A great film which keeps one's interest going until the very end. Well made with great acting. It is important to realise that the film is an aviation themed drama and NOT a documentary. The the film is set in the early 1950's, evidenced by the fact that it shows the De- Haviland Comet airliner, complete with BOAC livery. BOAC did not take delivery of the Comet until 1952 by which time the sound barrier, in realty, had been broken several times. Chuck Yeager, a US Air force pilot was the first man to break it in 1947. John Derry was the first British pilot to break it in 1948. Neither character, or their achievements, are mentioned in the film which is why l mention that the film should be seen as a fictional drama, losely based upon what was really happening in aviation at the time. A great film nevertheless which l have watched several times.