D. B. Cooper

D. B. Cooper, also known as Dan Cooper, was an unidentified man who hijacked Northwest Orient Airlines Flight 305, a Boeing 727 aircraft, in United States airspace on November 24, 1971. During the flight from Portland, Oregon, to Seattle, Washington, Cooper told a flight attendant he had a bomb, and demanded $200,000 in ransom (equivalent to $1,600,000 in 2024) and four parachutes upon landing in Seattle. After releasing the passengers in Seattle, Cooper instructed the flight crew to refuel the aircraft and begin a second flight to Mexico City, with a refueling stop in Reno, Nevada. About thirty minutes after taking off from Seattle, Cooper opened the aircraft's aft door, deployed the staircase, and parachuted into the night over southwestern Washington. Cooper's true identity and whereabouts have never been determined conclusively.

In 1980, a small portion of the ransom money was found along the riverbanks of the Columbia River near Vancouver, Washington. The discovery of the money renewed public interest in the mystery but yielded no additional information about Cooper's identity or fate, and the remaining money was never recovered. For forty-five years after the hijacking, the Federal Bureau of Investigation (FBI) maintained an active investigation and built an extensive case file but ultimately did not reach any definitive conclusions. The crime remains the only documented unsolved case of air piracy in the history of commercial aviation. The FBI speculates Cooper did not survive his jump for several reasons: the inclement weather, Cooper's lack of proper skydiving equipment, the forested terrain into which he jumped, his lack of detailed knowledge of his landing area and the disappearance of the remaining ransom money, suggesting it was never spent. In July 2016, the FBI officially suspended active investigation of the case, although reporters, enthusiasts, professional investigators and amateur sleuths continue to pursue numerous theories for Cooper's identity, success and fate.

Cooper's hijacking — and several imitators during the next year — immediately prompted major upgrades to security measures for airports and commercial aviation. Metal detectors were installed at airports, baggage inspection became mandatory and passengers who paid cash for tickets on the day of departure were selected for additional scrutiny. Boeing 727s were retrofitted with eponymous "Cooper vanes", designed to prevent the aft staircase from being lowered in-flight. By 1973, aircraft hijacking incidents had decreased, as the new security measures dissuaded would-be hijackers whose only motive was money.