he is a man who jumped out of an airplane.
D.B. Cooper is a man who hiijacked an aeroplane on November 24th 1971 in the U.S.A. and held them for $200,000 ransom. He later paruchuted out of the plane...
D. B. Cooper (boarded the plane as Dan Cooper, but a media misconception labeled him as "D.B. Cooper, which stuck) was a man who hijacked a Boeing 727 aircraft in the United States on November 24,...
No one knows if Dan cooper is a real or made up name. I think it is a made up name because i don't think he would take the chance of being traced. So to answer your question no one really knows.
Two possibilities: Only 'Dan Cooper' knew, or only the FBI knows. If the FBI recovered the briefcase with the 'bomb', they would likely keep this information secret to aid in investigating suspects,...