[TXnMA]

This is very preliminary, but a not-unlikely explanation is a small on-board explosive device in an aft lavatory or closet.

~~~~~~~

Notice (at right in this photo you posted)

the Airbus logo -- which is painted right before "A-321" in the photo of the intact aircraft (a/c) about halfway between the aft door and the aft-most window. (The fore-aft direction of the printing is reversed on the right side -- with the logo farthest aft.)

In this Russian A-321 internal layout,

That logo would be in the vicinity of what appears to be a closet or lavatory space. (The galley is on the left side opposite it...)

In your photo, a semicircular section of the fuselage above that area is missing, and the remaining, lower sidewall is bulged outward.

That section of the a/c apparently separated from the remainder at altitude. It hit the ground with minimal lateral motion -- and what there was, was rearward. (IOW, the aft section of the a/c was traveling slightly backward when it hit the ground. (Indication that it separated at altitude and "fluttered" down in a flat spin...)

If my analysis is correct, that section of the ac landed at a significant distance from the remainder of the fuselage.

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This is certainly no "take it to the bank" analysis but, based on this very fragmentary and sketchy evidence, all of this adds up to an initial suspicion of a small explosive device stowed in an aft luggage or lavatory space.

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If there is any "good" news from an incident like this, the "good news" is that the flight recorders are in that aft section of the a/c, and should be in excellent shape.

...just my $.02...

[Ready4Freddy]

“If there is any “good” news from an incident like this, the “good news” is that the flight recorders are in that aft section of the a/c, and should be in excellent shape. “

That, and the fact that there were apparently 3 empty seats...

[TXnMA]

Whoa! I just noticed this photo of the aft section of the a/c -- shot from the opposite side:

If anything, it reinforces my suspicion of an internal explosion in the aft galley/lavatory area...

Notice the left-side "A-321" I mentioned in my #47 (The Airbus logo is gone on this side...)

I don't see much, if any charring or "sooting", but the apparent hemispherical displacement of materials certainly suggests an internal explosion.

If this part of the a/c is separated spatially -- by a significant distance from the remainder of the a/c -- and if this portion is closer to the takeoff point, then I'd say the "aft-located bomb" scenario is a fairly safe bet...

[wrench]

Look at the photo in your post again. Look at the amount of debris that appears “flowing” toward the rear of the aircraft (wires, conduits, plastic snagged on door, door panel. etc.

The plane appears to be missing the rear pressure bulkhead, along with both horizontal stabilizers. The APU looks to be gone as well, it is aft of the pressure bulkhead.

This plane suffered a damaging tail strike several years ago. Failure years later from repaired tail strike damage brought down JAL flt 123 in 1985. And China Airlines Flight 611 in 2002. Both broke apart at altitude with no warning.

There have been other aircraft losses due to destructive decompression.

Here is one of the last pics of the plane so you can identify the parts shown in the crash photos:

http://cdn1.img.sputniknews.com/images/102938/92/1029389212.jpg