The accident investigation board says in today´s press release that flight data recorder readout, as well as interviews with the pilots, have confirmed that for some as yet unknown reason, when the pilots were attempting to recover from the tail slide, the aircraft´s control systems switched over to mechanical backup steering and the ensuing straight-down dive proved impossible to control. The pilots were forced to eject when airspeed approached critical values.
Puolustusvoimat - Frsvarsmakten - The Finnish Defence Forces (in Finnish only)