Confesso, que quando vi o release inicial pensei o mesmo... Suicidio. Mas, citação do AVH:
Also, about this time, the FDR data indicated that some small vertical accelerations consistent with the airplane entering turbulence. Shortly after, when the airplane’s indicated airspeed was steady about 230 knots, the engines increased to maximum thrust, and the airplane pitch increased to about 4° nose up. The airplane then pitched nose down over the next 18 seconds to about 49° in response to nose-down elevator deflection. (Editorial Note: the sentence originally read: "and then rapidly pitched nose down to about 49° in response to column input." and was later edited by the NTSB). The stall warning (stick shaker) did not activate.
a alteração dessa frase muda muito.
Existem em curso inspecções e modificações na zona dos elevators do 767, como a AD 2013-25-03. Pode ter havido falha mecanica mesmo.