A woman stand in front of an AirAsia check-in machine at Soekarno Hatta airport in Jakarta, January 21, 2015. [Photo/Agencies]

JAKARTA - The AirAsia passenger jet that crashed into the sea last month killing all 162 people was in sound condition and all crew members were properly certified, Indonesia's National Transportation Safety Committee said on Thursday.

Mardjono Siswosuwarno, head investigator for the National Transportation Safety Committee, told reporters the flight data recorder provided a "pretty clear picture" of what happened in the last moments of AirAsia Flight QZ8501.

He added that the first officer was flying the plane at the time of the accident, which killed all 162 people on board.