Kenneth Christiansen was a trained Army paratrooper who became a mechanic and then a flight attendant before his death in 1994. In 2003, Kenneth's brother, Lyle Christiansen, watched a documentary about the DB Cooper hijacking and became convinced that his late brother was behind the robbery. While Lyle made numerous attempts to convince FBI agents and filmmaker Nora Ephron that Kenneth — who was shorter, thinner, and lighter in complexion than eyewitness descriptions of Cooper — was behind the skyjacking, investigators shrugged off the theory.
Lyle then hired private detective Skipp Porteous to look into the case. Porteous went on to write a book hypothesizing that Kenneth could have been Cooper, but the FBI continues to reject the late flight attendant as a prime suspect, citing a lack of incriminating evidence and skydiving expertise.
