On 8 April 1954 , Comet G-ALYY ( " Yoke Yoke " ) , on charter to South African Airways , was on a leg from Rome to Cairo ( of a longer route , SA Flight 201 from London to Johannesburg ) , when it crashed in the Mediterranean near Naples with the loss of all 21 passengers and crew on board . The Comet fleet was immediately grounded once again and a large investigation board was formed under the direction of the Royal Aircraft Establishment ( RAE ) . Prime Minister Winston Churchill tasked the Royal Navy with helping to locate and retrieve the wreckage so that the cause of the accident could be determined . The Comet 's Certificate of Airworthiness was revoked and Comet 1 line production was suspended at the Hatfield factory while the BOAC fleet was permanently grounded , cocooned and stored
SA Flight 201
South African Airways Flight 201
De Havilland Comet