Cockpit voice recorder transcripts from the last minutes of the flight before impact with Mount Erebus indicated that the flight crew believed they were flying over McMurdo Sound, well to the west of Mount Erebus and with the Ross Ice Shelf visible on the horizon, when in reality they were flying directly toward the mountain. Despite most of the crew being engaged in identifying visual landmarks at the time, they never perceived the mountain directly in front of them. Approximately six minutes after completing a descent in Visual Meteorological Conditions, Flight 901 collided with the mountain at an altitude of approximately , on the lower slopes of the tall mountain. Passenger photographs taken seconds before the collision removed all doubt of a flying in cloud theory, showing perfectly clear visibility well beneath the cloud base, with landmarks to the left and to the right of the aircraft visible.