The established facts are that the aircraft, a Boeing 737-800, landed without the crew deploying flaps - which made the touchdown much faster than usual - and without the pilots lowering the undercarriage, which means the crew could not use braking to slow the aircraft down on the runway.

As a result, the aircraft belly-landed and overran the far end of the runway still travelling very fast, and it collided with an obstruction less than 200m beyond it and directly in line with the runway. 

Before that collision took place, the aircraft was structurally sound and there was no sign of fire. 

At the point of collision, the aircraft’s fuselage buckled, broke up and instantly exploded into fire, the wreckage coming to rest just beyond the obstruction.

Before this final landing, there is a lot that has yet to be understood, particularly why the pilots did not deploy the flaps or the landing gear. 

The crew first attempted a landing on the same runway from the opposite end, but abandoned that approach for some reason and climbed once again before returning for the final attempt.

The pilots put out a Mayday call before committing to the fatal approach, but did not describe the problems they faced – possibly because they were dealing with a major problem and did not have time to report. 

Air traffic control warned the crew of birdstrike danger – flocks of birds can damage an aircraft and its engines badly, and there is some reason to believe that such an event may have damaged - or even stopped - the right engine of this aircraft. 

Impact damage can cause hydraulic systems failure, and if this had happened it could explain why the flaps and gear had not been deployed, because they are hydraulically powered.

The deadly obstruction with which the aircraft collided appears to be the anchorage for an array of aerials, possible for the Instrument Landing System which guides crews to the runway in poor visibility. 

But such aerials are normally designed to collapse if an aircraft hits them, causing minimal damage.

David Learmount is former RAF pilot, aviation expert and flight analyst.