Unexplained Mystery of Skyjacker http://theunexplainedmysteries.com/fbi-skyjacke... It's dirty and it's old, but a piece of cloth found in a Washington field might hold the key to solving one of the FBI's most enduring mysteriesOn Nov. 24, 1971, an unassuming man wearing a business suit and appearing to be in his mid-40s allegedly hijacked and threatened to blow up a Northwest Orient Airlines plane traveling from Portland, Ore., to Seattle if he did not get four parachutes and a $200,000 ransom.