During a severe thunderstorm over Washington state, a hijacker calling himself Dan Cooper (aka D. B. Cooper) parachutes from a Northwest Orient Airlines plane with $200,000 in ransom money. He has never been found.

Washington, officially the State of Washington, is a state in the Pacific Northwest region of the United States. It is often referred to as Washington State to distinguish it from the national capital, both named after George Washington. Washington borders the Pacific Ocean to the west, Oregon to the south, Idaho to the east, and shares an international border with the Canadian province of British Columbia to the north. Olympia is the state capital, and the most populous city is Seattle.

Aircraft hijacking is the unlawful seizure of an aircraft by an individual or a group. Dating from the earliest of hijackings, most cases involve the pilot being forced to fly according to the hijacker's demands. There have also been incidents where the hijackers have overpowered the flight crew, made unauthorized entry into the cockpit and flown them into buildings—most notably in the September 11 attacks—and in some cases, planes have been hijacked by the official pilot or co-pilot, such as with Ethiopian Airlines Flight 702.

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 and four parachutes upon landing in Seattle. After releasing the passengers in Seattle, Cooper directed the flight crew to refuel the aircraft and begin a second flight to Mexico City, with a refueling stop in Reno, Nevada. Approximately thirty minutes after taking off from Seattle, Cooper opened the aircraft's aft door, deployed the air stair, and parachuted into the night over southwestern Washington. Cooper's identity, whereabouts, and fate have never been conclusively determined.