What happened
The aircraft, identified as HP.42 and bearing the name 'Hannibal', disappeared while operating over the Gulf of Oman. The plane crashed into the sea under circumstances that remain unknown. Search and rescue teams conducted operations for several days but failed to locate any trace of the aircraft or its occupants. Consequently, the search efforts were suspended without success.
The flight carried a crew of four individuals, including the pilot, copilot, radio operator, and steward, along with four passengers. All eight people on board were lost in the incident. No wreckage or debris was recovered from the water during the investigation period.
Findings
Investigations by the UK Air Ministry evaluated several potential causes for the disappearance. They deemed it improbable that the crash resulted from sabotage, hostile action, or an inflight fire. While complete fuel exhaustion was also considered unlikely, the possibility of gasoline starvation due to improper activation of controls could not be entirely ruled out.
Other hypotheses included a bird strike that damaged a propeller, potentially leading to engine mounting failure or the loss of an entire wing. Structural failure was another significant consideration, particularly given the age of the aircraft and known vibration issues associated with this type. Multiple power plant malfunctions were also cited as possible precursors to structural collapse.
Following the incident, the British government announced that the HP.42 would no longer be used for passenger operations. Additionally, recommendations were made to ensure that commercial aircraft undertaking long over-water flights were equipped with personal and group life-saving gear, a standard that subsequently became industry-wide practice.