Guthrie 's tenure at BOAC was marred by a two fatal incidents ; the first , BOAC Flight 911 , occurred in March 1966 when a Boeing 707 experienced clear-air turbulence whilst overflying Mount Fuji in Japan . The crash resulted in the deaths of all 124 passengers and crew , the most deadly accident involving a British airline to date . Guthrie travelled to Japan to be involved in the investigation . The second fatal accident , BOAC Flight 712 , also involved a Boeing 707 . The aircraft suffered an un-contained engine failure during takeoff ; returning to Heathrow , the engine separated from the wing , causing the wing to catch fire . The aircraft cabin was destroyed by fire , and five people were killed
BOAC Flight 712
BOAC Flight 712
Giles Guthrie