Avro York G-AHFA was on a trooping flight from Stansted to Jamaica when it took off from Lajes AFB, Azores at 23:25 for a flight across the Atlantic Ocean to Gander. Weather conditions were considered favourable for the flight. The radio operator transmitted approximately hourly position reports. Last radio contact was at 05:31 when an SOS-call was received by Gander. Last position was Lat 46deg 15’N Long 46deg 31’W. An area of 68000 square miles was searched but no trace of the aircraft was found. On 3 February 1953 United States Coast Guard cutter Campbell reported several large oil patches and dye markers about 120 miles south-west of the last reported position of the aircraft. There was no mention of this oil patch in the final investigation report, so it may have been determined not to have originated from the missing aircraft. During the investigation it was noted that the flight was supposed to have a minimum of 9 hours rest after 9 hours of flying. Arriving at Lajes, the crew had been on duty at least 9 hours. The turn-around took just over 4 hours during which time it is unlikely that the crew had any time for recuperative rest. At the time of the emergency the crew had been on duty for over 19 hours. The investigators recommended that an in-depth study be undertaken with regards to crew fatigue. Cause: Unascertainable.