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-   -   MH17 down near Donetsk (https://www.pprune.org/rumours-news/543733-mh17-down-near-donetsk.html)

OleOle 11th August 2014 08:03

The wind profile may help to get an idea of the drift of falling debris:

34731 URRR Rostov-Na-Donu Sounding


Can't say much about the accuracy.

FritsHoogsteden 11th August 2014 12:05

The dutch safety council sais it needs more time to investigate MH17 but it will not investigate who's quilty.
Is that standard/normal? Does anyone know?

1978 11th August 2014 14:20

Based on the flight path given by flightradar24, on a heading of 118 for the last 5 minutes, MH17 was flying towards TAMAK with only 30 nm to go and definately not towards Rostov (RND). Could be there was communication about an alternative flight path and it would certainly be interesting to find out if there was more to it...

DaveReidUK 11th August 2014 14:22


The dutch safety council sais it needs more time to investigate MH17 but it will not investigate who's quilty.
Is that standard/normal? Does anyone know?
Any AIB's job is to establish the probable cause of an incident/accident, and to make any safety recommendations it sees fit.

AIBs do not seek to apportion blame or guilt.

Lena.Kiev 11th August 2014 14:27


Originally Posted by 1978 (Post 8603467)
Based on the flight path given by flightradar24, on a heading of 118 for the last 5 minutes, MH17 was flying towards TAMAK

On the RND civilian radar playback, heading from TAMAK to MH17 was 300, i.e. 2° difference. The angle is visible when the person performing the playback applies measurement tool.

1978 11th August 2014 14:37

If it were going to RND the heading of the plane would have been more like 135.

mennie 12th August 2014 08:41

There is not much information about this but the Public Prosecution Office (Openbaar Ministerie) is conducting a criminal investigation into the plane crash.

Source:
OM onderzoekt moord en oorlogsmisdaden bij MH17 - AMSTERDAM - PAROOL

KatSLF 12th August 2014 09:22


The bit that gets overlooked is the fact that the heading for the airway should have been about 106. The reason it's larger is because MH17 offset from the airway for a while and therefore had to fly a greater heading to reach TAMAK.

So, you're saying it was earlier heading more directly east? that would place it north of where it should be. Would that be enough deviation for them to scramble some fighters up to tell them to get back in their right lane? maybe not scramble, but if they already had some in the air?

BOAC 12th August 2014 09:26

One assumes the CVR and FDR will contain reference to any such deviation.

blackbird69 13th August 2014 10:22

I have a serious issue with what here and in many forums is considered elementary:

That explosive decompression would automaticaly lead to in flight break-up.

This is more exception than rule. In most cases the plane remains intact, even on higher altitude.

In this case the total area of holes would be the size of a cargo door. Not exceptionally large.

So what caused the breakup? :confused:

LiveryMan 13th August 2014 10:38


Originally Posted by blackbird69
So what caused the breakup?

I'd imagine it had something to do with the shrapnel punching large holes and dozens of smaller ones in the flightdeck skin and possible weakening structural members that failed when put under load from the air stream screaming into the fuselage at 300 odd knots.

Just a hunch mind you!

OleOle 13th August 2014 12:01

Apparently the part that was closest to the detonation and has most shrapnel traces - the cockpit - came down in almost one piece.

toaddy 13th August 2014 12:46

Is it conceivable that with electrical wiring and possibly hydraulics destroyed that some of the control surfaces could be driven into the stops? Even if that is possible, could it cause the plane to break up at cruise speed?

SAMPUBLIUS 13th August 2014 13:50

what caused the breakup ?
 

So what caused the breakup?
crude example- at 60 mph, put your hand out the window. face palm down like an airplane wing. Now twist palm 90 degrees so palm faces forward.

feel the difference ? Now multiply that force by 8 to 10 and thats for a small area of say 25 square inches. Now multiply that by say 800 for a approx body diameter closed tube into the ' wind "

In addition, plane losing control may dive or nose up or twist or turn

Forces above 3 to 4 g would exceed max design overload - ultimate - in a few seconds or less.

KatSLF 13th August 2014 15:53


That explosive decompression would automaticaly lead to in flight break-up.

This is more exception than rule
It wasn't just a simple decompression. There was also a big blast wave from the missile detonation, as well as shrapnel from it.

There were perforations which a "normal" decompression would not have. So it would open up along those like tearing toilet paper along perforations. There is that one piece often photographed, which was just behind the cockpit, curled back before it tore off. It would loosen the next piece it is attached to, before totally separating. That gives the next piece a protruding edge (and distorted profile) to start peeling back from.

The cockpit came down more or less in one piece because it has a triple strengthened frame and skin (to resist bird strikes and hail). And the main fuselage damage started behind the cockpit, so the floor and right side still held it on, while the business class port wall and roof ripped off in one joined piece. The starboard wall came off later, and the floor twisted and broke next. With the plane "scooping" wind, port wing control surfaces damaged and port engine not running, it would have to be falling in a sharply banked dive, probably the first half of a spin dive. that would be enough Gs to separate the floor and drop the cockpit.

The sudden change of centre of gravity, coupled with more "scooping" would have levelled it off a bit and certainly turned it to port about 80 degrees. Possibly adding a last "flick" to the tail that would be the last straw/Gforce to break up the rear into 2 sections. It all broke roughly along the lines where the sections are joined together, as these are the weakest spots. Wing tips fell off, either shaken loose or being hit by other pieces of debris.

With 1 1/2 wings and one dead engine, the heaviest strongest wing section then continued on to crash at a flat low angle, probably no faster than a fast landing speed (it didn't go in deep and it didn't leave a skid furrow).

Oh and another thing -- in decompressions where the plane remained intact and flyable, there always were PILOTS left to fly it and controls left to take their commands. Here the pilots and the avionics were the first to go.

infrequentflyer789 13th August 2014 16:30


Originally Posted by OleOle (Post 8606389)
Apparently the part that was closest to the detonation and has most shrapnel traces - the cockpit - came down in almost one piece.

I would be wary of assuming the cockpit was closest point. We don't have (I think) much in the way of info or wreckage photos about the port side behind the cockpit for a start, maybe it was shredded even smaller.

The Paris Match article that was quoted earlier in the thread (Exclusif-Notre enquête sur les lieux du crash. Comment le MH17 a été abattu - Paris Match) is one of the best looking analysis I have seen so far, and concludes that the detonation point was next to business class. Not sure they are exactly right, but it is worth reading (google translate will do a passable job for non french speakers, or poor/rusty/lazy french speakers like me).

SKS777FLYER 13th August 2014 19:07

LE MISSILE A EXPLOSÉ DERRIÈRE LE SIÈGE 5A, missile exploded behind seat 5A


I pray (is that permitted to be expressed here?) that my post be within the limits allowed mere aviation mortals....that the words communicated fall within the permissible correct and approved narrative, so help me PPRUNE.:ok:

short bus 13th August 2014 22:16

I think it is possible the rear steel rocket part of the missle impacted somewhere into (through?) MH17 as well. That tree sized piece moving at a very high velocity would do significant damage.

anonymousdefender 14th August 2014 02:05


LE MISSILE A EXPLOSÉ DERRIÈRE LE SIÈGE 5A
Fow anyone who dont know french what talking about this source?
If something hit a plane near seat No 5A then Seeker and Fuse can continue fly after detonation of warhead (which hit by multiple strike elements a cabin).
Then it another fact about launch site Snezhnoe.

Lena.Kiev 14th August 2014 06:02


Originally Posted by short bus (Post 8607102)
I think it is possible the rear steel rocket part of the missle impacted somewhere into (through?) MH17 as well. That tree sized piece moving at a very high velocity would do significant damage.

I suspect that it made the gash in the left wingtip near the "safety line attach point" red circle. Not significant damage, but a trace of missile trajectory (from the front).

https://secure.flickr.com/photos/jer...s/14714323731/
http://aviaforum.ru/showpost.php?p=1593510

blackbird69 14th August 2014 10:58

katSLF wrote:
Oh and another thing -- in decompressions where the plane remained intact and flyable, there always were PILOTS left to fly it and controls left to take their commands. Here the pilots and the avionics were the first to go.

This is not always the case. TWA800 and Hughes Airwest 709 remained in one piece while the cockpit was gone. In fact, the investigators of Pan Am 103 (lockerby) had poblems to explain why the rear section broke up in many pieces. So they said that broken cables gave last seconds imput etc during cockpit section separation. The 777 has no cable steering in that sense, so the steering surfaces would end in a locked beutral position.

blackbird69 14th August 2014 11:22

SAMPUBLIUS wrote
crude example- at 60 mph, put your hand out the window. face palm down like an airplane wing. Now twist palm 90 degrees so palm faces forward.

feel the difference ? Now multiply that force by 8 to 10 and thats for a small area of say 25 square inches. Now multiply that by say 800 for a approx body diameter closed tube into the ' wind "

In addition, plane losing control may dive or nose up or twist or turn

Forces above 3 to 4 g would exceed max design overload - ultimate - in a few seconds or less.


The concept of airodynamic drag is known to me. Don't forget that the pressure at 33000 feet is only 1/5th of ground pressure.

The lockerby report concluded also that the pressure on the back section even as an open tube would not cause the structure to fail.

In your terms: The issue is how the hand changed from horizontal to vertical.

Mahatma Kote 14th August 2014 12:11

Blackbird69 said


The lockerby report concluded also that the pressure on the back section even as an open tube would not cause the structure to fail.
Simple pressure probably won't cause complete structural failure - though there are quite a few accidents where differential pressure has caused an ultimate failure of the aircraft or significant damage. Examples are

Turkish Airlines Flight 981 - lost cargo door
American Airline Flight 96 - lost cargo door

On similar major incidents to MH17, the disruptive event caused immediate separation of part of the aircraft and subsequent disintegration of the rest due to aerodynamic overloads.

PA-103 (Lockerbie)
TWA-800 ( US)

Incidentally, in both of the above incidents, the main part of the aircraft continued flying until ground impact or detachment of wings etc.

MH17 appears to have done the same thing with late detachment of the tail after loss of the cockpit and 1st class cabin early on.

blackbird69 14th August 2014 13:26

Mahatma Kote wrote:

Simple pressure probably won't cause complete structural failure - though there are quite a few accidents where differential pressure has caused an ultimate failure of the aircraft or significant damage. Examples are

Turkish Airlines Flight 981 - lost cargo door
American Airline Flight 96 - lost cargo door

These accident clearly came to my mind. But remember that regulations have changed after these accidents because the cabin floor of the DC-10 was considered too weak. Both planes stayed intact. AA 96 landed safely. For completeness I mention United Air 811, also landed safely, after loosing forward cargo door (And that is a large door).


Mahatma Kote wrote:
On similar major incidents to MH17, the disruptive event caused immediate separation of part of the aircraft and subsequent disintegration of the rest due to aerodynamic overloads.


This is suspected, but not explained - which is exactly my point.

Mahatma Kote wrote:
PA-103 (Lockerbie)
TWA-800 ( US)

Incidentally, in both of the above incidents, the main part of the aircraft continued flying until ground impact or detachment of wings etc.

MH17 appears to have done the same thing with late detachment of the tail after loss of the cockpit and 1st class cabin early on.

PA 103 main part disintegrated on high altitude.
TWA800 main part disintegrated on impact.

Clearly not the same. Only other plane to disintegrate on high altitude is china airlines 611. That took 10 - 15 s.

Differences between TWA800 and PA103:
TWA800: 18000 feet, no damage to engines or tail during separation.
PA 103: 31000 feet. During separation the front section folded to the right and hit the nr 3 engine, which was detached. Also debris damaged both horizontal stabilizers.
One strange thing about the break up is that 3 of the landing gears and wheel wells and the aft cargo hold stayed together. Strange because the 747 likes to break just after the body landing gear wheel well (SQ0600, klm tenerife and others).

From MH17 evidence so far it looks most likely that the missile exploded in front of the left side of the cockpit. It caused the aircraft skin to blacken and deform by the blast, next to numerous holes in the skin, probably all cockpit windows destroyed, killing crew and ravaging avionics. Result decompression (doubt if this is explosive decompression. Calculations show so far it still took several seconds before cabin pressure was gone).

And then what?

OleOle 14th August 2014 15:33


Originally Posted by Green Guard (Post 8607916)
any news or rumors about...when the red boxes will be read out and published ?


The team's efforts will initially focus on the report of preliminary findings, which the Dutch Safety Board aims to publish in a few weeks' time.
Dutch Safety Board | Investigations & Publication | Investigation crash MH17, 17 July 2014

1978 15th August 2014 12:47


By blackbird69: "Result decompression (doubt if this is explosive decompression. Calculations show so far it still took several seconds before cabin pressure was gone)."
Where are you getting this from? Doesn't make sense to me and at the moment there doesn't seem to be enough information to do these "calculations"?!

KatSLF 15th August 2014 17:47

The shrapnel is preceded by a blast wave travelling around say mach 4. This is very high pressure, so for a moment there is higher pressure outside, so it doesn't decompress. Then the wave passes, it decompresses by rolling and curling back the panels along the perforations. It does not need to be explosive to rip up the cabin, because of the shrapnel holes. Twisting, banking, awing, diving, parts ripping of, port engine ingesting its own fan.... a lot of G forces in a lot of directions it was never designed for ....enough to break along ALL the section join lines. Fast or slow,who really will ever know? but there's only 2 or 3 seconds difference between the two speeds, so its moot.

Pontius Navigator 15th August 2014 19:20

If you want to see what happens when a SAM explodes near an aircraft look at this clip.

Nike Missile Destroys B-29 Bomber | Military.com

around 2.10 the missile hits. The destruction is immediate and the aircraft rotation tells its own story.

SAMPUBLIUS 16th August 2014 04:19

777 cable steering
 

The 777 has no cable steering in that sense,
Not quite true. The 777 while normally FBW does have minimal cable backup for minimally suffficient flight control when everything else goes bonkers. But in this case, cables would not have made much difference re the final result .:ugh:

1978 17th August 2014 14:46

@blackbird69:
Thanks. In the investigation of Korean 007 they did actually use such calculations to estimate initial damage to the fuselage! wikipedia/KE007
It would seem MH17 took more of a direct hit and initial damage would have been greater? Comparable to that in other similar major decompression accidents ?
Either way the plane was probably doomed after the initial hit and we will have to wait for the investigation to know a bit more.

blackbird69 18th August 2014 22:34

1978 wrote:
Thanks. In the investigation of Korean 007 they did actually use such calculations to estimate initial damage to the fuselage! wikipedia/KE007
It would seem MH17 took more of a direct hit and initial damage would have been greater? Comparable to that in other similar major decompression accidents ?


KAL007 was hit by a R-98 AAM, 40 kg fragmentation. The surface of the hole(s) is surprisingly small. Maybe it hit the cabin after the pressure bulkhead.

MH17 was hit by a larger warhead. The cockpit was immediately evacuated, and there could have been large stress on the two bulkheads between cockpit and cabin.

blackbird69 18th August 2014 22:47

anonymousdefender wrote

Quote:
LE MISSILE A EXPLOSÉ DERRIÈRE LE SIÈGE 5A
Fow anyone who dont know french what talking about this source?
If something hit a plane near seat No 5A then Seeker and Fuse can continue fly after detonation of warhead (which hit by multiple strike elements a cabin).
Then it another fact about launch site Snezhnoe.


The seat plan of malaysian Airlines 777-200 can be found here:
SeatGuru Seat Map Malaysia Airlines Boeing 777-200 (772)

Seat 5A is on the first row after the L2 door.
https://www.flickr.com/photos/jeroen...57645908125941
This is the L2 door including one window after it. No sign of missile impact here.

I don't know why PM thinks the missile entered here. The only reason I can imagine is that the forward section including cockpit has a length just very close to this door. This piece of wreckage is puzzling because it is bend so severely especially near the floor, that I suspect the forward section folded here to the left before it broke away.

So far for the 5A missile hit

KatSLF 19th August 2014 00:25

Is the seat number written on the actual seat??

I never understood where Paris Match got the Seat 5A from. They WERE on the scene before the bodies were removed, and saw a badly injured woman;s body, still in her seat, from the business class setion. But I don't know where they get 5A from.
The section in the image you linked has 3 or 4 small holes high up in the roof area, about level with the front edge of the door (visible in other images). Nothing else. The bending you see happened on ground impact.

The section in front of that door is missing, or fell flat and is covered in other debris. It is not possible to guess at what shrapnel damage is on it. But going on what is on the cockpit, this are must have received some damage, too, and people sitting near here may have been hit. This would be rows 1 to 4.

oldoberon 19th August 2014 09:51

What is the exact status of the wreckage, have the crash investigators been able to visit regularly, have any key bits of wreckage been removed and secured (ie the cockpit area).

if not is anyone there 24/7 observing/securing the various sites, it seems to have gone very quiet.

Lena.Kiev 19th August 2014 10:02

It's a war zone.

Latest map:
http://mediarnbo.org/wp-content/uplo...4/08/19-08.jpg
Red explosion icons - battlezones;
Orange explosion with broken plane icon - the crash site.

oldoberon 19th August 2014 12:37

Ta yep a war zone, but that still doesn't tell me if anyone has taken responsibility to secure the crash sites.

Volume 19th August 2014 14:55

Isn´t it time to get some press release from the Netherlands?
Preliminary autopsy results (shrapnel found in bodies)?
Preliminary seat asignment of the bodies recovered and missing?
Preliminary CVR analysis?
Preliminary ATC recording analysis?

Are there really no facts available by now to base further discussion on?
Compared to other accidents there is a lot of silence currently.

Hotel Tango 19th August 2014 15:00


Compared to other accidents there is a lot of silence currently.
Since this must be a criminal investigation as well as a crash investigation, I would say that there are very good reasons to keep things out of the public domain for the present at least.

tdracer 19th August 2014 16:40


Compared to other accidents there is a lot of silence currently.
Generally, early information releases during crash investigations are either to:
a) indicate that the initial findings are that there is not an unsafe condition that could affect other aircraft or
b) there is a potential unsafe condition and they recommend steps to alleviate the safety concerns (inspections, etc.)
In this case, there is pretty universal agreement that the airplane was shot down. So there isn't much justification for early information release simply to alleviate potential safety concerns.

KatSLF 19th August 2014 17:39

The recovery teams with the sniffer dogs had to go, there was no point sticking round, as there was to much fighting in the area. They hope they got a piece of everyone but they know there's some who may never be found.
The plan was to send investigators after the recovery was done. They haven't said, but if they had any sense they would have picked up and kept smaller pieces that looked potentially useful.

I had a picture last week of the burn field where the engines fell. The 8 - 12 inches fine broken small rubble they were standing on has been cleared, and they're on almost bare earth now. Guess the farmer wants his field back. Maybe they're dumping the bits into big drums, for lack of anything better to do, then they can be shipped back.

That port engine is worth bringing back. It is the most likely piece to have collected shrapnel that would still be there. In thinner bits it would have gone through and fallen out. They only need 1 or 2 to analyse. It is no likely to show who pushed the button .


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