Namibian investigators concluded that the Novemner 2013 accident of a LAM Mozambique Airlines ERJ-190 was caused by intentional actions by the captain.
The report states: “The inputs to the auto flight systems by the person believed to be the captain, who remained alone on the flight deck when the person believed to be the co-pilot requested to go to the lavatory, caused the aircraft to deviate from cruise flight to a sustained controlled decent and subsequent collision with the terrain.”
The flight was still in radio contact with Gaborone Area Control and the Namibian radar data playback revealed that at position EXEDU, which is a mandatory point in the Gaborone Flight Information Region, the aircraft suddenly descended from the normal cruising level of 38000 feet.
The altitude was manually adjusted three times, from 38000 feet to a final 592 feet, which is below ground elevation. The report also states that auto throttle was manually re-engaged and the throttle level was automatically restarted and set to idle.
The airspeed was then manually selected several times and it remained at the maximum operating speed until the end of the recording. During all these actions there was banging on the cockpit door.
The investigators recommended to the Mozambican Civil Aviation Authority that measures should be put in place to ensure that the procedure of two people in the flight deck is adhered to at all times.
It has also been recommended to the International Civil Aviation Organisation (ICAO) that a working group should be established to look into the operation and the threat management emanating from both sides of the cockpit door and that recommendation should be made to avert the locking out of the cockpit of authorised crew members.
It was further recommended that visual recording devices should be installed inside and outside the cockpit that provide information on who was in the cabin and who was controlling the plane at the time of an accident. It was also recommended that the research with regard to the implementation of aircraft tracking and localisation should be sped up.