An Embraer ERJ-190 aircraft crashed in Namibia during a flight from Maputo to Luanda, likely due to a deliberate act by the captain. The aircraft was destroyed, and all 27 passengers and six crew members were killed. The flight departed Maputo at 11:26 UTC and was scheduled to land at Luanda at 14:10 UTC. The airplane proceeded over Botswana at FL380 and was in contact with Gaborone ACC. At the EXEDU waypoint, approximately 13:09 UTC, the aircraft commenced a sudden descent, which continued until the airplane impacted the ground at 11:16:26 UTC. Minutes before the crash, the co-pilot left the cockpit for the lavatory. The captain then manually changed the altitude preselector from 38,000 feet to an altitude of 4,288 feet, then to 1,888 feet, and finally to 592 feet. The auto throttle was manually reengaged and throttle lever then automatically retarded and set to idle. The airspeed was manually selected several times until the end of the recording, which remained close to the Vmo (maximum operating limit speed). During the descent, the captain used the speed brake handle to activate the spoilers. On the cockpit voice recorder sounds were heard of someone pounding on the cockpit door. It was discovered that the captain went through numerous life experiences ranging from uncompleted divorce process, the suspected suicide of his son on November 21, 2012, and a recent heart surgery of his youngest daughter. Probable Cause: 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 depart from cruise flight to a sustained controlled descent and subsequent collision with the terrain. Contributing factors: The non-compliance to company procedures that resulted in a sole crew member occupying the flight compartment.An Embraer ERJ-190 aircraft crashed in Namibia during a flight from Maputo to Luanda, likely due to a deliberate act by the captain. The aircraft was destroyed, and all 27 passengers and six crew members were killed. The flight departed Maputo at 11:26 UTC and was scheduled to land at Luanda at 14:10 UTC. The airplane proceeded over Botswana at FL380 and was in contact with Gaborone ACC. At the EXEDU waypoint, approximately 13:09 UTC, the aircraft commenced a sudden descent, which continued until the airplane impacted the ground at 11:16:26 UTC. Minutes before the crash, the co-pilot left the cockpit for the lavatory. The captain then manually changed the altitude preselector from 38,000 feet to an altitude of 4,288 feet, then to 1,888 feet, and finally to 592 feet. The auto throttle was manually reengaged and throttle lever then automatically retarded and set to idle. The airspeed was manually selected several times until the end of the recording, which remained close to the Vmo (maximum operating limit speed). During the descent, the captain used the speed brake handle to activate the spoilers. On the cockpit voice recorder sounds were heard of someone pounding on the cockpit door. It was discovered that the captain went through numerous life experiences ranging from uncompleted divorce process, the suspected suicide of his son on November 21, 2012, and a recent heart surgery of his youngest daughter. Probable Cause: 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 depart from cruise flight to a sustained controlled descent and subsequent collision with the terrain. Contributing factors: The non-compliance to company procedures that resulted in a sole crew member occupying the flight compartment.