Watch Channel 4 UK Documentaries online: Episode 22 The Mystery of the Nevada Triangle

In September 2007 Sir Richard Branson's friend, the record-breaking aviator Steve Fossett, disappeared on a pleasure flight. There were rumours that Fossett, who had made the first solo balloon flight around the world, was in Argentina or that he had faked his death. His loss sparked the biggest peacetime search and rescue operation in the history of the United States. Over the ensuing weeks, reports surfaced of hundreds - even thousands - of missing aircraft in a triangular area of the Sierra Nevada mountains that ranges from some of the highest peaks, to the lowest point - Death Valley - in the USA. Dating back to the early days of flight and World War II, the aircraft were lost in an area that also includes the top-secret 'Area 51' military air base, famous for unexplained UFO sightings. As reports of missing aircraft mounted, rumours grew of a new 'Bermuda Triangle': the so-called 'Nevada Triangle'. While the investigators faced challenges from wind, weather and terrain, many theories appeared to explain why so many planes had gone missing in the Nevada Triangle, from government conspiracy and alien intervention to unusual local atmospheric effects. This film reveals what really happened to Steve Fossett. But can it shed some light on the truth of the Nevada Triangle?

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