He went to the back of the plane with the ransom money and a parachute and jumped out over a wooded area at night. Did he survive the leap? Some think not. In 1980, this particular theory was given a real boost when a young boy found a rotting package of twenty-dollar bills ($5,800/£4,370) that matched the ransom money serial numbers.

In 2024, a pair of siblings claimed they had found the parachute used in the hijacking, in their mother's shed, and that 'Cooper' was their father. Richard McCoy Junior was a former helicopter pilot who served in Vietnam, and was among a number of suspects investigated by the FBI. After committing a similar crime in 1972, he was killed by an FBI agent following an escape from prison in 1974. The mystery remains officially unsolved.

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