Plane Crash in Egypt - 224 Dead

[jwocky]

@KL-666: I doubt that is anywhere near the front of the plane for the very simple reason that the white part seen in the first picture some 35 meters away is the cockpit. It can be identified also in other pictures you find on the Internet, but unfortunately, I can't access pics from the Daily Mail right now (Firefox hangs with an ad they have in there). So if this Airbus hadn't two noses, one to each direction, this is definitively not the cockpit. Aside of that, you can also see in picture one, that the hull goes straight along behind this bulkhead. It is not dug in, nor ripped off, it is clearly visible at the bottom side (since it is flipped bottom up) of the part in the picture. If it would be the cockpit part, wouldn't there be a raising line up to where the cockpit windows were? I would also expect the nose cone connection wider than high (looking at the shape of an A 321) and I am pretty sure, there is no impact situation that could deform that part of a plane to this rounder shape, we see in the picture without breaking the inset bulkhead. So, since the cockpit was already found, since this bulkhead has the wrong shape to be the forward connection to the nose cone, since the nose cone was also already found, just a few steps away from the cockpit part, exactly 180 degrees from where this part points to and since there is obviously no open connection to a cable shaft (which it would need if there would be a high performance radar getting power through this bulkhead and send data back to the cockpit systems), what is it?

[HJ1an]

It would seem like the section just before the sheared off tail section. See the similar round-cornered square marking:

[HJ1an]

Oh wait. I just looked through more pictures. It IS the cockpit lower section. The marking is exactly there.

[jwocky]

And for the second part (I split that because the first post was about that bulkhead only, this is more about the chain of events and possible causes):

- KL-666's chain of events makes sense, but there is oen thing before, the question, what woudl cause such a sudden extreme elevator setting.

. it is unlikely, a human pilot would do it. He had no reason as far as we know, he just reached cruise altitude without problems and then the trouble started. If the information is correct, that he asked to be rerouted for an emergency landing instead of yelling, "mayday mayday, going down" he was probably not in such a steep uncontrollable flight attitude as such an elevator position would indicate.

- it is unlikely a computer would do this without a reason. Any autopilot reacts on inputs. So to make the computer do extreme things means, there had to be an extreme input of some kind.

- Thus, there has been something before the elevator went into such a position.

- it was not a bomb in the passenger cabin because such an explosion would have separated the tail at the area of the explosion or moved the weakest point to that part.

- it was not a structural failure in the pressurized part of the cabin, otherwise, explosive decompression would have been the consequence and at least deployment of the oxygen masks. That didn't happen or some of the masks would be strewn out over the debris field.

So the remaining questions are, what put the weakest point so far back and what happened that caused the extreme elevator position. I tend here a bit to abandon my initial theory that the APU maybe disintegrated as a possible result of bad maintenance because the bigger image, KL-666 posted shows no scatter shot impacts but a clear rip off at the rivet row. Which would be approximately the position where the forces of a tail strike would deform the fuselage. Means, for the moment, Vincent has obviously the better working theory.

[HJ1an]

In this video, you can that cockpit section (about 30secs). You can also see the horizontal stabilizers are completely missing from the tail section, which means they must have separated in the air long before

https://www.youtube.com/watch?v=Enb4soLA2Tw

[MIG29pilot]

- it was not a structural failure in the pressurized part of the cabin, otherwise, explosive decompression would have been the consequence and at least deployment of the oxygen masks. That didn't happen or some of the masks would be strewn out over the debris field.

The might not have had time--remember with the de Havilland Comet how the sudden decompression exploded the people's lungs and killed them instantly?

[jwocky]

That is a long time ago and the systems have been improved since then. So even with the people dead, the oxygen masks would have been deployed because the plane wouldn't know the people are already dead.

[KL-666]

Hello Jwocky,

It is good that we agree on the importance of the evidence how the metal has failed and that it implies certain forces at that point, and not other forces.

But i can not go into how the stabilizer got in a weird position, because i can not see the evidence. It is inside the tail section. The only thing that can be said is that the investigators will find that the elevators got into the weird position, and they will show us how it got there.

Hj1an said earlier that the main part of the stabilizers is behind the rear hinge. He assumed that the front would go up under the weight, if the jackscrew in the front failed. But weight is not as important as airflow. So the loose stabilizer would kind of follow the airflow.

But we need the front of the stabilizer down. So i am confident that the investigators will find the reason the front of the stabilizer was held down.

Kind regards, Vincent

[jwocky]

What if it wasn't the jackscrew that failed? What if it was the computer setting an extreme elevator setting. It would be at say 300 knots enough pressure to break up an already weakened fuselage. The problem with this is, radar data would for some moments show the plane climbing into stall and I haven't seen such data yet.
The question how a stabilizer or any other part from the outside can end up inside a part of the plane is relative easy. A plane that crashes in a relative shallow angle as the pictures indicate in this case, will not only slide but due to the heterogen ground also start to spin. We know already, that the forward part also flipped. Every time, any part standing out hits the ground in this process, the force is shifted against the fuselage. Since the fuselage is already weakened, by all means, it is already broken up, the construction of elevators, wings, stabilizers is stronger than the remaining structural integrity and thus, if the angle is steep enough can push into the fuselage. And the shorter the outlying part is, we talk, the higher is the probability to hit in such an angle.

[KL-666]

The stabilizer must have moved rather fast to have the inertia of the mass of the plane pull hard through the roof from the other end. There will not have been a climb, because the plane rips open before having the chance to climb.

If the stabilizer moved slow then the plane would simply climb within the structural limits of the aircraft. But in such case you will find counter action from the pilots. That did not happen on the boxes. Everything was normal until they suddenly stopped recording.

I have no idea how fast you can make the motors of the jackscrew move. Probably not fast, so we might have to think more in the direction of some sort of faillure.

Did anyone wonder how those Egyptians got so fast to the boxes? The boxes are in the tail section, behind the rear bulkhead , in front of the stabilizer at the right side. Videos circling the tail section show no entry from the outside. That leaves only one option, they walked into the stabilizer section from the front through the rear bulkhead. I do not suppose they would have cut a door in it. It is more reasonable to think the bulkhead was simply not there anymore.

Kind regards, Vincent