At the time of the accident , the investigation into the crash of BOAC Flight 781 was still in progress , but suspicion of the cause of the crash had fallen on the possibility of an engine turbine failure . During the previous grounding of all Comets , modifications had been made to the aircraft , including '' Yoke Yoke '' , that seemed to eliminate this possibility
BOAC Flight 781
BOAC Flight 781
South African Airways Flight 201