Russian A321 Down in Egypt

[boestar]

Systems like that for FOQA, AMA etc are in fact far more complicated and require dedicated equipment on the aircraft to transmit the data. For an international airline this requires SATCOM in most cases for areas not covered by ground based communications.

That data by necessity is Proprietary in nature and should definitely not be seen by the general public in its raw form.

The ADS-B network depends on as many receivers as possible along the route to receive the transmitted data. This reduces the number of gaps in the data set and enables better analysis of the data so extrapolations can be made. Sample rates are too slow to be used as a definitive source of anything other than positional and speed data.

[dagger]

Now the US is saying the most likely cause was a bomb planted by ISIS or an ISIS affiliate or sympathizers. It's going on some of its own intel.

http://www.cnn.com/2015/11/04/africa/russian-plane-crash-egypt-sinai/index.html

So a major embarrassment for the Egyptians, since any bomb was almost certainly loaded on board by an airport worker or in baggage that was poorly screened.

[blues deville]

Now two countries not involved with the investigation are suggesting a bomb caused this crash ? Interesting.

[inchman]

Anybody remember WMD???

[dagger]

Now two countries not involved with the investigation are suggesting a bomb caused this crash ? Interesting.

You can imagine that the Egyptians don't want to admit to any suspicions along those lines. Bad for tourism, not just to the Red Sea but to anywhere in that country. The Russians might be loathe to admit they have inserted themselves into a new Chechen/Afghan adventure, and Putin will now drag them in deeper. The Iranians are suffering significant casualties trying to prop up the remnants of the Assad regime. I don't know who is doing all the killing on the sunni side - it's not all ISIS, but it is a quagmire.

This piece is a chilling warning that even the powerful are dying in Syria.

http://blogs.timesofisrael.com/soleimanis-curse/

[DEFCON]

The British have stopped flights and claim the bomb fuse was the pressure sensitive variety.

[conehead]

How would they know?

[dagger]

How would they know?

The US is citing intelligence picked up from monitoring extremists.

[conehead]

I dunno... nobody's talking too much about the tail-strike damage a while back. Remember the JAL 747 pressure bulkhead blow-out? That was caused by the failure of a previous repair, and this incident could be a repeat.

[blues deville]

I dunno... nobody's talking too much about the tail-strike damage a while back. Remember the JAL 747 pressure bulkhead blow-out? That was caused by the failure of a previous repair, and this incident could be a repeat.

CNN was talking about this yesterday but the now the bomb theory is headline news.

Not a crash expert by any means but the tail wreckage appears to be a clean break at the top of the fuselage with no visible burn marks. The FDR and CVR should produce more accurate details of this tragic event.

[boestar]

They want it to be a bomb. That would give more excuses to increase military presence in the region. At this point no one even knows who is fighting who. It's like a free for all.

A bomb would allow the placement of direct blame and actually give the enemy a face.

[Mitch Cronin]

The tail broke off well forward of the aft pressure bulkhead.

[deicer]

A question I saw on another forum is that with it being almost a week since the crash, why is there no mention of explosive residue when there is so much of the fuselage available?

[J.O.]

The tail broke off well forward of the aft pressure bulkhead.

That's true Mitch but that doesn't necessarily mean that a compromised bulkhead couldn't have started the event. It would all depend on how the break-up happened.

[DEFCON]

This morning the BBC reported the event wasn't a repeat of the JAL crash.

[boestar]

Remember the Hawaiian airlines "convertible"? That was an un-noticed condition of corrosion that led to the loss of a significant portion of the upper fuselage. It happens.

If there was a previous tail strike then it is possible that the joint from the mid fuselage section to the aft was compromised. Possibly

A bomb in that location could also cause a failure of the joint in that section. Possibly.

A missile could have struck the fuselage at that point. Possibly.

Proof is the only missing piece.

[Woody Pusher]

It is now being reported out of Russia, that following the recovery of the DFDR data, the readout provided normal data parameters for the flight until the recording stopped.

No time for end of recording has been provided, but I suspect that it ceased within a few milliseconds of 04:13:13UTC.

Apparently, the CVR was not able to be decoded, and specialist Honeywell assistance may be required to recover the raw data. Though, if cockpit conversation was normal, there will be nothing of further interest as it will have ceased at exactly the same time as the DFDR.

[inchman]

Given the location of the breach, I would suggest that the feed would stop instantaneously regardless as to the cause, and before there was any recording of parameters that might provide real insight as to the cause... everything normal then no signal. I think the cause will have to be found from the clues left on the empennage. Fortunately (or unfortunately) the tail separated so that it did not burn with the rest of the aircraft, allowing some definition. Hopefully they won't "drag it over the stern" like Indonesia did with the remains of AirAsia.

I don't know why they keep putting the DFDRs and CVRs so far from the source of the data.

[Kip Powick]

Given the location of the breach, I would suggest that the feed would stop instantaneously regardless as to the cause, and before there was any recording of parameters that might provide real insight as to the cause... everything normal then no signal. I think the cause will have to be found from the clues left on the empennage. Fortunately (or unfortunately) the tail separated so that it did not burn with the rest of the aircraft, allowing some definition. Hopefully they won't "drag it over the stern" like Indonesia did with the remains of AirAsia.

I don't know why they keep putting the DFDRs and CVRs so far from the source of the data.

Surely you've heard that old expression..."Sit in the tail...that's the first part they find" !!!

I am assuming that the DVR and CVR are located in that part of the aircraft that is "normally" the least bit damaged should the unfortunate aircraft turn into a lawn dart....not many aircraft back into the ground, mountains etc.

[Don Hudson]

Hi inchman; re, "I don't know why they keep putting the DFDRs and CVRs so far from the source of the data."

Well, I think you do know why, but I understand the asking of the question.

But in terms of moving recorders closer to the "source(s)" of the data, why - what is the problem being solved? Is it their physical location or data inaccuracies over long distances?

In electric airplanes, (B777, B787, Airbus), the flight controls are a long way from their source data, (the inputs from CC's/SS's and autoflight systems in the MEC/EE Bay) and they work just fine over the same distances.

In my view, there is no case to be made in this accident or any other event including AF447 & MH17 that supports a change. A more effective change to pursue could be the electrical supply to the recorders, but then they must have something to record. If the nerves are cut, communication of all kinds ceases. However, at least the CVR should have this facility for aircraft sound & voice recording.

The technical and business cases would need an urgent imperative and even then it would take years and cost the airlines millions. The case for deployable SSFDRs/SSCVRs or full-time satellite transmission of every aircraft's flight data can't be made, so actually moving the location of the crash recorders "to keep them closer to the sources of data" can't/won't be made. It took years and years for the FAA just to approve an additional/alternate location for a combined DFDR/CVR near the cockpit. It certainly won't happen in Canada.

All these are entirely different from QAR installations, (I know you know this...just clarifying for all).

FAR 1457

. . .

(1) Except as provided in paragraph
(e)(2) of this section, the recorder container
must be located as far aft as
practicable, but need not be outside of
the pressurized compartment, and may
not be located where aft-mounted engines
may crush the container during
impact.
(2) If two separate combination digital
flight data recorder and cockpit
voice recorder units are installed instead
of one cockpit voice recorder and
one digital flight data recorder, the
combination unit that is installed to
comply with the cockpit voice recorder
requirements may be located near the
cockpit..

[CD]

The technical and business cases would need an urgent imperative and even then it would take years and cost the airlines millions. The case for deployable SSFDRs/SSCVRs or full-time satellite transmission of every aircraft's flight data can't be made, so actually moving the location of the crash recorders "to keep them closer to the sources of data" can't/won't be made. It took years and years for the FAA just to approve an additional/alternate location for a combined DFDR/CVR near the cockpit. It certainly won't happen in Canada.

All these are entirely different from QAR installations, (I know you know this...just clarifying for all).

FAR 1457

. . .

(1) Except as provided in paragraph

(e)(2) of this section, the recorder container

must be located as far aft as

practicable, but need not be outside of

the pressurized compartment, and may

not be located where aft-mounted engines

may crush the container during

impact.

(2) If two separate combination digital

flight data recorder and cockpit

voice recorder units are installed instead

of one cockpit voice recorder and

one digital flight data recorder, the

combination unit that is installed to

comply with the cockpit voice recorder

requirements may be located near the

cockpit..

Hi Don...

I wasn't sure what you were referring to with respect to "it" not happening in Canada. However, if it is in reference to alternate locations for a combined DFDR/CVR, we have the same requirements as the U.S.:

525.1457 Cockpit Voice Recorders

(e) The record container must be located and mounted to minimise the probability of rupture of the container as a result of crash impact and consequent heat damage to the recorder from fire.

(1) Except as provided in (e)(2) of this section, the recorder container must be located as far aft as practicable, but need not be outside of the pressurised compartment, and must not be located where aft-mounted engines may crush the container during impact.

(2) If two separate combination digital flight data recorder and cockpit voice recorder units are installed instead of one cockpit voice recorder and one digital flight data recorder, the combination unit that is installed to comply with the cockpit voice recorder requirements may be located near the cockpit.

[DEFCON]

Has the tail-plane been located and if so, where was it found relative to the other sections of the fuselage?

The missing tail-plane structure appears to have been 'torn' from the aircraft at some point during the crash sequence, which is a feature of the wreckage that's more difficult to rationalize, or incorporate within the bomb theory.

With this in mind, I have an Airbus related question; if the FCS enters Direct Law, can the manual trim system move the tail-plane surfaces fast enough to allow a pilot to respond properly and smoothly during an aggressive excursion from controlled flight, or is it just as likely to expect structural overloads to be introduced during the recovery attempt and the back of the bird broken?

[J.O.]

The main piece of the tail has been shown in photos, apparently found some 2.5 km away from the main wreckage. Nowhere in any of the photos I've seen has there been an image of the horizontal stab or elevator.

[dagger]

The Russians are suspending flights to Egypt. And the BBC, citing unnamed UK intelligence sources, says a bomb may have been smuggled on board by an airport worker.

http://www.cnn.com/2015/11/06/middleeast/russian-plane-crash-egypt-sinai/index.html

[Don Hudson]

CD, thank you very much for pointing that out. I actually hadn't look in the CARS for a long time and did not know that an alternate place was permitted so made the ass-umption! ;-)

The question regarding "why move things?" remains tho' . What is it about this accident that has caused the question to be raised?

The twin notions of deployable DFDRs and satellite transmission of real-time data arose in the case of AF447 and MH17. But those are the only two recent losses that I recall in which such a system may have assisted understanding what happened. There is only one case in which the recorders have not been recovered.

The industry must sustain the costs of creating, certifying, installing, sustaining such new recording systems. In practise the present system works well, overall. There are questions regarding power sources but that only applies when the data cables remain intact, (hence the reason for prioritizing self-contained power sources for the SSCVR as the data is uninterruptable through loss of "signal").