Cone of Silence (also known as Trouble in the Sky in the United States) is a 1960 British drama film directed by Charles Frend and starring Michael Craig, Peter Cushing, George Sanders and Bernard Lee. The film is based upon the novel of that name by David Beaty, which is loosely based on a 1952 plane crash in Rome and subsequent investigations into the structural integrity of the de Havilland Comet airliner.The title refers to a technical term used in the low-frequency radio range. An identification of a range's cone of silence is shown early in the film.