The hijacker, claiming to have a bomb, demanded $200,000 and four parachutes.
After landing in Seattle and releasing the passengers, he ordered the crew to refuel for a flight to Mexico City, with a stop in Reno.
About 30 minutes after takeoff, he parachuted from the plane over southwestern Washington and was never found or identified.
Detailed article about the case: https://historicflix.com/d-b-cooper-the-mystery-hijacker-of-flight-305/
Funfact: the hijacker used always the name „Dan Cooper“ never „D. B. Cooper“, the middle initial was either accidentally or intentionally created by the media.