[HTML1] Retired Staff Sgt. Travis Mills is a quadruple amputee who was critically injured by an IED while out on patrol during his third tour in Afghanistan. On Friday, he jumped out of a freakin’ airplane at 13,000 freakin’ feet while attached to a member of the Golden Knights parachute team. The Army documented the entire event in the skies above Homestead Air Reserve Base, Fla., and Mills is just fun to watch. When the plane is climbing to 6,000 feet, the cameraman inquires how Mills is feeling. Mills, with a huge grin on his face, says he’s ready to…