Second unit director John Jordan refused to wear a harness during a bomber scene. While giving a hand signal to another airplane from the tail gunner position in the camera plane, he lost his grip and fell 4,000 feet into the Pacific Ocean to his death.
https://en.wikipedia.org/wiki/Catch-22_(film)
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https://imdb.com/title/tt0065528/trivia/?item=tr0593143&ref_=ext_shr_lnk
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