160505-F-HG908-059
U.S. Air Force crew chiefs with the 1st Special Operations Aircraft Maintenance Squadron perform engine runs on an AC-130U Spooky gunship during Emerald Warrior at Hurlburt Field, Fla., May 6, 2016. Emerald Warrior is a U.S. Special Operations Command-sponsored mission rehearsal exercise during which joint special operations forces train to respond to real and emerging worldwide threats. (U.S. Air Force photo by Senior Airman Jeff Parkinson)