So, parts of AirAsia have been finally been recovered, and from the size of the debris field, it appears the plane probably hit the water mostly intact. Really no way to tell yet. My guess is the crew lost control of the plane. They were in a climbing turn at high altitude in very bad weather - 4 things that combined would be a recipe for a stall and total loss of control. When (and if) recovered, flight data recorder will show control inputs and aircraft trajectory. The CVR will likely reveal the last moments of horror for the doomed flight crew.