks for the kind words.

I originally envisioned a scenario like you describe with the tail collapsing downward, and that may still be the operative way that it failed. (Remember- we're all speculating with limited information!!) My reasoning for discounting that evolution are based on the following:

1. When the airplane isn't flying- I.E. when it is sitting on the ground, there is little or no stress from gravity. This effect functionally must be the same in flight, which is why it seems likely that aerodynamic forces were the cause of the failure at the aft bulkhead, as opposed to a resultant of the failure. Yes the HS is at a negative angle of attack- which is why a catastrophic failure of the forward attach point or jackscrew would result in a downward movement of the leading edge of the stab.

2. The CVR recording apparently ended with a bang right at the point of the failure (or tenths of a second later) which would be explained by the failure of the HS, the fracture of the fuselage, and the resultant departure of the tail- all of which would have happened in a few moments at the longest. A failure further forward moving rearward into the tail section seems more likely to take a more significant amount of time (as in seconds) then the previous scenario.

3. The posit that the explosion took out a wiring loom is impractical for a huge variety or reasons. I'm not saying it couldn't happen, just that it is extremely, extremely unlikely. It seems evident (to me at least) that the boxes were separated from the aircraft nearly instantly from the moment of failure.

The one thing I will say- and it is only an opinion, is that the hyperbolic response to the "bombing" of the plane seems really premature, and based on everything I'm seeing so far there is far more evidence to support a structurally catastrophic failure as opposed to a bomb. So despite the fact that I am arguing against the combined governments of the US, UK, and Russia, I'm a long way from having been shown anything remotely suggestive of a bomb. (Other than anonymously sourced suggestions with no evidence that an ISIL group called the mother ship to proudly declare that they bombed the plane- which is as self-serving and hence unlikely a valid source of real intelligence as I can imagine.)

Anyway it will be interesting to see where this goes.

Regards,
dce

207592

7th Nov 2015, 06:20

wonkazoo

7th Nov 2015, 06:33

@ andrasz (http://www.pprune.org/members/279483-andrasz)

One other note- that supports your theory on how it failed: If you look very carefully at the video when it is zoomed in on the topmost section of the failed bulkhead there are two fairly small outwardly bent or flared sections. They appear to be just a couple of inches (5cm) in size and do not appear to have been caused as a part of the failure as they appear to be under the lapped joint that failed. I have thought about them a great deal but have yet to come up with a plausible explanation for what caused them. (They are too small and abrupt to have been caused by the airflow itself, and they would have been protected from a direct hit until the entire tail came off.)

I'm totally making stuff up now, but if that were the point of failure it would explain the zippered tension failure down both sides- the rotation downward of the tail, and the subsequent breakup. If the rotation occurred quickly enough it could also (just maybe) explain the immediate cutout of the CVR- which we are only taking at face value right now as none of us has heard the recording...

But I have a problem with the pressure hull failing like that in that place- it seems incredibly unlikely- as does a catastrophic failure of the jackscrew assembly or the hinge point on the HS.

Bottom line is we don't have enough data to say with any certainty what the sequence of failure was- which sucks because I hate puzzles I cannot solve!! (But what we do see and know still argues pretty forcefully for a structural failure over a bomb...)

Regards,
dce

thcrozier

7th Nov 2015, 06:42

I'm afraid I don't agree.

Now the interesting part starts. i.e. How was it allowed to happen? The politics of conflict and the strategies and tactics that develop from them are far more interesting than engineering - the problems of which have mostly been solved.

The future of aviation safety primarily hinges upon identifying security breaches before they happen. Just knowing how to pilot the things is no longer enough.

Machinbird

7th Nov 2015, 06:44

Now that it has been admitted that the aircraft was downed by a bomb, and another "dodged" a rocket a month ago, should this rumour machine now be decommissioned, with thanks to all those potential AAIB Inspectors who contributed?
207592, you are free to not observe this thread if it bothers you.
FWIW, I do not agree with your statements. Nothing is proven yet other than we have a pile of aircraft wreckage and 214 lost lives :(.

AlphaZuluRomeo

7th Nov 2015, 06:59

According to the source quoted by Agence France-Presse, the debris photos show that some are riddled with [impacts - shrapnel?] [going] from the inside [towards] the outside of the [aircraft] - which supports the theory of a pyrotechnical device.
Yeah, well, "the debris photos" is the important part i.e. whoever the source is, he has no access to the crash site and his "analysis" is the same as done here ; he's obviously speaking about the starboard rear door and/or the part of fuselage punctured (most certainly by a seats rail).
Not conclusive at all. Just chatter, round and round.:zzz:

Marodeur

7th Nov 2015, 07:14

May I add my support for not closing this thread.

As is the case with all public forums, if you don't like it don't read it. The vast amount of detail and submissions posted here have contributed much to a better understanding of this scourge of our time - the wilful and sometimes pre-meditated destruction of airliners.

The quest for knowledge continues ....

Council Van

7th Nov 2015, 07:19

Time and the crash investigation team will reveal why this aircraft came down, not speculation.

If this was an Isis planted device that brought the aircraft down then why are they keeping so quite about it?

Perhaps it could have been a group or individual who are sympathetic to ISIS operating without the backing of the leaders of ISIS who are now perhaps a little bit concerned that the wrath of Putin and the Russians will come down on them.

ISIS describe themselves as fighting a war, they may have just got their wish.

HarryMann

7th Nov 2015, 07:20

kokpit

7th Nov 2015, 07:21

Oleostrut: The first video released was a fake. It showed a DC9 that crashed in the Congo 8 years ago (or so).

Are you sure, I can't find any evidence to support that, do you have a link?

oldchina

7th Nov 2015, 07:39

"My money is still on the tail strike incident. I imagine a charter plane would be treated in a similar manner as a courtesy car would be. Maintained to the bare minimum/legal requirement and slightly lax care/consideration for it"

You could not be more wrong. At the time of the tailstrike the plane was owned by ILFC. Lessors are known to be very strict when it comes to return conditions. They want it back in at least as good condition as when it went out.

theron

7th Nov 2015, 07:41

I was considering that one or both of the recorders may have stopped receiving data after the tail departed rather than in the moment of any supposed explosion.

andrasz

7th Nov 2015, 07:48

after the tail departed rather than in the moment of any supposed explosion

It is unlikely that the difference between the two would be measurable in anything but milliseconds. Also the cables to the recorders run to my best knowledge along the underside of the cabin floor, and would be among the first to be severed if the lower rear fuselage disintegrates, as is the most likely scenario.

kokpit

7th Nov 2015, 07:53

With this: http://img1.gtimg.com/digi/pics/hv1/74/206/1303/84780179.jpg

It would appear you most certainly can, and with a simple bridge camera, with the aircraft allegedly at 38,000:

https://www.youtube.com/watch?v=nu18uDHzMzA

How does this support or dispel the YouTube video of the incident?

gcal

7th Nov 2015, 07:54

@HarryMan

CCTV all over the place? On a minimum time turn around there is more than enough already to occupy the flight crew.

Pontius Navigator

7th Nov 2015, 08:07

Are we sure that an explosive decompression has an explosive sound? Having experienced bang chambers I don't recall particularly loud noises. Of course that could be a function of scale. It can also be a function of the low speed of sound at low pressures. Mind you, I have not experienced a bang from 8,000 feet.

Regarding passenger unaccompanied baggage. I submit that this is a regular event. Consider how often your luggage fails to arrive with you? It usually arrives a day or more later.

Now it is clearly impossible for a passenger to plan this but not impossible for someone to tamper with it while it is air side. Remember the nickname of Thiefrow years ago?

spinex

7th Nov 2015, 08:18

It would appear you most certainly can, and with a simple bridge camera, with the aircraft allegedly at 38,000:

https://www.youtube.com/watch?v=nu18uDHzMzA

How does this support or dispel the YouTube video of the incident?

Neither I'd suggest, several posters with more expertise than me in video editing have pointed out that the pattern of movement in the Isis videos is strange and advanced the opinion that the video(s) is a composite and a poor one at that.

StopDropRoll

7th Nov 2015, 08:23

https://youtube.com/watch?v=Fi1_1l7M8FA

Should sound something like this, even if a charge was used.

Council Van

7th Nov 2015, 08:26

Pontius Navigator mentioned unaccompanied baggage turning up a day or 2 later.

This is a regular occurrence, known as rush bags they undergo additional security measures before being carried, supposedly. I am confident in taking these from UK airports down route you have to trust the rules are being followed and your company security people have done their homework on your destination airport.

susier

7th Nov 2015, 08:32

Regarding the seating plan as depicted in post #1496 by Etud lAvia and accompanying comment;

In a previously posted image of a group of three seats, which was a still taken from a Russian video of the crash site, it appeared that only the seat to the furthest left (if facing forward) of the group was affected by multiple small holes in the seat back.

Were this to be the group DEF in row 37, to the rear of the cabin and just forward of the lavatories &c, it would only be this seat, marked in yellow (D37) whose back section would be directly exposed to the area aft of the seats, as the other two in the group have seats behind them (row 38).

Might this be relevant, considering the similar appearing damage to the R4 door top panel?

http://avia.pro/sites/default/files/pictures/ural_airbus_a3211.jpg

NB Regarding Kulverstukas' remark that this is a Ural airlines plan - it was from the article first linked to in your post, but that isn't your fault if the website has used the wrong image - does anyone have a seating plan for the airliner in question? Thank you.

dsc810

7th Nov 2015, 08:44

for what its worth....and slightly off topic
Paragraph right at the end of this D.Telegraph article saying that KLM is now only accepting hand luggage on flights out of Cairo.
British flights grounded after Sharm airport CCTV showed security lapses - Telegraph (http://www.telegraph.co.uk/news/worldnews/africaandindianocean/egypt/11980903/British-flights-grounded-after-Sharm-airport-CCTV-showed-security-lapses.html)

Pontius Navigator

7th Nov 2015, 08:49

Kopit, you don't even need that. My old video camera had a x700 zoom and a cheap Kodak has x16 optical and I know not what digital.

A key element in long distance photography is ambient light and visibility. If there is no atmospheric dust then light conditions would be excellent. I don't know what conditions are like there. I know it can vary from heavy dust to Crystal clear. Looking at the photos it looks more likely the latter.

Kulverstukas

7th Nov 2015, 08:53

This seating plan is from Ural Airlines not Metrojet/Kolavia. (susier, it's why I don't post it here yesterday, because I trying to check ;) and main reason for doubt was that I read from guy flying at this plane recently that is has only two loo in rear)

You can check image link even... :ugh:

ettore

7th Nov 2015, 08:54

Security checks are obviously an issue, but overall security in the Sinai too. It's a war zone, therefore hazardous, even if in that very incident the A/C wasn't targeted by the Egyptian miltary.

Sharm el-Sheikh flight from Stansted dodged missile in August | UK news | The Guardian (http://www.theguardian.com/uk-news/2015/nov/06/missed-by-a-1000-feet-how-british-holidaymakers-came-close-to-being-hit-by-a-missile-in-august)

mm43

7th Nov 2015, 09:11

@sopwithnz

I suggest that you give up on your quest to validate the said video(s). Firstly, the aircraft was flying in a NNW'ly direction and the sun was rising in the east. The lighting is all wrong; it should becoming from the right and below.

There is no need to go into any of the other problems - just accept that it is not "exemplar".

KaptinK

7th Nov 2015, 09:13

@kokpit: videoing an aircraft 6 miles up is one thing. Positioning yourself directly underneath said aircraft just as a planted bomb explodes so you can video it is quite another.

Mr Optimistic

7th Nov 2015, 09:14

If the recording channels have sufficient bandwidth such that the rise time of the received signal isn't characterised by limited channel response, the difference between a 'pyrotechnic' and decompression event will be very clear.

From all the discussion here, I didn't see anything clear about the separation of the rudder and HS. Is it possible for aerodynamic loads alone to shear these off if at an adverse attitude to airflow?

Pax only.

PashaF

7th Nov 2015, 09:14

Eh, i politely want to remind that even if it were any explosion, it didn't give us the cause of the crash, only the initial event.
For example, this event could not lead to the loss of the aircraft itself, but, trigger some structural failure that would not occur on another vessel. Weakened tail theories?

Bertie Bonkers

7th Nov 2015, 09:19

Quick point re this - the alleged ISIS video shows what appears to be an explosion at the centre fuel tank followed by a trail of black smoke as the plane flies on with the tail still attached (no sign of any large parts detaching from aircraft). The VS section debris on the ground shows no sign of the heavy sooting I would expect if the video were genuine.

I'm still more inclined to it being video game footage filmed from a flat screen tv with a mobile phone - game graphics really are that good these days.

Kulverstukas

7th Nov 2015, 09:36

For question about ACT fitted, it was fitted on 3 of 321 planes in their fleet

http://cdn.aviaforum.ru/images/2015/11/721434_c81846ac944f1b9d46c73f5011655409.png

http://aviaforum.ru/attachments/upload_2015-11-7_13-29-29-png.500349/

Solar

7th Nov 2015, 09:44

With all this speculation over checked baggage security or lack of, are we going to see an increase in airlines refusing to carry hold baggage or increasing the passenger fares to cover additional security checks for hold baggage.
We have all experienced the increased delays and such with carry on bags so I assume that now that the hold bag security is in doubt it would be a natural progression.
What level of security is hold baggage subjected to normally? By this I mean at the likes of LHR and most European departures. I'm assuming that it is at least X-rayed.
I know that I have had my hold luggage opened on a regular basis in the US but not that I know of in Europe.
I'm also aware of the lax hold bags security in a lot of shall we say non western airports.
If this is proven to be a bomb concealed in hold baggage flying will really become more of a heartache than presently.

Kulverstukas

7th Nov 2015, 09:46

Another sad picture...

http://i.imgur.com/fcvWeiD.jpg

ILS27LEFT

7th Nov 2015, 09:48

I have seen many videos that look clearly fake whilst in fact they are instead genuine. Poor quality and in some cases inflated post video enhancements can confuse us, nobody has officially confirmed that the ISIS video of this incident is 100% fake. Many experts have said that it is the wrong aircraft type, which is not the case in my opinion: I see the correct aircraft type and the location of explosion on aircraft seems to coincide with latest developments from the investigation Teams and info passed to governments by intelligence agencies, e.g. burnt bodies sitting at the rear, explosive device in hold etc.
Do you remember the ATR72 crash video in Taiwan?... this video also looked fake for various reasons but it is 100% genuine. Unprofessional but genuine.
Definitely the ISIS video is very badly made, it is unprofessional and possibly full of post-video editing enhancements but the video itself might contain the "artificially enhanced" images of this incident. Previous posts have explained why video timing could be an easy win for those on the ground.
The fact remains that if we combine the ISIS video with the recent developments it is too much of a coincidence that everything seems to match. A very unprofessional video does not mean fake. It could easily be a genuine video that has been very badly edited for propaganda purposes.
Those who made the video also stated that "they 'brought down' the plane on the first anniversary of the Sinai group's signed allegiance to Isis/Daesh":mad: which cannot be another coincidence as the anniversary date seems to be in fact correct.:mad:

hamster3null

7th Nov 2015, 09:48

Thanks Pontius Navigator. I realise that video's have a hellish zoom, but initially I was really sceptical that someone could video an aircraft at cruise altitude from the ground.

This was one of my reasons for doubting the 'video of the event'.

I was discounting any electronic zoom, as that typically degrades the end result too much, but the camera in the example has a 500 optical zoom.

However, it seems it certainly can be done, but judging by the very small number of results through Google, I suspect it isn't something that is easy or often brings about the desired results.

I played with this last evening. Using a 6 inch telescope, I can see airliners flying at cruise altitude 30-40 miles away, in better quality than the alleged ISIS video. I can even take pictures directly through the eyepiece using a cell phone. The tricky part is tracking the aircraft, since, at that zoom level, they cross the field of view in mere seconds, especially if they are flying perpendicular to line of sight. And taking pictures would require either a helper or some way to hold the phone/camera in place.

I'll try the same tomorrow with a DSLR camera and a camera-telescope adapter.

GroundedSpanner

7th Nov 2015, 09:55

oldchina wrote:
Lessors are known to be very strict when it comes to return conditions. They want it back in at least as good condition as when it went out.

Edit - the following rant is NOT directed at the lessor of this AC - ILFC/Aercap are in my experience one of the better lessors in the business.

AC Lessors are not in the airplane business, they are in the money business. They just happen to get their money from aircraft.
Lessors only want one thing, that their asset is earning revenue for them.

If there will be a gap between end of lease with one customer, and start with another, then indeed they can be very picky over the state of the AC and its records on return. If the Lessor can find fault with the AC or records then it means they are still getting rent and very lucrative penalty payments from the lessee until the aircraft is up to spec.

On the other hand, if the lessee is a bankrupt airline then the lessor wants their asset back, they will just take it. Or if the lessor has a customer waiting for the AC, they will attempt to handle their requirements as quickly and cheaply as possible. They will try to palm off any old :mad: on to the new lessee, to get the asset earning rent again. When leasing out an AC the lessor will indeed only do the absolute bare minimum required, using the cheapest maintenance facilities and cheapest parts. Maintenance standards mean nothing to them, its all about stamps on paper to show legal compliance. If the aircraft does crash, the airline takes the rap, and the lessor gets a big fat insurance cheque for the value of the lost asset and lost future rent.

I personally don't believe in the structural failure hypothesis for this incident (my money is on a small device in the rear cargo hold, setting off the additional centre tank as a fuel/air bomb, ripping apart the fuselage aft of the wing, but lets see what the investigation finds). But please, never allow yourself to believe that an aircraft lessor has a safety oriented mindset anything like we Airline Professionals have.

tatelyle

7th Nov 2015, 09:55

Daily Mail (front page) tomorrow reporting that the cockpit crew of a Thompson flight on August 23rdsaw a missile pass within 1000 ft of their aircraft whilst near SES.

Interesting that the UK CAA kept quiet about this. I have certainly not heard of it.

Thomson flight with 189 passengers dodged missile above Sharm El Sheikh | Daily Mail Online (http://www.dailymail.co.uk/news/article-3307741/Rocket-attack-UK-tour-jet.html)

One wonders what the priorities of the CAA are. I reported to the UK CAA about eau de cologne causing fires in cockpits, like the Egyptair B772 in 2011. But they would not even acknowledge my report, even when sent to the head of the CAA.

What are the CAA for, if they will not act on reports? Why do we bother with MORs?

Peamasher

7th Nov 2015, 09:59

I took this photo /www.flickr.com/photos/peamasher/6574265697/in/photolist-b1WQ9z with a Panasonic FZ-28 bridge camera which has a maximum zoom of 476 mm in 35mm film terms. The El Al B747-400 was at 35000', somewhere near Luton according to FR24, and I photographed it from my home in Aylesbury, Bucks.

On another occasion, using the camera as a telescope, I could easily read 'Emirates' on the underside of a Dublin bound B777, just south of Manchester.

Thruster763

7th Nov 2015, 10:00

A number of posters have questioned CVR/FDR locations, numbers and backup power. First issue is that this is restrained by costs. The operators will resist anything that adds to costs (this includes weight). The take up of solid state digital (soild stste is the recording medium, traditional "digital" FDRs use magnetic tape) recorders is because they are cheaper to maintain (no moving parts). With solid state digital you can easily have a combined CVR/FDR, but this "puts all your eggs in one basket". The sensible solution roposed by the regulators and used on the latest aircraft is to have two combined CVR/FDRs one at the front and one at the rear of the aircraft. This gives the best of both worlds, still only 2 recorders to pay for, better chance of one surviving and you only have to find one to get all the data. There are proposals to mandate short back-up power supplies to capture data after power loss but again it's costs, particuarly lifetime costs - batteries require maintenance- that i producing resistance. There are also proposals for cockpit video recorders, crashworthy or otherwise, but that's a whole other issue.

Kulverstukas

7th Nov 2015, 10:10

tatelyle, no it can't at least thousands of regional media and whole internet is out of control. And even last legislations about security on military casualties makes huge wave of discontent.

I deny any possibilities that if any news agency (except, may be, 1st TV channel and Vesti24) receive letter from ISIS they will not publish it immediately. I also think this two also will publish it but with caveat emptor :rolleyes:

Plastic787

7th Nov 2015, 10:20

How can anyone who has seen that "explosion" in the video POSSIBLY think that is a real video?? Do you think that the video of the aerobatic aircraft landing after its wing has fallen off is genuine too? And even that is a better quality fake than this example.

I was hoping the penny would have dropped by now but obviously it hasn't. Regardless of whether ISIS are responsible for the actual accident (and it's certainly looking possible) that video is a fake, absolutely no doubt about it. The explosion doesn't even look remotely realistic.

Pontius Navigator

7th Nov 2015, 10:29

The explosion doesn't even look remotely realistic.

And how many observers here have seen a real explosion.

The late XV105

7th Nov 2015, 10:32

I too believe the image is a fake and hope it is proven that way.

Cheap Canon SX200 compact camera with 12x zoom plus some cropping (not much as the resolution of this camera is too low).
January 1st 2012.
A380 at cruising altitude over Krnov, CZ
The original photo shown full screen clearly identifies the airline (SQ) which I then cross-checked with FR24 when back in the house (SIN-LHR I recall).

http://i1062.photobucket.com/albums/t493/PPRUNE64/JB/IMG_120101114300.jpg

Livesinafield

7th Nov 2015, 10:37

what is that picture with the notes on it all about?

Kulverstukas

7th Nov 2015, 10:40

Livesinafield , Seems pilot exams or check preparations :(

Title reads Section 1 Programme 2 Example 1 and 2 to lower the minimum.

TASK 2 30h300 200 m. TakeOff. when lowered to the SAT II, provided that the there was held 6 FPS landings at simulator for the preceding 6 month CAT-I and 1 TO in the same period with the visibility on the runway of less than 400 m ...

wanabee777

7th Nov 2015, 10:41

It appears to be notes on ILS procedures.

andrasz

7th Nov 2015, 10:46

@GroundedSpanner

Very clearly you have never ever dealt with ILFC. I have.

If anyone, THEY are in the aircraft business, more so than many of the airlines. The A330 design owes its final form (and success) to Steven Udvar-Hazy who told them that they either build it to his specs, or he will not buy any. They were elbow deep in the 787/350 design process as well, being one of the largest customers for aircraft manufacturers.

ILFC would have supervised that repair very carefully, more so than the operating airline. That being said, flaws can remain no matter how carefully the repair was planned and supervised.

andrasz

7th Nov 2015, 10:56

For question about ACT fitted...

Many thanks, that's about the most relevant piece of firm new information to surface in the past 2-3 days. Clearly C/N 663 had an ACT fitted, that would much better explain the in-flight fire despite the seemingly intact wings and center section.

Plastic787

7th Nov 2015, 10:58

Pontus Navigator so you need to have seen something in real life now to know if it is real or not? By that logic when I went to watch FC Barcelona play last year I never should have recognised Lionel Messi or Luis Suarez because I'd never seen them in the flesh before.

I've seen video footage of plenty of "real" explosions thanks, just as I've seen my share of CGI ones to compare them with. I happen to recognise the difference, especially when the light sources and shadows and propagation are all wrong.

ettore

7th Nov 2015, 11:17

Former Ben Gurion security chief (http://www.cracked.com/blog/7-reasons-tsa-sucks-a-security-experts-perspective/), Rafi Sela (http://www.ar-challenges.com/inpage.asp?page_id=200&curr_id=200&pa=200), gave an interview to the Swiss German News portal Watson (https://www.watson.ch/International/Luftfahrt/767536493-Ex-Sicherheitschef-des-Flughafens-Tel-Aviv--%C2%ABEs-ist-sehr-einfach--eine-Bombe-an-Bord-zu-schmuggeln-%E2%80%93-nicht-nur-in-%C3%84gypten%C2%BB), making the following points (in German) :

a) no engine explosion

b) smuggling a bomb on board is incredibly easy, in the U.S. too (http://abcnews.go.com/US/exclusive-undercover-dhs-tests-find-widespread-security-failures/story?id=31434881)

c) there is no hope checking efficiently cabin bags

d) better check pax and airport employees behaviour

e) cameras and computers can sort out 80% of the people having access to the A/C

f) halting, searching and asking the 20% remaining brings more results than shoeless pax or forbidding a more than 50 ml bootle of water

The interview (https://www.watson.ch/International/Luftfahrt/767536493-Ex-Sicherheitschef-des-Flughafens-Tel-Aviv--%C2%ABEs-ist-sehr-einfach--eine-Bombe-an-Bord-zu-schmuggeln-%E2%80%93-nicht-nur-in-%C3%84gypten%C2%BB) might be biased because Rafi Sela earns his living in the security business, but it's worth reading if you can do it in German.

ILS27LEFT

7th Nov 2015, 11:30

Video was released very shortly after the incident, very little information was available to the public including to ISIS in the Sinai Province when video was released.
The video could therefore be genuine, maybe we will never know, it does not matter, some facts: officially, when the video was initially released, the authorities discounted the fact that the plane was shot down by a missile but the original message from ISIS did not mention a missile at all, some translations were in fact incorrect, I understand the exact translation is the one below which could indicate a bomb (and not a missile) as it seems to be now the official cause; this means that officially the video has not been declared fake by anybody. It could be indeed very genuine.
In any case the video will not change the fact that this was very likely a bomb in the cargo hold. Very likely bomb was planted by somebody with easy access to the aircraft who was not on board. If a £20 note can let you completely bypass security checks at that airport (proven) imagine what £1,000 can do. Easy, easy, easy.
Message from ISIS was later re-translated as follows (no mention of missile):
“Soldiers of the Caliphate were able to bring down a Russian plane above Sinai Province with at least 220 Russian crusaders aboard. They were all killed, praise be to God. O Russians, you and your allies take note that you are not safe in Muslims lands or their skies.”

“The killing of dozens daily in Syria with bombs from your planes will bring woe to you. Just as you are killing others, you too will be killed, God willing.”

:mad:

Pontius Navigator

7th Nov 2015, 11:35

Plastic, I didn't say real-life with you present at the scene but that you had seen genuine explosions as I think many people will be influenced by the Hollywood version where Harrison Ford can out run the fire front.

I was of course questioning your experience.

I just looked at that explosion again and would not like to assert that it was fake. Fireball development was uniform, rapid, and circular as you would expect where there is no tamper. Its duration is also consistent.

What you cannot confirm from the video is that it was not a composite image. Slow speed analysis would show its development.

Old Boeing Driver

7th Nov 2015, 11:41

I'm not smart enough to figure out whether the video is real or not.

However, the question of the timing and placement to get the video may not be as complicated as one might think.

How does anyone know that one of the passengers may have been a suicide bomber. He/She may have been instructed to push "the button" at a precise time.

I am assuming that this flight route may have a fairly regular track, so once takeoff time was known, it would have been fairly easy to have videographers, maybe multiple, in the right locations.

Just my $.02....

Mr Optimistic

7th Nov 2015, 11:44

There could well be some teenager with a video editor out there sniggering at this discussion. Too much black smoke, unburnt carbon, much too quickly. Reason the video doesn't lovingly show the descent ? Fake would become obvious.

San Diego kid

7th Nov 2015, 11:45

To this point, I still have not seen any evidence in the pictures we have for a bomb exploding, and more for a failing HS imho.
Also, the video is fake, very easy to make in a video game and film from the screen.
A lot of hear say and false flags till now, where all parties leaking info need another outcome to look good or gain some political advantace.

ettore

7th Nov 2015, 11:45

@Pontius

According to Rafi Sela interview in Watson (https://www.watson.ch/International/Luftfahrt/767536493-Ex-Sicherheitschef-des-Flughafens-Tel-Aviv--%C2%ABEs-ist-sehr-einfach--eine-Bombe-an-Bord-zu-schmuggeln-%E2%80%93-nicht-nur-in-%C3%84gypten%C2%BB) (my previous post), El Al never carry pax and cargo on a same plane. Could be a source of inspiration for more security (and more flying) ahead.

Kulverstukas

7th Nov 2015, 11:50

Makes assumption on involvement of ISIS on base that they claim that "Russia will regret" is not too smart. I can remind you:

1) 2015-10-09 Vladimir Putin will lose the support of his people, when Russian troops will begin to suffer losses in Syria, according to a former US military general Mark Hёrtling. However, he noted that the long wait is not necessary: according to him, have already begun to appear reports of downed Russian helicopters and destroy tanks.

2) BRUSSELS, October 8 - RIA Novosti, Natalia Dobrovol'skaya. US Secretary of Defense Ashton Carter said that the actions of Russia in Syria will have consequences for Russia itself.

"It (Russia's actions in Syria) will have implications for Russia", - said the head of Pentagon reporters in Brussels. "I also expect that in the next few days the Russians will suffer in Syria", - he added.

But I hope it doesn't mean that US was involved in bombing ;)

dmba

7th Nov 2015, 11:52

I'd be shocked if that video is not a fake. How does one explain the background sky colour changing? if you follow the colour of the sky behind the aircraft, it switches from blue to grey and brown, as if the angle of the video is changing drastically in height, which it wouldn't do if someone was filming from the ground. Looks like total rubbish to me.

Mr Optimistic

7th Nov 2015, 11:53

Not to mention the 400+ KT airstream.

oleostrut

7th Nov 2015, 11:55

"I am assuming that this flight route may have a fairly regular track, so once takeoff time was known, it would have been fairly easy to have videographers, maybe multiple, in the right locations."

We are not the only ones that know about the flight tracker sites. In the last 10 years, terrorists have become very tech savvy concerning the internet .

Old Boeing Driver

7th Nov 2015, 12:02

I suspect that no matter who caused the bombing (if confirmed), that ISIS will be blamed.

Sober Lark

7th Nov 2015, 12:05

Security checks
Just like pilots or operators, perhaps passengers should be able to 'report occurrences' when they notice lax airport security that is of concern? Some type of online 'report' form could be considered.

slats11

7th Nov 2015, 12:07

There is some disagreement here whether the video is genuine or not.

Consider this however.

The video clearly shows an explosion around the aft fuselage of the aircraft. There is too much smoke for a simple bomb - there must have been substantial combustion. Furthermore the wings and everything forward remained intact. And the plane kept flying relatively unaffected for at least some time.

This video was released within 24 hours of the crash, before non-involved parties could have known any details. There was no claim of a missile - that seems to have been assumed in early reports. There was just a claim of "brought down" or "bring down."

Our current understanding of the crash is an explosion in the aft fuselage. In a plane with an aft centre tank. And the plane appears to have flown on on for some distance. And the wings and the forward fuselage appear to have come down relatively in one piece.

People have speculated it is the wrong aircraft and the combustion was an engine fire on a DC9 or similar (i.e. rear mounted engines). Would not the sudden loss of an engine cause significant yaw?

Plus no one has been able to find another source of this footage.

Sometimes 2+2 does equal 4

andrasz

7th Nov 2015, 12:11

@ GroundSpanner

With that qualification, I agree. I have dealt directly with some of those shady characters. My favorite one was the guy who, on being confronted with the query that I've heard the company he is representing went out of business a few weeks earlier under somewhat suspect circumstances, did not even blink just pulled another business card from his pocket while attempting to pull the one already in front of me on the table...

That being said, I think we can all agree that if ILFC supervised that repair and it was done at Toulouse, it is likely to have been up to the proper standards. In any case, short of a RPB rupture which clearly was not the case here, a fatigue crack of the skin or one of the frames due to damage / improper repair decades earlier is very unlikely to cause an instant disintegration as we saw here. The Aloha cabrio could even land in one piece.

Kulverstukas

7th Nov 2015, 12:11

Just to remind about "tighter security at airport" last two suicide bombing in RF was done right at the queues to metal detector frames (DME and Volgograd).

Kulverstukas

7th Nov 2015, 12:17

A0283

7th Nov 2015, 12:22

Ahead of a long awaited and probably due Egyptian press conference:

Still missing the THS, centerbox of vertical stab, any part of the rudder, 3 cargo doors, some pax doors, a number of fuselage panels (windows), ... and that's only talking about the 'outside' and only about the major components. Even when accepting that a significant part of the fuselage has been destroyed by impact and subsequent fire.

Till now, as far as i have seen, zero CLEAR evidence of any intentional explosion or exploding device. Good evidence would require far better pictures. And real evidence would go down to the micro level.

There is a big difference between a loud sound and an explosion. And explosions can be, amongst others, classed as structural (failures related) and bombs (or missiles or explosives or ...).
Good evidence requires a real description or soundfile of the sound. And real evidence requires spectral analysis.

So how anybody can think, at this stage, with that lack of evidence, and lack of information, that everything is solved is beyond me. There will be serious questions even after the press conference today, after a preliminary report and even after the final report. As far as i know, cases are never fully closed (ref for example the 737 rudder cases). Airplanes and the aerospace system are complex, there are no single and easy answers. We are looking for a chain of events with multiple elements and a lot of possible interaction or single action relations.

Hope for a good and clear press conference. Including information how the investigation will proceed. And if the prio becomes a criminal one, some information on how the safety one will be handled.
+++
With the present state of the CVR (SSMCVR) and FDR (...) - it would be very interesting to hear something about the condition of the QAR, maintenance recorders and the like. From the few pictures that we have the racks and boxes looked rather good.

Jet Jockey A4

7th Nov 2015, 12:32

Quote:

Selon la source citée par l'Agence France-Presse, les photos des débris montrent que certains sont criblés d'impacts allant de l'intérieur vers l'extérieur de l'appareil, « ce qui accrédite plutôt la thèse d'un engin pyrotechnique ».

My translation:
The source* cited by AFP expressed that the photos of debris had certain impact damages on the interior versus the exterior of the airframe << that very well could credit the hypothesis of a pyrotechnic event** >>.

*in context, this source seems to be the same source cited earlier, I made a translation of that a few pages ago.

**engin can mean both "engine" and "method by which something is driven/propulsed in the wanted direction"

Your wording is not totally correct in its translation. I will try to be a bit more precise in my wording...

débris montrent que certains sont sont criblés d'impacts allant de l'intérieur vers l'extérieur de l'appareil,

My translation... "debris show that some are riddled with impacts going from the interior to the exterior of the aircraft"

ettore

7th Nov 2015, 13:03

@Kulverstukas

Just to remind about "tighter security at airport" last two suicide bombing in RF was done right at the queues to metal detector frames (DME and Volgograd).

That's why the focus should be set on observing the behaviour of pax and airport employees instead of spending senseless amounts of money on useless hardware.

andrasz

7th Nov 2015, 13:18

@ ettore

Amen to that.

Kulverstukas

7th Nov 2015, 13:26

ettore, just five minutes ago read big praise post at LJ about Israeli security at airports... And immediately after that one which criticized it and demonstrates how's its all is just money laundering (government subsidies stealing) :}

What I mean, it's usual standoff of armor and bullet. Also note that bullet needs only one chance of numerous to succeed (like old joke of probability to meet crocodile in the center of Moscow - it's 1/2, because you either meet it or don't) and at the same time armor which prevents other 999 of bullets will be treated as failed.

slats11

7th Nov 2015, 13:36

slats, for me timeline look like that:

1) Info about plane lost
2) Info that crash site was found
3) First photos in the press and at the forums
4) ISIS claim (just banner with some Arabic posted)
5) More photos and info that plane was destroyed at altitude and that there definitely was fire ant that tail separates
6) Video posted with comments "plane was shut down by us", quite quickly removed
7) Agreement that there was no traces of any missile
7) Video posted again with "we did it but we will not tell you how"

Am I wrong?

I'm not sure there was any claim the plane was shot down. I think this was an assumption that got incorporated into media reports. I may be wrong however.

Also, it would not be surprising if ISIS had a generic banner prepared in advance, and followed with the actual recording a short period later.

So I'm not sure the above sequence of events makes it less likely to be genuine.

We may just have to wait and see - time will likely tell if it is genuine or not.

If this video is true, what will Joe Public think? I believe he will think "These guys can bomb a plane with such reliability they can pre-position someone to record it." That is a pretty frightening thought.

As such, if it is true then don't expect our leaders to confirm its legitimacy.

Conversely I believe our leaders would have been quick to denounce it as a fake if they could. We would have been referred to the real incident. Or we would have graphics experts telling us it was computer generated and why.

In this case, the silence is deafening and (to me) suggests it is accepted as genuine.

Mr Optimistic

7th Nov 2015, 13:45

Well to me it is obviously not realistic in this scenario. Looks like the smoke plume from a relatively low temperature fire in slow air. Wasn't time for this to develop and lateral width of plume much too large for injection into fast airstream. Try blowing smoke out of your car window at 60 mph.

Kulverstukas

7th Nov 2015, 13:45

slats, there also can be that it was bombing but this video is fake, isn't it?

As for government, right way of action is treat any information as not true until contrary will be positively confirmed and act in precaution measures as if any information is true until contrary will be proven. Right?

HarryMann

7th Nov 2015, 13:52

HarryMann

7th Nov 2015, 13:54

Makes assumption on involvement of ISIS on base that they claim that "Russia will regret" is not too smart. I can remind you:

But I hope it doesn't mean that US was involved in bombing ;)

Why on earth would you say that.. ?
It's like saying Holland or Malaysia did it as retribution for MH17

RYFQB

7th Nov 2015, 13:57

"These guys can bomb a plane with such reliability they can pre-position someone to record it." That is a pretty frightening thought.
These guys also specialise in putting their horrific deeds on display, don't they? How come they accomplished all this, yet didn't bother with a tripod and proper camera, so they could show us in glorious HD? Track the plane for a minute or so and show us people falling? It's too much of a squandered opportunity, imho.

slats11

7th Nov 2015, 13:58

slats, there also can be that it was bombing but this video is fake, isn't it?

Sure. Could be.

But ISIS currently have a reputation that all recordings have been genuine and they have always performed whatever atrocity they have released video of. I suspect ISIS value that reputation.

That reputation takes a hit if this is a fake.

Kulverstukas

7th Nov 2015, 14:00

HarryMann, mods are working fast, but I read at least dozen posts in this thread that this accident is revenge for MH17

Gertrude the Wombat

7th Nov 2015, 14:00

It's like saying Holland or Malaysia did it as retribution for MH17
There is of course a precedent for relatives of victims taking revenge after an airliner has crashed:

https://en.wikipedia.org/wiki/Vitaly_Kaloyev

Kulverstukas

7th Nov 2015, 14:02

But ISIS currently have a reputation that all recordings have been genuine

Really? Or so your media want's you to believe?

Kulverstukas

7th Nov 2015, 14:06

There is of course a precedent for relatives of victims taking revenge after an airliner has crashed:

Except that case was investigated and guilty was found if not punished in scale this poor guy seems appropriate. Also why plural? This poor guy acted alone.

jxf63

7th Nov 2015, 14:06

Of course, the famous video could be genuine AND fake...

One can easily imagine that we see footage of the actual aircraft and the flash from the explosion, but poorly edited fake black smoke was then added.

Why ? Because it didn't look "impressive" enough :sad:

Don't forget the aircraft probably carried on flying for a while before breaking up - this might have taken it out of discernible range... Also, it may explain why no footage of the breakup and downfall...

AN2 Driver

7th Nov 2015, 14:08

Don't forget the aircraft probably carried on flying for a while before breaking up

Not according to the positions. The place radar contact was lost is pretty much on top of where the wreckage hit the ground.

_Phoenix

7th Nov 2015, 14:14

StopDropRoll, posted earlier a video of an experiment.
It shows the dynamics of an explosion inside of a real aircraft.
See in video at 3:03
https://youtu.be/Fi1_1l7M8FA?t=183
Notice the pressure gauge mounted near the cockpit. The pressure clearly increases before dropping.
The shock wave meets first the cabin pressure sensors, before to be heard in cockpit microphones(CVR). The FDR should show the cabin pressure increase.

short bus

7th Nov 2015, 14:25

ISIS of Sinai was claiming credit for this. They are the minor league of ISIS. If the ISIS HQ was fully involved in this plot, they might be expected to have better video production quality.

As for the black smoke, that is typical of an overly rich fuel mixture - more fuel than oxygen. Low O2 levels at 30k feet and a ruptured fuel tank would probably burn very sooty.

montague

7th Nov 2015, 14:26

Press conference provided little info - CVR had a "noise" at the end.

Kulverstukas

7th Nov 2015, 14:28

Press conference provided little info - CVR had a "noise" at the end.

As expected.

Egypt is checking video footage at Sharm al-Sheikh airport for any suspicious activity linked to the Russian plane crash in Sinai, officials said on Saturday, in the clearest sign yet that they believe it could have been targeted by militants.

The government has repeatedly said it would be premature to blame Islamic State fighters in Sinai for the crash, despite Western suspicions that the plane was brought down by a bomb and a claim by the Islamist militants that they were responsible.

News that officials were reviewing camera footage at the airport came shortly before investigators who have examined the plane's black boxes were due to speak about their work so far.

"We want to determine if, for instance, anyone sneaked past security officials or the metal detectors. We are also trying to determine if there was any unusual activity among policemen or airport staff," one of the officials told Reuters.

slats11

7th Nov 2015, 14:32

Press conference provided little info - CVR had a "noise" at the end.

Notable that Chief fronted the media alone. You would normally expect a panel as a gesture of consensus and cooperation.

Instead we had empty chairs and the Chief stating he did not know why others did not participate!

Perhaps there is a degree of tension within the multinational group of investigators.

A0283

7th Nov 2015, 14:32

Let me try to transcribe what has been said in english (my arabic is not good enough):

Originally announced press conference start 1700EGY time. Started 1715 EGY time.

Introduction by a gentleman ... but CNN had no sound at that moment.

Then start by Chairman Mr. Ayman al-Muqaddam ... Head of the Commission of Inquiry.

Starts with condolences.

Some explanation apparently why he was sitting there alone. But not clear to me yet (will check the recording of the press conference that i made).

Dignitaries visited on day 1 after the accident. Egyptian airforce send 5 planes with the Egyptian and international investigators to the site. Egyptian army guarded the site. Major pieces photographed by the investigators and their geo coordinates taken.

Investigators 47 plus advisors 11 to total of 58 participating.
EGY 29 + RUS 7 + EIRE 3 + FRA 6 + GER 2, + Airbus advisors 10, EASA 1 = 58 persons participating.

5 groups have been formed:
1. recorders,
2. accident site,
3. operations - crew, atc, airline information, meteorology,
4. aircraft and systems,
5. medical, forensics,
ALL groups are still in the Information Gathering Phase.

Under Egyptian Law 28, ICAO Annex 13.

Weather at the moment (today) is bad. When weather improves investigators make new visits.
Wreckage will be moved to Cairo and investigated methodically.
Aircraft wreckage will be searched for computers with non-volatile-memory.

Objectives of the investigation:

1. debris area is wide, 13km long, which suggests an inflight breakup, a number of parts are still missing, search underway for them,

2. observation ... origin of breakup still unknown,

3. recorders were recovered on Day 1, both successfully downloaded, and preliminary review performed,
FDR shows TO at UTC 03-50-06, last 04-13-20, total duration 23 min 14 sec <have to check this>,
Last ALT 30,888 ft and aircraft in CLB Mode.
Last recorded speed 281 knots.
Modes (autopilot) A/P1 engaged till the end of the recording.

4. CVR
- first listening was done,
- at the moment the team is working on the transcript,
- we note that a noise was heard in the last second,
- spectral analysis on the recording will be performed by specialized labs,
- investigators got no intelligence from other parties... if parties have info please come forward.

5. A number of media reports make suggestions with information/intelligence said to be based on official sources. The investigation team has not had access to such information. We ask parties to provide that information to the investigation.

6. ALL scenarios are still open. There are no conclusions as yet.

Image (CNN?) shown in the background altitudes 3,000 - 20,000 - 25,000 - 29,600 - 33,000 - and as stated ending 30,888 while in CLB MODE.

The Chairman read it out in clear english. Then gave time for a limited number of questions. He says he has to return to his team - read investigation.

A rather furious sounding person present (CNN says a journalist) , starts normal then increasing in anger, demanded that the chairman spoke in arabic. After some noise exchanges and happenings the chairman started reading out the same declaration in arabic.

Chairman:"... i can read in arabic...if you want..."
Chairman:"...asked other parties to come over, but they decided not to participate (A0283 - in the press conference) ... perhaps they had other ... "...

+++

Apart from the transcript above ...

First impression. Clear explanation which you expect at this stage of the investigation. Was impressed by the statement being made in english first, also understand the demand for arabic of course. But the fact that all people killed were foreign might also be called 'being sensitive' to the relatives of those killed. Shows the extreme importance of clear communications during investigations. If the chairman had said something like "out of piety i make a statement in international english first, and then repeat it in arabic", that may have calmed the mood. Have to note that the introduction of the press conference as transmitted by CNN had no sound. So i could have missed something at the start.

The press conference was clear, up to what you expect, though rather late in delivery. But the promise is made that more regular conferences will be held from now. How everybody interpretates the contents ... i leave that upto the readers.

The conference provided information on a number of issues, including missing parts and information.

Note that the chairman talked about a NOISE and did not use the word EXPLOSION.

+++

CNN now says (after the conference) - after arabic translation - original press conference would have been by EGY Minister of Aviation and a RUS representative. And only at the start of the conference it became clear that it would be the Chairman. The journalist complaining about this absence and appartenly suggestion that there was a conspiracy.

Apparently the chairman also suggested that the sound could have come from exploding Lithium batteries.

+++

montague

7th Nov 2015, 14:35

He seemed slightly bemused that they weren't there.

Also still looking for some of the wreckage

Kulverstukas

7th Nov 2015, 14:38

Notable that Chief fronted the media alone. You would normally expect a panel as a gesture of consensus and cooperation.

Nothing to tell beyond what was leaked already. No positive proof of any version yet, so no sense to participate.

slats11

7th Nov 2015, 14:41

Nothing to tell beyond what was leaked already. No positive proof of any version yet, so no sense to participate.

Solidarity is important at events like this press conference. It was conspicuous by its absence.

b1lanc

7th Nov 2015, 14:43

wanderinwilco

7th Nov 2015, 14:52

Irrespective of the actual cause of this terrible crash, ISIL have scored yet one more coup in their relentless attack on the West. At almost no financial cost to themselves they have caused major airlines to make changes which will bring misery and extra cost to thousands of everyday tourists who just want a holiday. The security ramifications (utterrly laughable if not so tragic) will linger on for years.

anartificialhorizon

7th Nov 2015, 14:58

The press conference descended into farce with a questionnaire shouting at the chief about why the statement was not read out in Arabic.

This sums up what is wrong with the world and the region in particular.

Don't they realise that everyone that died on that plane was foreign? Do they not realise that SES is completely dependent on tourism and that this is a story of worldwide interest. They are making idiots of themselves shouting why is this not in Arabic!

I have first hand experience of working with the Egyptian authorities and I am not feeling warm and fuzzy about their capability, their openness and their independence from government influence. The fact that he said " his people were waiting for him" and he couldn't take more questions is an example that they cannot just be straight and only speak in rhymes. Why not just say, that is it and I am not going to answer more questions.....He is the head investigator after all!!!!

Deliberate act, no doubt, from day one. Either an event carried out by someone onboard or a device planted. Let's ignore the stupid, amatuar video posted by IS and concentrate on the event itself.

Backoffice

7th Nov 2015, 15:08

A link to the first version of that video was posted on about page 7 of this thread on 01Nov and I saw it around 16.45.
2 posts down someone said fake, there was little or no conversation about it and the mods deleted the linked post.
I found a longer version on Youtube aired by CNN a couple of days later.
The fact it didn't appear elsewhere in the the UK media suggests some suppression methinks. :suspect:

Kulverstukas

7th Nov 2015, 15:09

Solidarity is important at events like this press conference. It was conspicuous by its absence.

In the current state of foreign affairs it's not, alas.

Kulverstukas

7th Nov 2015, 15:13

Wow, this press event was not worthless. Not every part of plane was found. FDR stops at 4:13:20.

anartificialhorizon

7th Nov 2015, 15:18

Kulverstukas.

What do you expect!? The wreckage, we are led to believe, is spread over 13kms..... And that is what they know. Of course they haven't found every piece of wreckage yet:ugh:

mickjoebill

7th Nov 2015, 15:22

And how many observers here have seen a real explosion.

Having filmed 3 airframes being blown up as well as gas, petroleum, dust explosions, flashovers and numerous controlled demolitions for science docs I have a good idea of how explosions are imaged by video cameras.

The disperancy in the black level of smoke versus the airframe is my main issue.

Yes if the video is real the smoke could have been processed separately to alter its black level for dramatic effect. But a higher priority would be to stabilise the footage.

However a common trick to help marry composite elements is to leave or make the frame wobbly.

The technical quality and editorial punch is relatively poor compared to their other propaganda, where they leave no doubt as to the authenticity of events incurring in front of the camera.

So it is out of character that they have not released any images of the aircraft falling.

Mickjoebill

Kulverstukas

7th Nov 2015, 15:23

anartificialhorizon, What do you expect!? The wreckage, we are led to believe, is spread over 13kms..... And that is what they know. Of course they haven't found every piece of wreckage yet

It is not necessary to eat the whole cake to know the taste. I read this as "we don't found any evidence yet"

Kulverstukas

7th Nov 2015, 15:27

Mickjoebill I second you in this: However a common trick to help marry composite elements is to leave or make the frame wobbly.

Also watching a lot of flying at large distance planes footage I feel this wobbling looks more artificial than real one, as operator pretend that camera is shaky. Coupled with vertical framing, to make it looks more like phone video.

Pontius Navigator

7th Nov 2015, 15:28

rog747

7th Nov 2015, 15:33

the metrojet was almost at FL310 (filed for FL360 ) on heading 351' out of SSH at 400kts

at the same time there was another Russian A321 Nordwind flight NSW1969 in the vicinity on reciprocal course 150' level at FL330 heading for SSH just 10 km ahead and to the right side of the metrojet 321 at a speed of 509kt

if the ISIS videos were true with that explosion and black smoke trail would/should the Nordwind crew and/or pax possibly have seen something?

see here
https://twitter.com/FMCnl/status/660378915496730625

that's all been very quiet on that

HarryMann

7th Nov 2015, 15:44

There is of course a precedent for relatives of victims taking revenge after an airliner has crashed:

https://en.wikipedia.org/wiki/Vitaly_Kaloyev

Mmmm... two different laws and two different cultures in that story.
Make him a hero why don't you... what if everyone bereaved went around killing the supposed culprit ?
In fact there were others much more culpable than that air traffic controller left on duty by himself...

Marodeur

7th Nov 2015, 15:45

@ anartificialhorizon : Post No 1645

I concur with your sentiments. As was the case with MH17, shot down and scattered across the eastern Ukraine, this new tragedy in the Sinai shows the zero understanding of the incumbent authorities and in-situ personnel (population) in dealing with events of this scale.
I applaud the quick actions taken by, inter alia, the British and Irish governments of suspending all flights to SES. A very short 24 hrs later the Russians eventually woke up and followed suit. Countries like Egypt, there are others too, will and are learning that in times of tragic events you either have the capability and capacity to deal with things or you don't. And if you don't then have the moral courage to let those who can get on with the job.

For lack of a better example - you need to crawl before you can walk and you need to walk before you can run.

rog747

7th Nov 2015, 15:51

Walnut

7th Nov 2015, 15:55

I am perplexed as to why the crew of NSW1969 at FL330 10miles apart did not see the Russian Jets explosion which was only 2000ft below, it would have been right in their eyeline, in fact it was probably the traffic stopping their descent and if they were not on radar they would have been eyeballing it.

rog747

7th Nov 2015, 15:58

walnut

it was 10km not 10 miles afaik

metrojet is at 400kts
nordwind is at 500kts would they have already passed at the explosion?

dsc810

7th Nov 2015, 16:01

Maybe its is just that the crew of the other aircraft in the vicinity feel no need to "share" their observations (if any) of the events with the general media or PPRUNE.

When that bizjet crashed at Blackbushe in the UK a few months ago the AAIB's initial statement of known facts a few weeks later mentioned a change in the circuit pattern by the jet to accommodate a slow flying microlight.
This was the first anyone had heard of the presence of a microlight and those flying it have never made any public statements - though I'm sure they have made one to the AAIB.

Chronus

7th Nov 2015, 16:07

i have to say this sorry accident has been discussed on Pprune in a far more calm and sensible manner by most 99.9% on here than previous bun fights which have occurred on other accident discussions and sharing -

i have read every page & thread from the start in this fascinating and developing story

hope we can all keep to this decorum and cordial

at the end of the day 224 holidaymakers perished with implications for the future of travel to Egypt in the balance

ps any comment re my post 1656?

RE # 1656

Sighting unlikely. More important ATC comms after SSR contact lost and possible primary radar trace of break up. At this stage we don`t have any information on ATC tapes and whether other traffic was requested to report sighting or to relay. Depends who was on whose frequency.

mitrosft

7th Nov 2015, 16:08

Re post 1565 by rog747

There is no time stamp in twitter pic. Assume Nordwind passed KG before event.

Even if they were in sight during the event, initial blast may not have produced flash big enough for NW to notice, as fuel probably ignited few seconds later.

oldoberon

7th Nov 2015, 16:09

i have to say this sorry accident has been discussed on Pprune in a far more calm and sensible manner by most 99.9% on here than previous bun fights which have occurred on other accident discussions and sharing -

i have read every page & thread from the start in this fascinating and developing story

hope we can all keep to this decorum and cordial

at the end of the day 224 holidaymakers perished with implications for the future of travel to Egypt in the balance

ps any comment re my post 1656?

I have not seen any statement related to what the NW aircrft did or did not see.

In the press today on the article about the thmson aircraft missing a missile by 1000ft, it said another thomson aircraft on approach to sharm saw it and reported it.

I would have thought at 10mls virtually straight ahead in clear skies they must have seen the aftermath especially once fire broke out. In fact they are probably the only eyewitnesses (unless the fake vid isn't fake).

Assuming as stated they had not already passed each other

theron

7th Nov 2015, 16:11

Kulverstukas:

Wow, this press event was not worthless. Not every part of plane was found. FDR stops at 4:13:20.

And FR24 data shows flight disruption starts at around 4:13:00. If these times are accurate, hopefully something useful will show up in those last few seconds.

rog747

7th Nov 2015, 16:12

mitrosft re my post 1656

my point was that if the isis videos were real and Nordwind had the KG insight then the extreme black smoke seen in those videos would/should have been visible to the NWS unless they had already passed

i haven't done the maths of when they should passed each other as i cannot find the times for NWS A321

thanks chaps for other replies

Pontius Navigator

7th Nov 2015, 16:28

. . . I have a good idea of how explosions are imaged by video cameras.

The disperancy in the black level of smoke versus the airframe is my main issue.

Yes if the video is real the smoke could have been processed separately to alter its black level for dramatic effect. . . .

However a common trick to help marry composite elements is to leave or make the frame wobbly.

Am I correct in assuming that you say there are three elements to the video:

An aircraft in flight
An explosion
A smoke trail

That the first two are genuine but independent and that all three have been fused in to one video?

I would not disagree with that.

My initial post was only to cast doubt on the assertion that the explosion was FAKE as opposed to the whole composition being fake.

Mesoman

7th Nov 2015, 16:29

I looked at specs for a couple of CVR's. One had a bandwidth of 3kHz and the other 5kHz. The microphone bandwidth would likely have been higher.

This means that a sample of the sound (think "relative" pressure) was recorded about every 100 microseconds. In that time, a sound wave travels about a couple of centimeters in air, and quite a bit more in metal. This means that the differential between microphones gives some information about the direction of arrival of an impulse, and its speed of propagation.

If the initial event was a low velocity explosion (such as a fuel tank) or an explosive decompression, there might be time for sound to get to the cockpit before the signal carrying cable was severed. If it was a high velocity explosion (C4, SEMTEX, PETN, ANFO), that sound could get there only if the explosion shock wave itself did not sever the cable, but rather just weakened the fuselage structure leading to an eventual breakup (milliseconds to seconds later).

Whether the fast rise time characteristic of a high velocity explosion shock wave could be distinguished is another question. A lot of material would be filtering out the high frequency components as the shock wave traveled from aft to the cockpit, although it might be conducted through the metal of the airframe, which would better preserve it.

Finally, the "sound" at the end of the CVR might just be the electrical transient from the cable being severed, and perhaps also from power being removed.

All of which brings up a question I've had during this very interesting thread: is there a reason we are not discussing a center fuel tank explosion? There have been a some of these in commercial jet aviation history, most notably TWA-800.

G0ULI

7th Nov 2015, 16:32

There have been several mentions of lack of oxygen being responsible for the thick black smoke which appears in the videos.

The relative mixture of atmospheric gases is the same at 30,000 feet as it is at sea level, only the pressure is lower.

Cabin pressure in a high flying aircraft is maintained by outside air being compressed and vented into the cabin. If there were less oxygen at altitude, then this technique wouldn't work.

In event of depressurisation occuring, supplementary oxygen masks are deployed for passengers because the human body can't extract sufficient oxygen from low pressure air, not because the air itself has any less oxygen.

Sufficiently fit and acclimatised individuals are capable of surviving at equivalent altitudes for several hours without supplementary oxygen as proved by unassisted ascents of Mount Everest.

Pontius Navigator

7th Nov 2015, 16:33

. . . if the isis videos were real . . . the extreme black smoke seen in those videos would/should have been visible to . . .
Satellite observation as both a scar in the sky and a matching shadow scar on the ground.

sarabande

7th Nov 2015, 16:34

"When that bizjet crashed at Blackbushe in the UK a few months ago the AAIB's initial statement of known facts a few weeks later mentioned a change in the circuit pattern by the jet to accommodate a slow flying microlight.
This was the first anyone had heard of the presence of a microlight and those flying it have never made any public statements - though I'm sure they have made one to the AAIB."
IIRC, It was well reported and discussed at an early stage as a possible indicator that the private jet pilot was cutting corners.
http://www.pprune.org/images/buttons/reply_small.gif (http://www.pprune.org/newreply.php?do=newreply&p=9173327&noquote=1)

gawbc

7th Nov 2015, 16:43

I was intrigued about the video, I have been away and started piling through this at about page 60 not realising a video had been released.

I have no idea whether it is true of fake but what struck me was that right from the off it looked like a high wing four engined aircraft (C-17, Il 76, A400) and if you freeze the video at 1 second, to me there are 4 lines which could look like engines.

Certainly did not look obviously airbussy to me but it's not the greatest video.

(By the way I was the UK Air Cadet individual champion at aircraft recognition...........in 1973-74 :E true, so either I am spot on, or lost my touch!)

rog747

7th Nov 2015, 16:43

seems the wreckage trail has been mentioned in the press conference at 13km

The tail section of the aircraft was found at coordinates N30.1527 E34.1858, 2230 meters/1.2nm south of the main wreckage and south of the last radar position

On Nov 7th 2015 Egypt's Air Accident Investigation Commission (EAAIC) reported in a press conference, that:
- the wreckage is distributed over a length of more than 13km consistent with in-flight breakup, several parts of the wreckage are missing.
- Initial observation of the wreckage does not yet allow to determine the cause of the inflight break up.
- The FDR was successfully downloaded, preliminary review of the data suggests the recording stopped 23 minutes 14 seconds after becoming airborne, last recorded altitude was 30,888 feet MSL, last recorded airspeed was 281 knots IAS, autopilot 1 was engaged, the aircraft was still climbing.
- The CVR was successfully downloaded and a first listening was done, the transcript is currently being compiled, a noise was heard in the last second of the recording. Spectral analysis is trying to determine the nature of this noise.
- Parties reporting facts outside of the investigation should provide their evidence to the accident investigation commission ( this appears to be a reference to British and US Intelligence heard chatter suggesting the aircraft was brought down by a bomb).

Mr Optimistic

7th Nov 2015, 16:45

Thick black smoke which p!umes and billows? Looks like the smoke rising vertically from a oil fuelled fire in still air turned through 90 degrees and overlaid. Just sayin'.

Uncle Fred

7th Nov 2015, 16:54

Tdracer and Mesoman. Very good contributions from the both of you (as well as others) on the characterists of sound propogation. This has really assisted in learning/understanding of what might have been on the CVR. This is where Pprune is quite the worthwhile read. Keep up the intelligent discussion.

Frankly this has been one of the most reasonable threads in a long time.

nnc0

7th Nov 2015, 16:56

After the ISIS video shows the explosion, the aircraft continues flying for an additional 15 seconds before the video ends with the fuselage relatively still in one piece.

According to the authorities, the CVR records a loud noise of some sort and then nothing. No aural warnings or alarms after that. The CVR is powered from the essential bus so shouldn't we expect alarms and bells after the explosion if that video is real.

Kulverstukas

7th Nov 2015, 17:06

last recorded airspeed was 281 knots IAS

So no drastical speed drop at recorders, means tail separation was before speed drop.

nnc0

7th Nov 2015, 17:10

All of which brings up a question I've had during this very interesting thread: is there a reason we are not discussing a center fuel tank explosion? There have been a some of these in commercial jet aviation history, most notably TWA-800.

If I read the maintenance spec correctly it seems it was a retrofit ACT installation. Can't tell when it was installed though. Recently? Last heavy visit?

Must admit the similarities with TWA circumstances are notable.

Aberdare21

7th Nov 2015, 17:11

Forgive me if its stupid but if the screw jack was deliberately tampered with would the possible result be the same as structural defect and the tail detaching from the rest of the aircraft ?If so wouldn't that obviate the need for explosives and account for, as far as I have heard, no residue being found.

auldlassie

7th Nov 2015, 17:15

Note that a lot of post here a referring to "the video" but most posts do not provide a link to the video they are talking about. Even if responding directly to a particular post, they do not reference that poster by name. This only causes confusion which escalates in further responses. :(

The web is now a source of multiple versions of these videos, both as copies/part copies of the earliest ones or newer ones.

From back posts at least 4 different videos have been mentioned. One at the beginning which I believe from some posts only showed wreckage. This caused some confusion then. At another point more recently in the thread videos were again being discussed and 2 different ones were weblinked. I cannot find them now. Both showed 2 different recordings (videoed by 2 different sources) of a plane, losing its tail then exploding and continuing to come down on fire but with wings attached. So, 2 videos, each with 2 different recordings. In each of these 2 videos, one recording was duplicated, but that still gave us 3 different recordings of the same incident.

It would be very helpful if those posting further comments on video content could include the link they are referring to. This should be simple enough, as presumably they will have recently watched it and have the weblink open.
I think a lot of readers would appreciated that. Thank you.

RYFQB

7th Nov 2015, 17:27

There is no time stamp in twitter pic. Assume Nordwind passed KG before event.
And FR24 data shows flight disruption starts at around 4:13:00.
The values shown in this pic can be found in the raw data from FR24, and the corresponding time stamp is 04:13:17.761, or about four seconds after the upset, which appears at 04:13:13.671.
http://images.scribblelive.com/2015/10/31/1c1ed9dd-a8a3-4a8d-ae32-5865cc530e8f.png
Given this was an official FR24 receiver, the time should be GPS synched. I don't know anything about the clocks in the FDR and CVR.

gawbc

7th Nov 2015, 17:29

Apologies, here is the video I looked at

https://www.youtube.com/watch?v=oQi34dJis4E

Pontius Navigator

7th Nov 2015, 17:40

gawbc that video is the same as on the Daily Express web link. The last section of the video does not seem to relate to the initial bit.

It also strikes me that something is missing from that aircraft at 33,000 feet. There are no contrails or even visages of one starting.

What was the contrail height that day?

TwoHeadedTroll

7th Nov 2015, 17:44

Can the videos be synched, at least to determine if they are exactly compatible with each other?

ionagh

7th Nov 2015, 17:50

@mickjoebill

"Having filmed 3 airframes being blown up as well as gas, petroleum, dust explosions, flashovers and numerous controlled demolitions for science docs I have a good idea of how explosions are imaged by video cameras."

My mispent youth in fire research agrees 100% with your conclusions. Having also worked in photo manipulation and other graphic artistry my first reaction to the video was to laugh.

I remember a documentary by an NTSB expert who said if you don't have recorded data then find all four corners and start from there. As far as I can see they haven't found all four corners yet.

Kulverstukas

7th Nov 2015, 17:53

"First" video quite possible from somebody reaching site before rescue team, I read complains that place was looted before investigators begin secure it.

It's also not improbable that some of soldiers who arrive at the place first make video with their phones and post it in social media.

Simplythebeast

7th Nov 2015, 18:08

Weve seen footage and photos of the nose cone, the rear fairing off the APU and the full wing.Isnt that all four corners?

FDMII

7th Nov 2015, 18:14

Weve seen footage and photos of the nose cone, the rear fairing off the APU and the full wing.Isnt that all four corners?
Not quite. In terms of physical evidence we don't have the right HS & box + motor/screwjack; we only have the left HS. I'm not sure we can account (photographically), for all the fuselage between the main wing box and the VS wreckage.

ionagh

7th Nov 2015, 18:15

@Simplythebeast

Maybe four corners geometrically but certainly not aerodynamically.

Redlands

7th Nov 2015, 18:34

Probably safe too say, that 'people in the know' will have all the relevant information re; the video clip and are fully aware if it is relevant or not.

PAXfips

7th Nov 2015, 18:48

TASS: Russian Politics & Diplomacy - Experts search for explosive traces on A321 plane fragments ? anti-terrorist committee (http://tass.ru/en/politics/834509) do some real search for evidence beyond "intelligence":ok:

Orestes

7th Nov 2015, 18:57

Regarding the authenticity of the supposed video - here's a link to a photo sequence of the 1960's mid-air collision of an XB70 Valkyrie and an F104 Starfighter. Please note that as the Starfighter breaks up, spills its fuel and burns at altitude, there is a significant LACK of dark black smoke.

https://www.youtube.com/watch?v=nEP7niGqiNg

Pontius Navigator

7th Nov 2015, 19:14

Orestes, what you have there is a clean fuel fire. What the infamous video shows is black combustion product rather than a fuel fire. Clearly there is a difference in flammable potential between the two types.

DIBO

7th Nov 2015, 19:15

I've read here several video professionals/analysts discarding the video as a fake, unfortunately without sharing any analytical material/proof.
With absolutely no knowledge on the subject and very basic tools, I made this crude composition image after a frame-by-frame analysis. These are the first 6 second of the 'event'. What strikes me, if it is supposed to be a fake:
- it's a twin-underwing engined ac (so no old DC9 footage, nor a four engined plane as was stated by some)
- why went they through so much trouble creating shockwave effects, prior to the fireball, that nobody notices anyway. Difficult to see on these stills, but the first downward and directly following upper left/right 'shockwaves' resemble a fighter approaching/going supersonic
- if it's a fake why went they through the sudden colour change from blue-ish to purple-ish (which has no added value while creating the fake)
- the fireball is build up very progressively but consistent and separates in the smoke trail in a very believable fashion.
- if this was created in some game/simulation software, this must have been a pretty realistic simulation tool (shockwave/fireball wise), on which they went through a lot of trouble adding 'poor-quality' effects, heavy shaking, etc.
- and they did it twice, the first part of the video is rather close in-line with the flightpath, the second part (not included here) is more offset to the left (by 20-ish degrees) and at a flatter angle (farther away).
- if it's a fake, I rather would expect it to come from well equipped youngster with a lot time to waste on it, rather than the 'real' bas...ds which are actually in a conflict/war zone.

As a totally unqualified person, I have a rather bad (= 'real') feeling with this footage being made using consumer/smartphone quality devices, maybe 'upgraded' by some pop-on optical zoom-lens for smartphones. And without much video/special effects editing, only too much digital zoom. But I hope I'm wrong and that it's just some despicable video(game) crafting.

http://www.anony.ws/i/2015/11/07/Metrojetcrash.png (http://www.anony.ws/image/JnaU)

DaveReidUK

7th Nov 2015, 19:19

ps any comment re my post 1656?

In a heavily moderated thread like this one, it's pointless referring to posts by number as they may well get renumbered due to previous posts being deleted.

Use the Permalink facility and we'll know which post is meant.

PersonFromPorlock

7th Nov 2015, 19:23

Thick black smoke which p!umes and billows? Looks like the smoke rising vertically from a oil fuelled fire in still air turned through 90 degrees and overlaid. Just sayin'. It happens (https://www.youtube.com/watch?v=v5NeRuCYyfw). For some reason, the video is black until 1:25.

Smott999

7th Nov 2015, 19:23

Dear video enthusiasts:
Given the beautiful plume of black smoke for so many seconds, please explain the pristine, soot-free nature of the tail empennage.

And PLEASE take it to another thread.

tubby linton

7th Nov 2015, 19:26

Comcentrating on alleged video is only serving to enhance the credibility of those who allegedly made it. Even if it were a true representation of what happened ,(which I doubt) it still doesn't expliain where or how a device was planted or how the aircraft disintegrated.
Is there any point discussing the finer points of this video manipulation?

RatherBeFlying

7th Nov 2015, 19:32

A high velocity explosion inside the aircraft may produce smaller fragments that upper winds can carry for considerable distances. The pieces closest to an explosion will be the smallest and most scattered and be of most interest to forensic investigators.

It will take a lot of manpower to search the entire area where fragments may have landed.

Until more evidence is made public, I do not yet see enough facts to decide between a bomb or structural failure.

ZOOKER

7th Nov 2015, 19:42

Also, desert surfaces change rapidly due to aeolian activity. Small objects can easily be covered in a very short time.

upperecam

7th Nov 2015, 19:42

I note no mention of APU compartment as a receptacle. It was parked overnight.

oleostrut

7th Nov 2015, 19:46

lomapaseo

7th Nov 2015, 19:57

It makes a difference in many ways where a bomb was located. If it was ahead of the engines there is likely to be debris impinged on the cowls and/or ingested.

Ruimte Aap

7th Nov 2015, 20:02

We know there has been a fire, not only on the ground but also in the air. We can see smoke marking on fuselage sections where the ground has no evidence of fire so that indicates inflight fire at some point (http://www.pprune.org/rumours-news/569907-breaking-news-airliner-missing-within-egyptian-fir-35.html#post9167703). Sections of fuselage like the one discussed before on the port side, just behind the wing, that have been ripped of the trusses like the section with the wing light and the hole with “flap”, probably made on landing by a tube of the seating frame and a sharp edged holes in the sooted grey area (http://www.pprune.org/rumours-news/569907-breaking-news-airliner-missing-within-egyptian-fir-36.html#post9167734). That particular section shows that there seems to have been a force pushing the panelling out: a window that has been pushed outwards from the fuselage and also fire: soot markings from the emergency escape slide. Below that, in the area of the hold (painted grey) there is also evidence of fire seemingly inside the hold.
There is another section of ripped off fuselage (http://www.pprune.org/rumours-news/569907-breaking-news-airliner-missing-within-egyptian-fir-35.html#post9167649), I think from the opposite (starboard) side, showing the same kind of soot and burn markings. The Aluminium skin has been burned through in places but again not where the trusses and ribs etc. were fitted. I understand that this is roughly the area where the central fwd/aft fuel tanks are. See also (http://www.pprune.org/rumours-news/569907-breaking-news-airliner-missing-within-egyptian-fir-70.html#post9171924) All these sections, including the empennage, have been found in the same two debris areas. It would be interesting to know where the sections are that have fallen down earlier in the disaster process. (satellite image?)
I have been looking at this a number of times now and it puzzles me still. I personally am not buying the “outside force” scenario, that to me is just scaremongering/propaganda until they declare to have found evidence of it.:rolleyes:

Prada

7th Nov 2015, 20:05

Wow, this press event was not worthless. Not every part of plane was found. FDR stops at 4:13:20.

Flightradar data shows thar flight became unstable at 4:12:58 and last data was at 4:13:22

How comes there is nothing on fdr? Someone is lieing?
How fdr time is synced?
flightradar time is added at the moment of receiving.

Old Boeing Driver

7th Nov 2015, 20:09

I agree.

Far more important to know who, what, where, why, when, and how the device was placed and detonated.

Smott999

7th Nov 2015, 20:31

PN I'm seriously asking about how, given the video showing extended moments of black smoke engulfing the rear of the aircraft, how could the tail empennage, still attached in the video, wind up apparently soot-free?

Ian W

7th Nov 2015, 20:32

Israel is absolutely silent on the whole matter. For those of us that have slightly deviated from military instructions (not Israeli, necessarily) when operating under their guidance, you know how accurate their equipment is. They saw and recorded the entire event.

With Israel's experience with the Sinai, they watch that airspace very closely.

Of course, the US knows as well from their various satellites monitoring in real time.

If it were a purely structural breakup, the major powers would have been clued in.

Judge the past by the actions in the present.

Well, I agree that the major powers may be clued in. Their actions in the present though are greatly modified by international relations, political mores, expediency, how close (in date and result) future elections are... Do not ever think you can ascertain reality by assessing the actions of politicians or their governments - that is a fools errand.

RTM Boy

7th Nov 2015, 20:34

So, as the CVR recorded a 'bang' and based on the photos we have seen, it seems almost certain that there was some sort of mid-air fire.

With all the theories around structural failure expounded, can anyone give a rationale for a mid-air fire?

Surely the only potential explosive fuel would be jet fuel. But kerosene only ignites easily in atomised form and where there is plenty of oxygen available. At FL310 oxygen levels are at about 6.5% (c/f 21% at sea level). Could sparks from structural failure really be sufficient to ignite kersone given the rush of air from massive sudden decompression and the air stream of say 400kts that would suck sparks away from the aircraft almost instantaneously? And that would assume that kerosene was escaping in large enough quantities following a structural failure.

I can't think of a single example of serious structural failure and/or decompression that resulted in a mid-air fire. Loss of control, yes. Fire, no.

Speedbird 911 (Japan 1966) no mid-air fire
Braniff 250 (USA 1966) no mid-air fire
Lake Central 250 (USA 1967) no mid-air fire
BEA 706 (Belgium 1971) no mid-air fire
AA 96 (USA 1972) no mid-air fire
Turkish 981 (France 1974) no mid-air fire
AA 191 (USA 1979) no mid-air fire (despite huge fuel stream from port wing at low altitude)
JAL 123 (Japan 1985) no mid-air fire
United 811 (over Pacific 1988) no mid-air fire
El Al 1862 (Netherlands 1992) no mid-air fire
China Air 611 (Taiwan 2002) no mid-air fire

Surely, the only possible 'accidental' cause could be a catastrophic engine fire combined with simultaneous damage to the fuselage and fuel tanks, which would surely have had to include wing tanks?

But even then would the aircraft not have continued under normal flight for at least half a minute?

Am I missing something?

Pontius Navigator

7th Nov 2015, 20:59

Smott, all I am saying is that the video must be properly analysed before being discounted. I agree, soot is an important feature but there are still too many holes to discard any piece.

There have been regular summaries of physical bits that are known to be missing but there are other things too. No one has answered my query about contrails.

All we need is one pilot who flew that day, or even since, to confirm that there were no contrails, as in the video, or not. If there were persistent trails at that height then that would nail it.

A0283

7th Nov 2015, 21:01

If you would list some observations as follows:

a. RUS and EGY experts officially stated earlier that no traces of explosives have been found on any of the examined victims (would be nice to have a link to an official statement, not an interview),

b. A loud NOISE at the end of the CVR recording, as officially stated today by the chairman of the investigation, he clearly does not use the word EXPLOSION,

c. No clear evidence (my impression– clearly not shared by quite a number of posters) of high velocity fragments or blast or flash on the outside of components and parts of the plane that are visible onpictures in the public domain, and certainly not many ‘possibles’ in this respect,

d. Amazingly ‘clean’ wreckage,

e. Break-up fracture lines include quite a few that are along what I call “production breaks”, where with an explosion you would expect multiple more ‘ragged’ edges, and with fatigue you would fractures further away from “production breaks”. This suggests structural failure ...

f. ...

What kind of scenario wouldb e able to cover this combination of ‘dots’.

An option might be a kind of very local, very high temperature event, weakening the structure or ‘flash through’,going from aft cargohold to the tail (via ducts?), leading to a growing overload situation, after some time causing a violent failure (triggers could be, pressure-differential exceeding a certain limit, or load caused by A/P1 induced step inclimb, or..), the violent nature of this causing the very loud noise, the chain of events proceeding so fast, that it leads to the loss of significant structural member(s) (for example pushing out the THS and APU and kicking out the rudder), a loss that instantly causes an irrecoverable loss of control, a combination which makes it impossible for the pilots to disengages A/P1 (high g’sand or surprise effect), aerodynamic loads then causing the subsequent fast break-up of the plane,

Some questions could then be:

i. What kind of event and/or product could lead to such an fast escalation within about 23 minutes of flight plus some additional time between pushback and takeoff, so say between 20-35 minutes, could that be Lithium-batteries or ...? And what would be the cause of cargo hold sensor (smoke/temperature) failures.

Hope someone can help me toget this scenario up to a more “probable” level.

Note: “Probable” not suggesting that this is THE only or even the most likely scenario.

+++

While i was writing this RTM Boy posted http://www.pprune.org/rumours-news/569907-breaking-news-airliner-missing-within-egyptian-fir-86.html#post9173575 covering the subject of in-flight fire. Not the same as my scenario, but recommended reading his parallel to mine.

Redlands

7th Nov 2015, 21:01

A fire in the hold would surely elicit response/record on cvr/fdr.

mary meagher

7th Nov 2015, 21:01

According to the New York Times, Vladimir Puchkof, Minister for Emergency Situations reported samples from the wreckage have been taken to Moscow.
Said he, "Russian specialists have collected swabs and scrapes from all fragments of the aircraft, luggage, and soil. The necessary samples have been taken from all items which might contain traces of explosive. All these samples have been delivered to Moscow and are being thoroughly examined now."

A0283

7th Nov 2015, 21:06

As far as i have read, there are two testing sequences. The first that of the passengers starting a few days ago. The second the one you mention now. It would not surprise me if we get a third one when the missing components are found.

ThadBeier

7th Nov 2015, 21:44

I'm a visual effects artist, as well as a pilot. For analyzing this video, I'll put my VFX hat on. I've made a huge number of films, you can look it up.

1) Given the orientation of the plane in the video, it has to be at least seven or eight miles away (altitude of 30,000 ft or so, and at a significant horizontal distance as well). If you look through seven miles of atmosphere, you cannot see anything black -- blacks become blue due to Rayleigh scattering.

https://en.wikipedia.org/wiki/Rayleigh_scattering

Note that the sky is actually black, but the scattered light from the sun makes the sky appear blue.

Now, ok, say that they processed the footage to bring down the bluish-blacks to look more black? I don't know why they would do that, as it makes it look less real, but if they did it would be very noisy and low-contrast.

2) Tracking the relative speed of the smoke plume to the plane isn't that hard. The span of the plane in one of the frames is 74 pixels. As the span of a A321 is 117 ft, that means each pixel is about 1.6 ft. During a half-second the smoke drifts back 37 pixels, or 116 ft/sec (80mph) if the plane was directly above the camera, or 232 ft/sec (160 mph) if the plane was only 30 degrees above the horizon. We know that the plane was going far faster than that.

3) It appears that the footage was filmed on a smartphone that was pointing at another LCD screen, perhaps even two generations of re-filming. Several instances show quick pans where the plane doubles-up, as if the camera was out-of-sync with the screen it was filming. The very strong contrast between the middle of the screen (pretty bright) and the edges (quite dark) leads me to believe that the smartphone camera was quite close to a cheap LCD screen, which has big variations in brightness with viewing angle.

The blackness of the smoke at a distance of many miles, and the slow speed of the smoke relative to the airplane lead me to believe that this is shoddy visual effects work. It could easily have been done by anybody during the 24 hours between the crash and the release of the video.

Bertie Bonkers

7th Nov 2015, 21:49

Well, I agree that the major powers may be clued in.

Though speaking as someone who was once a hard-core conspiracy theorist, I would suggest that beneath the veneer of competence, the governments of major powers know little more than the rest of us and are, in this case, simply erring on the side of caution. In fact it would not surprise me at all if there were currently people in Whitehall and GCHQ following this and other aviation forums in the hope of picking up any useful information and/or professional insight which might be of use in establishing a probable cause for the incident.

Etud_lAvia

7th Nov 2015, 21:51

@RTM Boy (on the subject of mid-air fire)

I understand that it's very difficult to ignite or sustain fuel combustion outboard the aircraft at FL 300+

But of course, the aircraft took some time to reach the ground, and soon passed into much denser air.

For example, TWA 800 fell with a "fire trail", the appearance of which was interpreted by some witnesses as an ascending missile. That flight's break-up initiated around 14,000 ft. I don't know whether the streaming fuel fire ignition source was determined -- it might have been by the explosion, but conceivably the heat of the explosion passed in a moment and the streaming fuel was subsequently ignited by another source.

If we imagine the Metrojet A321 breaking apart at altitude, and fuel streaming from a ruptured center tank, static electricity is a possible source of ignition (as the fuselage falls into sufficiently dense air).

In addition, with extreme damage to the aft of the plane, and the tail perhaps already separated, severed electrical cables might well have been persistently arcing in open air, where the arcing could come into contact with a fuel/air aerosol streaming from the center tank.

Probably, at least one engine was still turning, with its generator powering the plane's electrical systems -- arcing might have continued all the way to ground impact.

Sick

7th Nov 2015, 22:01

Fuel uplifted in Sharm would be very warm, and still would be warm at the TOC.

silvertate

7th Nov 2015, 22:06

With Israel's experience with the Sinai, they watch that airspace very closely.

Of course. But Obama is not exactly flavour of the month with Netanyahu at the moment, so Israel is not going to assist until someone starts appreciating the full political problems and implications in the region.

As I said before, this is 30% aircraft investigation and 70% political intrigue.

Silver

oleostrut

7th Nov 2015, 22:08

"e. Break-up fracture lines include quite a few that are along what I call “production breaks”, where with an explosion you would expect multiple more ‘ragged’ edges, and with fatigue you would fractures further away from “production breaks”. This suggests structural failure ..."

The damage we are seeing is entirely consistent with a small high explosive device. There is shattering and jagged damage in some areas, and very clean tensile skin failures distant from the blast.

Ample proof easily viewed by searching for such gov't tests on airframes. The breaks on this Airbus look the same.

A huge explosive device could shatter the entire airframe, but that is not what is suspected.

Prada

7th Nov 2015, 22:25

I start it backwards.

Forward part fell to ground tail first upside down. That is due to aerodynamics and gravity center.
Before ground impact there was a fire underside between wings. Left underside up to the nose is sooted.
Left Engines probably ingested hot gasses from fire during falling phase. Main fan is sooted and scorched. Engine shows over heating damage.

These facts we know for sure.

Plane breakup last phases were abrupt with tail separation. There is very large piece of fuselage of right side. Almost from wings to tail. That one was last to break off. It could be that tail was last piece to break off from rear fuselage. At near cruising speed. That would explain strange hs and vs damage. Somewhat.
there was fire. First insid rear part that scorched seats and bodies.
could be it started from act tank installed on the plane. It was probably almost empty. But that is not sure.
fire started close to initial event.

Here i stop speculation.

MountainBear

7th Nov 2015, 22:46

A fire in the hold would surely elicit response/record on cvr/fdr.

No.

I understand that it's very difficult to ignite or sustain fuel combustion outboard the aircraft at FL 300+

Irrelevant.

The fundamental assumption these posts make is that the instrumentation was working properly and being monitored properly. We don't know that. All we know is the that the flight parameters were normal.

It is possible that fire happened in the hold that went undetected or unnoted and by the time it right FL 300 damage was done.

I'm not saying that this is what happened; I still think a structural failure is more likely. But none of the evidence produced so far categorically eliminates the possibility of a fire being the proximate cause of the crash, the intransigence of the mods of this board notwithstanding.

StuntPilot

7th Nov 2015, 22:55

CONSO

7th Nov 2015, 23:11

#1548 (http://www.pprune.org/9172771-post1548.html) (permalink (http://www.pprune.org/rumours-news/569907-breaking-news-airliner-missing-within-egyptian-fir-78.html#post9172771)) and #1493 (http://www.pprune.org/9172441-post1493.html) (permalink (http://www.pprune.org/rumours-news/569907-breaking-news-airliner-missing-within-egyptian-fir-75.html#post9172441)) is IMO the closest realistic explanation of the sequence of events involved.

IMO it does not exclude explosive initiation- but it does cover the most probable sequence.

I note as many have- the loud noise on the CVR may resolve the structural failure/HS flapping or explosive initiation

Even so one wonders how or why the jackscrew- HS wing box has yet to be found since both cvr and fdr are located very close.

Please lets drop the video issue and the center wing tank issues as an initiating event. Way too many things simply do not fit either.:ugh:

Richard W

7th Nov 2015, 23:19

RTM Boy wrote, "I can't think of a single example of serious structural failure and/or decompression that resulted in a mid-air fire. Loss of control, yes. Fire, no", and gave an impressive list of 11 cases.

However, in five of the cases, the fuselage substantially remained connected:

AA 96 (USA 1972) no mid-air fire - landed!
Turkish 981 (France 1974) no mid-air fire
AA 191 (USA 1979) no mid-air fire (despite huge fuel stream from port wing at low altitude) (engine loss and impact damage)
United 811 (over Pacific 1988) no mid-air fire - landed!
El Al 1862 (Netherlands 1992) no mid-air fire (engine loss and impact damage)

The NTSB report records a mid air fire for:
Braniff 250 (USA 1966) 'tumbled down in flames' (to quote Wikipedia)

In the case of Braniff 250, one of the wings was torn off, and the mid-air fire is attributed to the consequent tank rupture.

Wikipedia agrees with the absence of mid-air fire in five cases:

Speedbird 911 (Japan 1966) no mid-air fire
Lake Central 527 [emended from 250] (USA 1967) no mid-air fire - severed at cockpit
BEA 706 (Belgium 1971) no mid-air fire
JAL 123 (Japan 1985) no mid-air fire - notorious for being semicontrollable
China Air 611 (Taiwan 2002) no mid-air fire

A0283

7th Nov 2015, 23:29

after the tail breaks off , HS failure and APU cone breakaway become much less likely.

A HS failure on the other hand can result in APU cone break away but after the HS is gone the tail breakaway is much less likely.

thinking about your two scenario's ...

First one. After the tail breaks-off (cause unknown), while considering the beefy 6-point tailmount, will probably leave intact the 'basically strong' cylinder of the tailcone. So immediate THS break-up appears to have lower probablility. The plane only starts rotating a while later. Losing the THS comes only after an increase of the aerodynamic loads.

Second one. If the THS is wrung out of position (cause still unknown), and one side breaks-off as a consequence of that. It could well take away immediately the 'double-paperclip' connection rod that spans the THS 'manufacturing insertion opening' on that side. Which immediately and severely degredates the strength and stiffness of that cylindrical area. Which then would at almost the same time, put the tail and other side of the THS out of position. With severe consequences. Which could well lead to a parallel departure of both tail and THS box and other half of the THS. This scenario appears to run faster than your first one.
It is not even necessary for this to push out the APU unit ... there is a possibility that the APU is still inside the cone.

So at first sight i think the tail could still come off. And consider your second option more likely at this stage and with the 'evidence' we have at this stage in time.

Confirmation or rejection of these scenario's of course requires checking and matching of the sequence with the pattern of the wreckage on the ground.

The most probable scenario could then be used to point back at the originating events.

+++

My impression was that we see only one half of the double paperclip in the structure. But i have to go back to the pictures to look at that.

dartmoorman

7th Nov 2015, 23:36

The threads on PPR are well moderated in my opinion - it is gaining popularity because it is well moderated and is now often quoted in the media . The reason to that is because the majority who contribute are involved somehow in the aviation industry and illustrate that with the technical knowledge expressed in the threads ..... This particular crash has some alarming issues - the amount of wreckage pictures being widely spread on the internet and the political ramifications already arising and still no definitive statement on the catalyst of the whole sad event .

wilyflier

8th Nov 2015, 00:00

Prada:

The interesting part is that after the tail breaks off, HS failure and APU cone breakaway become much less likely. A HS failure on the other hand can result in APU cone break away but after the HS is gone the tail breakaway is much less likely. Even a scenario where a 'pressure event' causes both the APU cone ejection and a HS damage, one expects that this causes either the tail to break after which HS failure is less likely or one expects the HS to break off fully, after which the tail is much less likely to break off.

A possible scenario is that there were multiple explosions because of the fuel and that the first one blew off the APU cone. Problem is that the damage pattern offers only weak support for it. I think this is the puzzle at the moment.

How about this....
HS Screwjack,, or support structure distorts/ disconnects for some reason
(One possible reason could be jackscrew thread or JS Nut thread worn and stripped)
HS now located only by rear pivot (behind icentre of pressure)
Airflow slams Hs to 90 degrees thus snapping off end stop, of and port HS
Instant disconnect of both flight recorders
Starboard HS and jack gear go too
Resulting shocks lead to general breakup/distribution of all tail parts
What is relative ground position distances of infant, both HS ,and tailcone parts??

oleostrut

8th Nov 2015, 00:06

WHBM

8th Nov 2015, 00:09

I can't think of a single example of serious structural failure and/or decompression that resulted in a mid-air fire. Loss of control, yes. Fire, no.

I described earlier the Tu144 accident at the Paris Airshow, widely video'd, where the major midair fire began within a second or two of the midair structural breakup.

https://www.youtube.com/watch?v=gWIWAI6GmQQ

wilyflier

8th Nov 2015, 00:21

"HS Screwjack,, or support structure distorts/ disconnects for some reason"

Would have sheared the wing off from overload, not broken the tail. The HS has a limited range of motion, and the upper and lower support structure is still there.

Sorry Oleo

I suggest Hs no longer constrained Flipping straight to 90 degrees ,little pitch moment to airframe, only colossal drag.#
Support still there? where is the screwjack?

oldoberon

8th Nov 2015, 00:22

i have extracted these figs from your link in your post

04:13:03 KGL9268 30.157 34.174 30650 296 332 -5696 32000
04:13:08 KGL9268 30.161 34.173 30825 246 351 4544 32000
04:13:11 KGL9268 30.177 34.162 29925 306 325 -6080 32000
04:13:11 KGL9268 30.177 34.162 29925 306 325 -6080 32000
04:13:12 KGL9268 30.179 34.161 29925 184 350 -4352

at 04.13.08 it suddenly changes heading by 19 deg clockwise, 3 sec later it has swung 26 deg back anti clock. and 1 sec later it has swung 25 deg clockwise

If those yaw figures and rates are correct would the VS withstand that?

I ask the question again would those rapid degree of heading changes cause the VS to fail or and what do the they indicate ie what could be the cause.

oleostrut

8th Nov 2015, 00:29

"Support still there? where is the screwjack?"

The fuselage rear assembly is the support, it is present at the crash. Turning 90 degrees is impossible as it was still attached a 2 of the 3 HS mount pins if you screw assy is disconnected.
With the pivot points still attached, the fuselage forms the range of movement limiter
Had it gone 90 degrees, there would be nothing left at all aft of the RPB.

Go look at the construction photos of the HS being mounted to the fuselage rear. Your scenario is not supported by the physical evidence at the crash site.

fando

8th Nov 2015, 01:06

http://i.imgur.com/V9RR9L1.png

The fr24 data with precision 0 is complete nonsense - if you dont want to expect a cycle in the path. some onboard system had no idea what is going on and guessing...

also... with precision 2 around 04:13:23/24 the plane jumps backwards (not shown in this image)

Mesoman

8th Nov 2015, 01:07

It looks like major structural damage (inferred from large TAS drop) occurred within less than 2 seconds from onset.

If you combine this information with the assertion that the CVR showed nothing unusual except a loud bang at the end...

Either that bang lasted a couple of seconds or the CVR was cut off before the significant changes in VV and GS. I suspect the latter - that the initial event was sudden and took out the CFR, and the odd excursions in the flight data resulted from damage due to the initial event, rather than odd excursions being the cause of aircraft failure.

CONSO

8th Nov 2015, 01:33

First 3 links to show installed location of FDR and CVR, CVR and then FDR

http://www.pprune.org/rumours-news/569907-breaking-news-airliner-missing-within-egyptian-fir-50.html#post9169622

http://www.pprune.org/rumours-news/569907-breaking-news-airliner-missing-within-egyptian-fir-14.html#post9165152 for CVR

http://www.pprune.org/rumours-news/569907-breaking-news-airliner-missing-within-egyptian-fir-14.html#post9165152 For FDR

NOTE - IMO to recover them- they were probably cut from wreckage and in areas we have not seen in photos although FDR has **only** dirt on bottom ?

attachment was to tail cone skin. Skin surrounded and was attached to major structure elements above and below jackscrew.

So where is jackscrew and HS internal Box ?

Not found ?- or not pictured ? - or removed for examination before pics taken ?

And therein lies the story ..:ugh:

andrasz

8th Nov 2015, 02:10

My last post until meaningful new information comes up:

There are a number of theories circulating from knowledgeable posters which miss some demonstrated facts. I know the thread is becoming very long, but to make any meaningful analysis PLEASE read what has been written before, and consider ALL factual evidence, not just those that fit a particular theory. Most of the clues lie in pieces of the tail, the wreckage distribution clearly shows that the front part continued on for some distance after the initial failure and the loss of the tail and most of the rear fuselage.

The tail section failed in a way consistent with a structural failure in the lower rear fuselage, that caused the entire tail to pivot downwards in a matter of milliseconds due to the HS exerting the force it was designed to do. This is consistent with the FDR/CVR data stopping abruptly at the time of initial failure. To promote any HS failure as the initial cause you must demonstrate conclusively that the failure marks and patterns on the tail section wreckage may be interpreted otherwise.

The left HS failed by being bent UPWARDS at a 90 degree angle against the still intact rear fuselage skin, clearly evidenced by the fracture marks on the composite upper skin. If this is presumed to be a part of the initial failure, you must explain how this happened other than by extreme aerodynamic loads when the severed tail tumbled placing the HS flat into the slipstream. In particular, if it is suggested that the HS failed after a runaway trim placed the aircraft in an unusual attitude, what forces could have caused the tail to break off after the left HS parted while the wings remained intact, leaving no trace of the upset on the FDR. (Note: there is NO WAY any unintended deflection of any control surface to the full stop position can break the tail cleanly off the fuselage, the control surfaces themselves would fail first as demonstrated by the tail of AA587)

The tail and the tailcone with the APU landed relatively close to each other, the HS was much farther away (presumably back along the track, but we do not know this). This implies that the tail/APU structure remained joined for a time after the left HS departed (something corrobated by the relatively intact upper part of the frame joining the two pieces). We have not seen any photos of the right and central HS and it is quite possible it has not yet been found, but the fact that it is nowhere nearby also confirms that the HS separated earlier than the tailcone. This disproves any blasting off by a RPB rupture theory.

There definitely was an in-flight fire in the central section as the scorching and soot on the engines (especially the fan, which landed away from all other wreckage and has no ignitable components) and some fuselage components with soot on the outside but no traces of fire on the inside cannot be explained otherwise. With the engines still running until g-forces caused them to break off in an upward twist as the wings & front fuselage decelerated, they are the likeliest ignition source if the integrity of any of the tanks was lost. The fact that the plane had an ACT in addition to the integral central tank should be considered, but also the severed APU fuel line could have provided the spilled fuel if pressurized. In hot & heavy takeoff situations it is normal practice to run the APU for bleed air to avoid the thrust penalty on the engines. However all this has zero bearing on the accident sequence, the clues are in the tail which parted before any in-flight fire erupted.

EVERYTHING else coming from the media quoting unidentified sources needs to be taken with a pinch of salt, especially those that contradict observable evidence (eg. 'burnt' bodies in the back, heat flashes, etc.)

MODS, could we banish all this nonsense talk about the video to a separate thread on jet-blast ? A) the aircraft was NOT downed by a missile B) those with knowledge of video making / editing have conclusively demonstrated it is fabricated. It has ZERO credibility, it was released hours after the news were already splashed over every conceivable news site, the persistent discussion adds a totally unnecessary clutter on this thread swamping meaningful posts.

CONSO

8th Nov 2015, 02:44

#1737 (http://www.pprune.org/9173786-post1737.html) (permalink (http://www.pprune.org/rumours-news/569907-breaking-news-airliner-missing-within-egyptian-fir-87.html#post9173786))

you must explain how this happened other than by extreme aerodynamic loads when the severed tail tumbled placing the HS flat into the slipstream
Great Post- agree with say 90 percent and especially the bit about video.

RE the quote above - I do take a bit of exception as to timing. Here is why. IF the tail section both both right and left HS plus VS were no longer connected to airplane- I believe there is NOT enough mass-momentum of the remaining tail structure to resist the very high bending loads involved to shear off the HS. - Of course it might be possible that since both HS wound up at 90 degrees to airstream, one HS ( left? ) broke first. And then the combination of VS and other HS would tilt into airstream at a low drag attitude and virtually fly off in a ' sideways' direction. Which **may** explain why jackscrew and HS BOX and RH HS have either yet to be found or have not been shown .

Which of course gets back to what was the initiating event ?
:confused:

oldoberon

8th Nov 2015, 02:46

https://twitter.com/Terror_Monitor/status/663196857498103809

ISIS reclaim downing of flight.

sopwithnz

8th Nov 2015, 03:06

Posted this a couple of days back ... this is Russian TV helicopter footage that seems to track from 'wings' crash site back along the whole track to parts seriously under discussion including one single set of three seats in the middle of nowhere on their own... may or may not be helpful to the real experts here, but it's unlike other footage or map of wreckage I've seen ...

https://www.youtube.com/watch?v=hTgEgb0DWpQ

9 lives

8th Nov 2015, 03:34

Could the FDR include a channel (or better two) for cabin pressure, with very high resolution? If two, one at each end. If there were to be an explosion aboard, there would be a sudden cabin pressure rise, then presumably, reduction in pressure. If two sensors, the timing and differential would give you an idea of the fore/aft cabin location.

It won't help here, but could help in a future crash to rule in or out, a cabin explosion...

To carry the idea to the next step, what if a cabin pressure change exceeding a certain "normal" rate, triggered a 7700 squawk - no pilot action required. ATC knows that a dramatic cabin pressure event has occurred - even if a battery powered self contained transponder is falling free, and sending mode C on the way down.

andrasz

8th Nov 2015, 03:50

@ CONSO

Your logic certainly requires some deeper thought. I would start with the left HS which was cleanly snapped off by an upward bending force at the weak point in the structure where the airfoil is mated to the much narrower HS centre section. Only aerodynamic drag could have done it this way. Pure speculation, but this weak point coud actually be a design feature to protect the hinge/jackscrew assembly so in case one HS fails in overload (eg. if hit by a departing engine), the plane can still remain controllable with the other HS.

I cannot envision a scenario where this could happen before the tail broke off, because in that case the entire plane would have needed to be in an attitude which would have also caused the wings to fail and especially the engines to depart. Since the wing-engines-forward fuselage stayed intact for some time and continued along the flight path in a descending trajectory (engines were found near the main wreckage), the tail must have parted complete.

As unlikely as it is, this suggests the HS must have parted after the initial failure and severance of the tail. One possible solution bridging this and your thoughts is that the left HS could have snapped off as the tail was pivoting down, a fraction of a second before the upper rear fuselage failed in tension, which may have provided the necessary counter force. Calculating the various forces at play here are beyond my abilities, but I'm sure there are people busy in Toulouse doing exactly this.

CONSO

8th Nov 2015, 04:37

re #1742 (http://www.pprune.org/9173822-post1742.html) (permalink (http://www.pprune.org/rumours-news/569907-breaking-news-airliner-missing-within-egyptian-fir-88.html#post9173822))

IMO applying a bit of Ocams razor - a ** possible** probable ** simple version goers like this all in a few fractions of a second or a few seconds

a) Jackscrew/fitting/pin/ breaks ( why unknown )
b) Both HS flip nearly 90 degrees to airflow such that tension on top of airplane and compression on bottom - Plane pitches up.
c) Left? HS breaks off - plane starts to roll/yaw
d) combination stress at frame forward of PB on top rips top in tension, and buckles bottom in compression. This due to tension load and internal pressure load.
e) Right HS and VS combined pull ** foward ** of PB section off-
f) align themselves with relative wind- sort of a v wing along with HS box and most-all of jackscrew - and " fly" away

OK- IF My version is partially correct- expect to find RH HS - HS Box and Jack screw and pivots and maybe part of VS pretty much together.

Enough speculation - agree that more info needed- and especially the jackscrew system and RH HS.

Have a good evening :8

andrasz

8th Nov 2015, 05:26

@ CONSO

I do not see how b) would be possible. The movement of the HS is physically limited by the slots on both sides of the fuselage, which do not permit travel beyond permissible range, even in case of a jackscrew failure.

For the HS to be able to pivot 90 degrees around the rear hinges, the lower half of the support structure and the bottom of the fuselage would need to go first (which it apparently did at some point), but that would turn the HS downwards. On the video screencap it is clear that the left HS failed UPWARDS, meaning pressure came from the lower surface. That would require a 90 degree turn upwards, but this would be prevented by the VS which is clearly still in place.

Also I do not believe the control surfaces have sufficient structural strength to exert such pressure that would break the tail off. The fuselage when intact is very strong and resilient to any bending force. A downward pressure on the tail would simply pivot the aircraft around the centre of lift. If the pressure is sudden and strong enough, the HS would fail first and downwards, before the fuselage would (eg. BOAC 707 in mountain wave over Fuji in '66)

I really do not see any scenarios corrobated by evidence from wreckage where the HS failure could have been the initiator, even though that was my prime suspect too until the HS photos surfaced.

PS: It's a good morning here :)

bud leon

8th Nov 2015, 05:39

There are some interesting discussions on the veracity of the video. I'm surprised that no one from government agencies has stated that the video is false. My recollection is that this is usually done.

DIBO provides a good analysis of why the video might be true. And the analysis suggest there may be an initial explosion and then an ignition of fuel. That sequence fits the possibility of an on board explosion and then an explosive ignition of aviation turbine fuel. That sequence fits some of the scenarios that have been put forward on this forum.

ThadBeier has put forward some very solid points on why it might be fake. There are two elements of ThadBeier's ideas I'd like to challenge though. The first is Rayleigh scattering. Rayleigh scattering generally applies to gases not solids. A black smoke plume is a plume of unburnt carbon particulates, not gas. If we can see aircraft and white contrails at those altitudes in colours other than blue, I really don't see why we can't see black carbon at those altitudes, particularly because I don't think Rayleigh scattering applies so much in this instance. The second is in relation to the speed of the plume. The plume does look too slow (just simply comparing it to contrails), however, the aircraft may have rapidly decelerated after the explosion, and would have been losing altitude quickly. So the vector is complex in relation to the camera position. The aircraft may have very quickly moved from fast horizontal flight to a vector which has a slow horizontal component and a vertical component accelerating from +ve (still climbing) to -ve.

It is very normal to see thick black smoke when aircraft fuel catches fire in air. There are any number of reason for the whole of the end of the flight not being taken including such simple mistakes as running out of memory.

I'm not saying it's not a fake, but I don't believe the arguments for it being a fake so far are strong enough.

Prada

8th Nov 2015, 05:52

I wont repeat my earlier description of failjre sequence. Which i did backwards on facts we know. I just continue.

It is not exactly known when and why engines became separated. But at least left engine has ingested hot gases from fire. It means forward part was already falling backwards. Probably. At slow airspeed. Unusual attitude.

Rear seats were shedded one by one. We havent seen any large piece of floor or left side fuselage. It would suggest that breakup started on left side at floor level. Near act tank fuselage left side was shedded piece by piece. Until fuselage became weak enough to break close to wings. Thats when tail became separated by aerodynamic forces at high speed. Connection to fdr was lost in initial event or burst. Thats when fr24 shows fast ground speed reduction. Ripping of hs, vs and tailcone is a result of rear fuselage separation that enabled abrupt attitud changes. Also explai s close proximity of tail and apu.

Antelope7724

8th Nov 2015, 06:05

On YouTube is a 21 minute video showing a Russian search team
sweeping a desolate Sinai area, near what appears to be a large piece of the fuselage probably from behind the wings.

Подробности с места крушения рейса Airbus 321 Когалымавиа в Египте
Details from the place of the crash of Flight 321 Airbus Kogalymavia in Egypt
https://youtu.be/Oa9Q8nCqB0w

In the video at the 8:58 to 9:03 minute mark are some grey flat objects that look like they might airfoil pieces?

Here is screen capture from that YouTube video:

http://i1016.photobucket.com/albums/af281/Antilope/Parts3.jpg

Mark in CA

8th Nov 2015, 06:09

I haven't seen this mentioned yet, but accordng to this article in the NY Times, "the Russian authorities have, unusually, asked the F.B.I. for assistance in the investigation, according to senior American officials."

"Russia has asked the F.B.I. to help analyze forensic evidence from the crash to pinpoint its cause, American officials said. The F.B.I. and its Russian counterpart, the Federal Security Service, often collaborate against common enemies like Al Qaeda and the Islamic State, but the request for help on the plane crash was seen as unusual."

http://www.nytimes.com/2015/11/08/world/middleeast/gaps-in-egyptian-airport-security-face-scrutiny-after-crash.html?ref=world&_r=0

OK, here's the full article:

http://www.nytimes.com/2015/11/08/world/middleeast/russian-plane-crash-egypt.html?ref=world

Machinbird

8th Nov 2015, 06:40

It is pretty clear to me at this point that whatever caused the failure along the frame in the crown of the aircraft ahead of the rear doors was the primary cause of this accident. The direction of the line of failure is indicative that only the lower part of the structure was performing its function. The area of the initial line of failure is in a production joint. See attached picture of a new A321 tail assembly. The different primer colors highlight the different sections. (Source NYTimes.com article on new Airbus Mobile Alabama assembly plant)
http://static01.nyt.com/images/2015/09/20/business/20-AIRBUS-JP3/20-AIRBUS-JP3-articleLarge.jpg

The direction of tear is symmetric on both sides of the aircraft. See this picture from hamster3null. When you consider that aircraft are typically designed with a 50% safety factor above maximum load, it is surprising that the tear propagated as far as it did vertically before it turned forward.
http://i68.tinypic.com/dng9wz.jpg

If it was a fatigue failure, then there should be adequate evidence from the failed skin at the top of the rear fuselage section to make that determination.
(You do not have to have the opposite side of the failure to prove evidence of fatigue, the two sides will mirror each other.)
If it was entirely an instantaneous type failure from overstress, that also will be evident, in which case we will have a good case for an internally planted explosive device.

I suspect that electrical signals and hydraulics to the tail are routed along the crown of the aircraft. Can anyone verify this?:confused:

auntyice

8th Nov 2015, 07:22

With the downward moment of the HS the upper surface is under tension and therefore would possibly be the first part to rupture with an over pressure.
If there was a bomb in the rear of the aircraft then the blast and secondary blast would be reinforced due to the divergent duct effect.
It would appear then that your conclusions seem pretty accurate as we continue to speculate on the final outcome.

DespairingTraveller

8th Nov 2015, 07:27

Posted by (http://www.pprune.org/rumours-news/569907-breaking-news-airliner-missing-within-egyptian-fir-88.html#post9173860) Budleon:
ThadBeier has put forward some very solid points on why it might be fake. There are two elements of ThadBeier's ideas (http://www.pprune.org/rumours-news/569907-breaking-news-airliner-missing-within-egyptian-fir-86.html#post9173641) I'd like to challenge though. [snip]

Rayleigh Scattering doesn't occur in the object being viewed (in this case the smoke), it occurs in the intervening gaseous atmosphere. It is particularly noticeable against dark or black objects because, by definition, they are not emitting or reflecting any light themselves, and so only the blue light scattered into the observer's line of sight is visible. For an aircraft at an altitude of 6 miles, 30 degrees above the horizon, the slant range to the observer is approximately 12 miles. Try looking at a mountain or similar 12 miles away and you'll readily see the blue tint over it.

Deceleration. At TOC, the aircraft will have had an airspeed of around 400 knots, or around 700 feet per second. To decelerate to an average speed of 232 feet per second in half a second would require a deceleration of many tens of g's. In fact, under a linear deceleration, it would have had to have come to rest well before the half second was up in order to achieve that average speed, suffering a deceleration of some 66g in the process. All while continuing on in an essentially unchanged attitude, as portrayed in the video. Unlikely.

Finally, I suggest following ThadBeier's advice and googling his filmography. I am not normally given to accepting "arguments from authority" at face value, but I think that you'll find that he is more than amply qualified to opine on the veracity of visual effects. Probably as well qualified as anyone on the planet.

sardak

8th Nov 2015, 07:37

I've reversed the sequence I was going to show these so that the "new" information is first. This is the aft end of N106US, the plane on US Air Flight 1549, Sullenberger's "Miracle on the Hudson," during the NTSB investigation. Point C is a point of reference through all photos. These are my annotations of a photo found here: https://www.flickr.com/photos/patricethomas/albums/72157623272797240

http://i.imgur.com/MGoVT85.png

From the NTSB report "The tail cone was separated from the original attachment points except for the right hand side lower location and no longer retained its conical shape. The auxiliary power unit (APU) was still attached to the remaining structure of the tail cone. "The lower third of the aft pressure bulkhead was sheared away." This is a photo taken from part of the NTSB report Document 43 ATC 3B - JFK and EWR Radar Files Filing Date March 19, 2009 0 page(s) of Data Photos (http://dms.ntsb.gov/pubdms/search/document.cfm?docID=313054&docketID=47230&mkey=73240)
http://i.imgur.com/JZvGoCC.png

All of the struts and cross bracing shown in this picture are flight structural members and not just for support during assembly. Some of these are missing from the second photo of Flight 1549 and all of the lower ones have yet to be seen in the Metrojet crash photos.
http://i.imgur.com/3a71rKa.png

This is the same aft frame #77 as above on the crash we're discussing. There has been some discussion that the spindly structure left of point A could be part of the THS control assembly. It might be part of the mechanical cable system for the rudder and horizontal trim, as something like this can be seen in the first picture near the THS controller.
The fittings from the next section aft, the tail cone with APU, are still attached to points A and B here and in the photo from Flight 1549.
http://i.imgur.com/9UuJnB0.png

Frame #77 is at the curved aft end of this section so the light area next to point B in the previous photo is this skin. The flight recorder notice is a reference point back to the other photos.
http://i.imgur.com/qcmYFK8.png

JRM2010

8th Nov 2015, 08:16

Earlier in the thread somebody asked if there were any images of the outside of the door which had the "marks" on the upper interior panel.

In the Russian TV video linked a few posts ago, the door is shown at 38 seconds - direct linke here (https://www.youtube.com/watch?v=hTgEgb0DWpQ&t=37s).

Vc10Tail

8th Nov 2015, 08:38

I too have been boggled from the onset of this active searching thread why, especially considering how close the event took place near the reactive "Bibi's" hot spot border that Israel is speechless..... It just doesn't add up! That event took place soon after that track change away from Israel as has been shown from the trackers and all other photos depicted. The ATC tapes might help point under which Controller that doomed Airliner was being supervised. From initial reports it certainly fid not seem it was under Cairo ACC controllers...mention was made of Cyprus and Turkey!!!

Centre fuel tank mischief ( including fuel leaks) should rule out. This plane had flown over 50,000 hours...i wonder how many cycles...and if integrity of fuel tanks has been analysed via maintenance and techlog records?

Israel is absolutely silent on the whole matter. For those of us that have slightly deviated from military instructions (not Israeli, necessarily) when operating under their guidance, you know how accurate their equipment is. They saw and recorded the entire event.

With Israel's experience with the Sinai, they watch that airspace very closely.

Of course, the US knows as well from their various satellites monitoring in real time.

If it were a purely structural breakup, the major powers would have been clued in.

Judge the past by the actions in the present.