The DC-6 aircraft was on a scheduled flight from Saigon to Paris, France and had left Karachi for Cairo on 19 February at 17:15 UTC. The captain, a company DC-6B check pilot, occupied the right-hand seat during the flight leg between Karachi and Cairo, and the co-pilot, the left-hand seat. He was being checked on this flight as a DC-6B trainee-captain. The flight was routine until 02:30 (20 February) when the aircraft reported to Cairo Air Traffic Control that it had passed Suez (60 miles east of Cairo) at 02:24 at a flight level of 8500 feet, flying VFR and was descending. At 02:40 it reported the Cairo aerodrome in sight and being 15 miles out, was granted an authorization for a VFR approach and at the same time was given the QFE and QNH, 29.42 and 29.73 respectively. Contact was established with Cairo approach and the aircraft requested and received landing instructions and was asked to call down wind. When the crew reported the airport in sight, at an altitude of 4500 feet, both crew members thought they were going to overshoot so they lowered the undercarriage and the flaps to increase the rate of descent while maintaining the same speed. The airplane descended to an altitude of 2000 feet, which is 1500 feet below the minimum safe flight altitude for the sector. Descent was continued until the aircraft struck the ground in a nose down attitude. The starboard wing ruptured following the severe shocks sustained by the landing gear, engines and propellers. A fire erupted. PROBABLE CAUSE: “The accident was due to the failure of the pilot-in-command to monitor the co-pilot during a direct approach procedure and the reliance of the latter on his instruments exclusively to fix his position relative to the runway at an altitude below the minimum safe altitude. The factor of crew member fatigue can not be ruled out.”