A fire in the engine is not enough to turn a 737 into a huge burning fireball that crashes within 20 seconds.

Regarding the missile theory: if it was a missle, it was probably accidential. The majority of passengers on board were Iranian citizens.

> Regarding the missile theory: if it was a missle, it was probably accidential. The majority of passengers on board were Iranian citizens.

Unless it was a non-Iranian missile, or a rogue actor.

(At this point, it's all speculation)

Unless the engine blades detaching ripped apart something critical, as happened several times on different aircraft, and crucially, twice on exactly this model with this engine from similar manufactuer time.

Remember Stuxnet?

Pretty sure russian/chinese SAMs don’t run windows

What makes you pretty sure of that?

* Most of them were made before it was even a thing

* Precisely for reason above

> turn a 737 into a huge burning fireball

From a suggested twitter video. No affirmative source yet.

Don't you think it should take them at least a few days to determine a preliminary cause of the crash?

The Ukranian embassy in Tehran already have a statement on their website saying it's an engine malfunction and are ruling out a terrorist/rocket attack (reported by CNN and NYT).

Right, but the question is whether that's a reasonable conclusion for them to have made already.

The pilots of the plane would be in constant contact with the nearest airport during and right after take-off, especially when there are technical problems.

It's not hard to imagine the conversation would involve like:-

PILOT: One of the engines has failed catastrophically, we need to make an emergency landing, can you clear the runway back in Tehran or is there another airport we can go to?

But such a statement wouldn't rule out anything. Catastrophic engine failures can be caused by missiles.

It would take everyone a few days to determine the cause, especially the people spreading unverified informations such as 'it was shot down by a missile'

It wouldn't take very long for the relevant parties to know whether they accidentally shot a missile at a 737. For a mechanical issue, there would be much more uncertainty (although it's possible the pilot reported the issue to ATC).

And even then, "ATC, we have a catastrophic engine failure" from the pilots doesn't discount that the catastrophic engine failure was caused by a missile. The pilots don't magically get to know what caused the engine to blow up.

An independent investigation is impossible in the current environment. You either choose to believe Iran or not.

Pilot should be able to communicate even if engine is on fire (especially then). Transponder doesn't suddenly stop working if your engine erupts in flames.

Aviate, navigate, communicate.

They would have been rather occupied with the first two.

Good point. I concede. I'd still expect them to declare an emergency but it's possible that the event was so catastrophic they didn't find the time.

Its even fairly common, one guys is reading checklists and the other is, you know, flying the airplane.

To be fair, communication is different from ADS-B transmissions, which end abruptly at the flight's maximum speed and altitude: https://www.flightradar24.com/data/flights/ps752#23732569