It was early morning, the sun was low to the West (rose about half an hour earlier). Visibility was good, aside from a few small clouds the entire Sinai peninsula was clear. No sandstorms or anything like that so visibility was also good.

Trying to quote post #172

A quick search via TinEye (think google for pictures)
https://www.tineye.com/search/34c62c...r=chrome-1.1.4

Gives this for the 'first scenes' from the Aviation Herald.
?????? ????? ???????? ???? ?????! - ???????

What i'm trying to point out is that even 'respected' websites and 'newspapers' can get it wrong, those pics are 2 years old and of a different airframe

Vinrouge, peekay4 - thanks for the info. Of course its the interrogation that initiates the transmission. Too much beer here methinks!

the BUK launcher..

http://i.huffpost.com/gen/1920815/th...ISSILE-570.jpg

Not easily moved about covertly or smuggled

It's actually a good question. Remember ADS-B is a "squitter" -- it does not require an interrogation before sending out a message!

Do you mean all photos with burned down wing and some horizontal stab (?) piece also burned?

22 seconds of ADS-B
 

22 seconds of ADS-B data tells me the majority of the airframe hung together for 4000 to 6000 feet of desent from the start of the "event".


If this indicates loss of tail past rear pressure bulkhead there may be little data to read out.

Yes the ones you posted on page 4 are from 2014

One thing I would note,

Where are both sides of the Horizontal Stab? Its certainly not on the shots with the vertical stab.

Would certainly explain the speed loss and height gain if the stab has gone in the cruise plus directional issues if a major part of the structure has failed, particularly stab pointing up into the airflow... aircraft would otherwise want to constantly nose down if the stab had gone completely.

I would be very interested in any recent maintainance/repairs of this area (rear bulkhead) as well as any historic damage.

Jet suffered tailstrike damage in 2001 for which it received repairs. If I were investigating, I would be spending a fair old amount of time looking for any cyclic metal fatigue and crack propagation around the rear bulkhead area, any pre-crash impact damage with the screwjacks...

Something similar happened with aft bulkhead damage caused by a vehicle on the Bagram 747 freighter crash a few years ago, pitch up, irrecoverable and uncontrollable stall.

this pic is pretty telling, especially the direction the fuselage material is bent (outwards)

Also, an aircraft with a freely floating stab will incur opposite control motion (if the elevators are controllable still) to the input. Interesting Gen regarding stab damage on this NTSB report: Aircraft Accident Report, AAR-15-01


RIP.

Debris Field appears
 

The third video down on this NBC story shows some wider angle shots of the crash site. Whilst not absolutely conclusive, they point to a relatively wide debris field but with major pieces still intact.

None of the major pieces appear to show the many small punctures associated with a fragmentation missile such as those clearly visible in MH17, and which would be typical of a missile required to reach this plane at its FL.

This would tentatively indicate some mid-air break up, but not due to not missile and so point towards some structural issue or major control surface failure, which is relatively consistent with the data we have from FR24 (lots of others have already expressed the caution that FR24 cannot be taken as fact)

Sad for the families, we pray for them and we all wait for the full inquiry results before we will really understand what happened. The rerouting of other aircraft a sensible precaution, whilst we all remain in doubt over the cause.

Egypt: Russian Passenger Plane With 224 Aboard Crashes in the Sinai - NBC News

The Sun rises in the EAST.

As would many of us, I suspect.

Bear in mind that 7 years elapsed between the JAL 747SR tailstrike and the Mount Osutaka crash.

Downlink Format 17
 

Does does downlink format 17 contain a "message sequence number" - an incrementing number - so that messages that are duplicated or missing can be detected and that out of order messages and be detected and re-ordered?

Just wondering as we do this in ground based systems used by the emergency services...

G

Telegraph quotes Egyptian officials saying that "Debris and bodies was spread over an area of between two and a half to just over three square miles." If true, there was at least some degree of midair disintegration, though it not necessarily the initial cause of the crash:

Russian plane crash: Egypt says it has found both black boxes of plane that crashed with 224 people on board - latest - Telegraph

of course. brain fart from me there, silly mistake.

PCs, NTP and FR24 receivers
 

While most PC clocks may not be highly accurate:

a) all of the PCs in my house are synchronised to NTP (I have my own NTP server)

b) most FR24 receivers are dedicated boxes - typically Raspberry Pi with an RTL dongle and *are* synchronised to NTP. Why dedicated boxes? because we leave them switched on 24/7/365.

G

Can someone confirm if the compulsory D-check was required prior to the china 747 incident? I'm intrigued as this is suspiciosly looking like it may be a bulk head failure - surely the D-check last year would of picked this up if it was fatigue or botched repair?

Being a A321 with its long backside, these seem prone to tail strikes more than any other in the family (19,20)

I imagine investigators have already checked the run way to ensure this bird didnt scrape its backside on its way in or out of its routes today? Having read about the Qatar flight which carried on after a T/S and taking out all the lights recently, if it does turn out they hit in this A321, it shows you how fortunate the Qatar guys were.

I was indeed - thanks for the correction. Brainfart moment.

Right Way Up asked:
I don't know about the accident airline's policies but, given the point of departure, it's possible that dive cylinders might have been on board. Standard precautions / procedures (depressurise the tank and preferably remove the valve - or open it) will prevent any problems but if proper precautions are not taken cylinders can be dangerous as this story shows;

Dive shop explosion sends tank shooting through parking lot | www.kirotv.com

Today's accident occurred near the top of the climb. The higher the pressure altitude, the greater the pressure differential if a dive cylinder has not been depressurised.

Dive cylinders that have been depressurised need to be inspected for corrosion before they can be re-used, so divers prefer to keep them at least slightly pressurised at all times to prevent corrosion. Airlines require dive cylinders to be depressurised before flight. Despite these opposing interests, qualified divers will be aware of the dangers and should respect the rules and airlines should enforce them. As a result, the chances of an accident are low but such an occurrence is not completely beyond the bounds of possibility.

Significant damage was caused to a Qantas 747 in 2008 when an oxygen cylinder exploded. This was part of the aircraft's systems but demonstrates what can happen when pressurised gas cylinders fail on board an aircraft;

Source: https://en.wikipedia.org/wiki/Qantas_Flight_30

See also; ASN Aircraft accident Boeing 747-438 VH-OJK Manila, Philippines

Re: Dive Tanks

Scuba tanks are pressurized to around 3000 psi, so dropping to an ambient pressure of, say, 3 psi wouldn't significantly increase the pressure differential.