The information that is being released about the flight of this aircraft just before its impact with the ground bear a remarkable similarity to what happened with Indonesia Air Asia Flight 8501, which plunged into the Java Sea on December 28, 2014.
The Russian Metrojet aircraft went through some very severe and dramatic excursions in airspeed and altitude, and this is now an established fact. Its climb and descent rate was excessive, and its airspeed went from below stall speed to near Vne. My understanding is that there were at least three major climb and dive excursions.
These excursions could not have happened if the aircraft was simply blown apart by an explosive.
What is much more likely is that the flight control computers somehow became disconnected from the flight controls and the pilot had to take over control manually. In other words, the aircraft was then in the Airbus "Direct" flight control law.
Flying an A321 manually at 30,000 feet altitude would not be easy. Many airlines do not give pilots any simulator time in such a flight regime. Being able to take over control manually is something similar to trying to play a musical instrument. It takes time and practice. To do this training in a simulator would be costly.
The Air Asia pilot took over the flight controls using manual (Direct) control, and he failed. it might also be noted that a similar occurrence happened with the Air France 447 disaster.
I expect that the FDR will establish that the pilot actually over-controlled the aircraft and in the process actually tore the elevator and maybe the elevators from the tail. Or possibly that the entire tail empennage separated at altitude.
The Egyptian Government has custody of the CVR and FDR. I suspect that we won't have information about their analysis for several weeks.