The EgyptAir A320 Airbus designated Flight MS804 left Paris at 21.09 GMT. It was due to land in Cairo at 01.15 GMT. Twenty minutes prior to landing the plane made a series of abrupt course changes and disappeared from the Greek air traffic control radar that was tracking it.
General speculation suggests either a bomb, or catastrophic failure, caused the aircraft to crash into the Mediterranean Sea.
While the latter remains a remote possibility, the chances of it being a bomb seem equally unlikely. U.S. satellite sources state the aircraft could not have blown up, as the blast would have registered on their equipment. Also, historically, most explosive devices placed on airplanes have been timed to explode within an hour or so of take-off. Waiting until twenty minutes prior to landing could have caused the bomb not to explode until the aircraft was on the ground, had it arrived early at Cairo – a distinct possibility on a four hour flight.
Catastrophic failure is virtually unknown on an aircraft that has almost completed its flight. Take-off and landings are the times of most airframe stress, not at 37,000 feet and with the engines throttled back to cruising speed.
The pilot made contact with Greek ATC at 23.24 GMT, approximately 2 hours and 15 minutes into the flight. At 00.27 GMT Greek controllers failed to make contact with the plane, either on normal or emergency frequencies. Yet the plane was still being tracked by radar and appeared on a normal flight-path for a full 2 minutes and 40 seconds before it disappeared.
Egyptian radar lost track of the aircraft 20 seconds later, at 00.30 GMT.
According to the Greeks, the plane made an abrupt turn to the left before plummeting to 15,000 feet. At 10,000 feet they lose sight of it. ATC radar is designed to track aircraft at high altitudes, so it may be the aircraft dropped below radar level very quickly, but didn’t necessarily crash into the sea.
Of course, this is all speculation, but where is the wreckage? This is the Mediterranean Sea, not the wilds of the Southern Indian Ocean where MH370 supposedly crashed. It’s barely a mile deep in the Levantine Basin, where MS804 is alleged to have gone down. An aircraft plummeting from 37,000 feet into the ocean would break apart on impact, scattering debris over a wide area. Either the search aircraft and vessels aren’t proving very observant, or the aircraft isn’t where everyone says it is.
There is another option: a simulated crash. The aircraft is forced into a steep, spiralling, dive down to 10,000 feet, or probably less, to give the impression of a crash, before levelling out and ‘wave-hugging’ until reaching the coast of a designated country. Tunisia, Libya, Lebanon, Syria, all border the Mediterranean in that area.
Even as this is being written debris of Flight MS804 could be pulled from the depths, and the mystery, at least partially, solved. Maybe the aircraft did crash somewhere in the Levantine Basin, but in an area of many local fishing communities, heavily trafficked, why did no-one see or hear anything as this aircraft came down? And why is the wreckage proving so difficult to locate?
A fatal crash, or a very clever hijacking? Only time will solve that mystery.
 “MH370 – Flight To Armageddon” Sparrow Chat, January 29th 2015
 “EgyptAir flight MS804: What we know” BBC, May 19th 2016
ADDENDUM: Sadly, it now looks like MS804 did indeed crash into the Mediterranean, with the loss of all on board. Reports are coming in of debris: seats, luggage, even body parts being found.
The remaining question is what caused this crash. Some experts are saying that the erratic course changes the plane made prior to being lost from radar, point to interference on the flight deck, rather than an explosive device:
Mike Vivian, former head of operations at the UK’s Civil Aviation Authority, told the BBC that the plane’s sharp manoeuvres before disappearing from radar were more likely to be caused by human interference than a bomb.
“It looks highly unlikely that this was consistent with some sort of explosive device,” he said.
“One’s inclined to go towards the theory that there had been some interference in the aircraft and on the flight deck, with the control of the aircraft.”
If that’s the case, what sort of interference, and by whom? If, as one would anticipate, the cockpit door was locked and reinforced, then how could anyone gain access? Or, was the ‘interference’ by the pilot, or co-pilot?
There’s still a slight possibility that catastrophic failure, perhaps somewhere within the wing structure, may have caused the erratic behavior of the aircraft prior to it plunging to its doom in the ocean.
It may be a long time before these answers are known.