November 24 marks 46 years since the world’s most infamous skyjacking that happened in our backyard.

On Thanksgiving Eve 1971, a man aboard a Portland to Seattle flight told the stewardess he had a bomb in his suitcase. He demanded $200,000 and four parachutes, which the FBI delivered when the plane landed at Sea-Tac Airport. The plane was refueled at his request and took off for Mexico.

When the plane was airborne again, headed south, the man, who became known as DB Cooper, jumped off the back staircase of the Boeing 727 into the frigid night sky.

In 2009, a band of amateur scientists were selected by the Seattle FBI to look for clues in the cold case.

The FBI closed the case in 2016 unsolved. The bureau was clearly frustrated by the lack of credible leads.

In January, the team’s analysis pointed to Cooper possibly being a Boeing employee.

The team continues to investigate, even though the FBI is unlikely to re-open the case.

Watch KING 5 News at 11 p.m. on Tuesday, for Chris Ingalls' look at rarely seen FBI files from the case. Watch on air, online and on the KING 5 app.