An impromptu yoga routine wasn't enough to calm an irate passenger aboard a United Airlines flight that had to be turned around mid-flight on Saturday. Hyongtae Pae, 72, of South Korea was headed home from Hawaii, where he'd celebrated his 40th wedding anniversary, when he felt the urge to do some yoga and meditate, and headed to the back of the plane. When his wife and flight attendants told him to return to his seat, Pae pushed his wife, tried to head-butt and bite Marines on board, threatened to kill passengers, and yelled that there was no god, a prosecutor tells the AP. Pae, now held in Hawaii, told the FBI he hadn't slept in 11 days. He urinated on himself while in detention and was on suicide watch. (More United Airlines stories.)