My wife used to be a flight attendant so we're sort of more touched by it. We have a daily dosage of phone calls and fb messages with people who knew some of the victims. From what I know so far the pilot and copilot were very experienced and people think that most likely it's not a technical failure. The plane made transit stops in Eritrea and Tunisia before Paris so it could be that something was planted on the plane. But on the other hand one would expect the french authorities to be extremely thorough after the Paris attacks.
This accident Tamer is very strange in that whatever happened, happened quite abruptly. Looking at the timeframe there is about a 2min gap between the last attempted call from ATC (air traffic control) and radar data showing the aircraft in a very steep dive (certainly uncontrolled). Last coms with the pilots were at 01:48 and at 02:27 controllers attempted to call the aircraft to transfer frequency to Cairo control as it was approaching the boundary to Cairo airspace. At 02:27 there was no reply from the aircraft which was still at 37,000ft. Two minutes later at 02:29 radar shows the aircraft in a steep dive which became a spiraling dive at around 20,000ft and at around 9000 ft the aircraft was lost from radar.
Now I can tell you since I flew the Airbus A320 from 1991 till 2000 that even if the pilots want to purposely put it in a 12,000 ft/min dive it's not possible as the flight control computer protections will kick in and override the pilots inputs. The A320 is a fly-by-wire aircraft which means that the flight control computers have a certain flight envelope they permit the pilots to operate within. Of course these computers can be switch off manually but that is something which isn't permitted in flight and no Airbus fly-by-wire pilot in his right mind would ever do.
There seems to be speculation of a terrorist act however in my mind that's highly unlikely because it just doesn't make
sense. If a bomb was onboard why wait to detonate it over the Mediterranean Sea 25min before landing when the aircraft flew from Paris (over the city), Switzerland, Italy and Greece. I'm not ruling out that possibility but in my mind it's highly unlikely.
The fact that at 02:27 the aircraft was still at 37,000ft and there was no reply from ATC repeated calls and then plummeted later at 02:29 into an uncontrolled dive suggest to me a serious technical problem.
The A320, despite "experts" opinions in the media can fly with no electrical power. There are backup systems in the event of a total electrical failure and A320 pilots are trained in the simulators for that. I can tell you that it's not easy to fly in Emergency Electrical situation but it's certainly very controllable. On the other hand the A320 cannot fly with the loss of total hydraulics. The Aircraft has 3 hydraulic systems and the probability of all three failing is close to zero due to the architecture of the system design.
If indeed it was a serious technical failure occurred it certainly will be known once the DFDR's (digital flight data recorders known as the black boxes) are recovered. If it was a terrorist act debris will both indicate explosive damage from in to out as well as explosive residue.
Whatever the case may be it doesn't change the tragic fact that 66 souls were lost in this accident.