Pictures from the FBI Wanted poster for D.B. Cooper

On the night before Thanksgiving, November 24, 1971, a passenger by the name of Dan Cooper boarded a plane in Portland, Oregon, bound for Seattle. Clad in a suit and raincoat, wearing dark glasses and carrying a briefcase, he sat silently in the back of the plane.

After calmly lighting a cigarette, he ordered a whiskey from the stewardess and then handed her a note. It read, “I HAVE A BOMB IN MY BRIEFCASE. I WILL USE IT IF NECESSARY. I WANT YOU TO SIT NEXT TO ME. YOU ARE BEING HIJACKED.”

He demanded $200,000 and four parachutes delivered to him in Seattle. When the plane landed, he released all the passengers, except for the pilot, co-pilot, and stewardess. Once the money was delivered in the middle of the brightly-lit tarmac, Cooper demanded the pilot take off for Mexico, flying at an altitude of 10,000 feet.

Shortly after takeoff, over the mountains northwest of Portland, the six-foot-tall Cooper strapped on a parachute and jumped. He was never heard from again. Did he survive? In 1980, roughly $6,000 was found of the money in bundles on a beach, but no signs of a body. The case remains open and is the only unsolved crime in US aviation history.
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On July 12, 2016, the FBI announced it was closing its investigation, concluding that it was unlikely that any new information would lead to solving the 45-year-old mystery.