**Summary:**
In 1971, a man, later known as DB Cooper, hijacked a commercial flight in the United States. He handed a note to a flight attendant, claiming to have a bomb and demanding $200,000 and parachutes. After receiving the ransom, he parachuted from the plane, disappearing without a trace. Despite extensive investigations, the FBI never identified or apprehended Cooper. Various suspects emerged, but none were proven to be the infamous hijacker. The case remains one of the most mysterious unsolved crimes, inspiring numerous stories and adaptations in popular culture.
Here are the key facts extracted from the text:
1. In 1971, on November 24th, a commercial flight in the United States was hijacked.
2. The hijacker handed a note to a flight attendant, claiming to have a bomb in his suitcase.
3. The hijacker demanded $200,000 in cash and four parachutes.
4. The flight circled in the air for an extended time while the money and parachutes were prepared.
5. After receiving the ransom and parachutes, the hijacker jumped from the plane.
6. The hijacker was never found or identified.
7. The hijacker used the name "DB Cooper," although this was likely an alias.
8. The FBI investigated numerous suspects but could not conclusively identify the hijacker.
9. Some theories suggested a connection to the CIA, but no concrete evidence was found.
10. The case remains one of the most mysterious unsolved robberies in history.