BREAKING NEWS: airliner missing within Egyptian FIR

[Ka-2b Pilot]

If an explosive decompression occurred at the time the first body was ejected it could have disabled both pilots before they could don oxygen masks. The aircraft being on autopilot may continue as before for a short time until damage to the stabilizers caused by other exiting equipment resulted in them breaking away. This could account for the body being found several miles away. Some evidence of this occuring should be on the FDR.

[Pontius Navigator]

PS, first pictures both discussed in detail including possible cut her splatter on the back ground part.

[fyrefli]

The message from Russia was less conciliatory as Cameron was warned during a 10-minute phone call with president Vladimir Putin not to jump to conclusions that the disaster was caused by a bomb.

Downing Street stressed it was “cordial” exchange but a statement from the Kremlin afterwards said: “Vladimir Putin stressed that assessment of the causes of the crash should be based on the data that would become available in the course of the official investigation that is currently under way.”

Asked whether Putin had expressed any criticism about British actions, Cameron’s spokeswoman said: “The president underlined that all countries should wait for the investigations to be completed. The PM was very clear that he would be driven by what would be right for the safety of British citizens and we were right to take the actions that we did.”

Earlier, a Russian foreign ministry spokeswoman said it was “truly shocking” that it appeared the UK had not shared intelligence with Russia if it had any suggesting it was caused by a bomb.

From Airlines to return British holidaymakers from Egypt without hold luggage | World news | The Guardian

Apologies if anyone else has posted this part of the article. If so, I've missed it.

[Smott999]

How disabling to the pilots might be a sudden pitch down? with enough neg Gs or prolonged negG, would they even be able to don a mask, never mind manage the aircraft?

[Kulverstukas]

FDR shows totally normal flight parameters until sudden loss of any signal.

This lead me to conclusion that VS (with, possible all other tail structures) was lost first and HS separates only after.

[Prada]

tail

FDR shows totally normal flight parameters until sudden loss of any signal.

thats bad. It will be much harder to solve that mytery.

At least we know connection to FDR was severed with initial event.

Do we know where exactly power cables to FDR run? on the right side? bottom?

[Bertie Bonkers]

Flight recorders

Going way back to Kulverstuka's photo at #1004 of the HS & jackscrew & seeing how close the flight recorders are mounted to the front edge of the HS. If the jackscrew failed & the front end of the HS went straight down, would it be close enough take out the connections on the back of the recorders?

[silvertate]

Tailstrike...
Just curious, did the tower see it and give your FD crew an alert over the radio?

No, they had no idea. Had to explain three times why we wanted to return.

"You have emergency...? " "No". "Why you return?". etc, etc, etc and etc. I did mention 'for a cup of coffee' in desperation, which probably complicated matters.

[Kulverstukas]

Do we know where exactly power cables to FDR run? on the right side? bottom?

I get it as signal cables was broken. I hope there is some kind of backup batteries inside recorders.

[metro301]

If the input cable was broken, it would not require a battery back up as there is no information to record.

[Ka-2b Pilot]

Not sure on FDR but CVR only has battery for pinger (as I recall from 10 years ago). These are Honeywell which I am not familiar with.

[G-CPTN]

With the latest announcement about the FDR being normal until the event, it seems that neither the FDR nor the CVR will provide any useful information, other than that the initial event involved severing the cables to the recorders.

This could be an event that, initially, just severed the cables (along with associated structural damage) and that subsequent break-up events were 'not recorded' rather than being simultaneous.

What could sever the recorder cables (first).

[oleostrut]

"Do we know where exactly power cables to FDR run? on the right side? bottom? "

From the post linked below, they appear to run along the top right of the fuselage. Not just power, but data cables as well.






http://www.pprune.org/rumours-news/5...st9169622.html

[Ka-2b Pilot]

An explosion or a fracture in the area of the cable run through the fuselage will likely cause damage to said cables.

[G-CPTN]

It would seem to be necessary that the interruption that caused the severing of the recorder cables was, by its nature 'abrupt' (instantaneous) rather than a slow 'tearing' event (which would have prompted changes in the flight parameters).
Any bomb would have had to be precisely located (as mentioned above) and any structural failure 'catastrophic'.

(These assumptions rely on the announcements being correct, of course.)

The 'event' that severed the recorder cables also had to be serious enough to result in break-up of the aircraft structure (rather than just severing the cables).

[wilyflier]

1004 kulverstukas

[QUOTE=Kulverstukas;9169622]I just leave it here - HS part of tailcone from inside:

HS servo


CVR/FDR left, HS screw and HS center
[/QUOTE
In your second photo of Jackscrew, do i see two red components upper left of picture? CVR?+ FDR? So close to the action?

[VinRouge]

For those questioning depressurization, having experienced a 25 and 40K chamber run, the times of useful conciousness, in my experience, were far in excess the published figures. However, a bit of adrenalin probably less. At 30K, I would estimate TOC to be measured in minutes; although a bit giggly and getting a bit of a headache, I knew where I was and what I was doing. I could put my own mask on after 60 seconds when asked, although my writing went to rats.

I think any pilot in that circumstance would be focussing on company or aircraft specific procedures, typically one person flying the aircraft, whilst another dons the mask. Hand over control, repeat. If there was the sort of short period oscillation going on that has been seen in the mode S, it would have been a very difficult situation to manage. I think personally, I would be trying my damn best to disagnose the situation, through warning and caution or ECAM, trying to get the passenger area secure, communicating if you had chance. The fact that the aircraft seems to have undergone significant upset to the fight path without ATC communication is indicative of how serious it got, and quickly. I hope they find the QAR disks as it will have a wealth of information in there.

I dare say the engineers will have fracture analysts looking at the back end to figure out if this was fatigue related or something more sinister.

[HarryMann]

Originally Posted by Lonewolf_50

Prada:

based on the lines that you drew where you show what look to be failure lines ..

If for example only one half of the HS failed/tore off, would the instant imbalance of downward forces from the other half of the HS create enough torsion (twist/torque) on a vertical stab and tail to make it fail along that line/zone ... with the aft bulkhead being strong enough to resist it?

My guess is "no" because the area around the HS has to be a structurally strong part of the aircraft due to the loads the HS puts on it all the time in flight. However, I am doing a back of the napkin guess, and maybe load paths would make that a possibility if the back end experienced a twisting type of load.

Depends entirely on the airspeed and angle of attack of the HS. If the HS is at its normal nominally low AoA then probably no it wouldnt fail.
As pointed out earlier, if not constrained (free flying tailcone) then the forces wouldn't be heavily reacted and the surface (s) just decelerate

[Ka-2b Pilot]

@VinRouge, what you say is true for a fit, young person, though may be degraded for an older not so fit person. I have also been in a chamber, but only to 30K I think. In the case of an explosive decompression (faster than the human body can compensate) the lungs may be instantly damaged to the extent that you may not be able to breathe anyway. A rapid decompression should be survivable.

[flt001]

UK Intelligence

"A specific piece of 'signals intelligence' picked up at the GCHQ listening station convinced Prime Minister David Cameron that a Russian plane which crashed in Egypt was brought down by a bomb, ITV News understands."

'Specific piece of intelligence' led government to believe there was bomb on board Russian plane - ITV News