Airman 1st Class Eric Campbell, 4th Aircraft Maintenance Unit aerospace propulsion journeyman, works on an AC-130U Spooky Gunship at Hurlburt Field, Fla., May 16, 2014. The 4th AMU helps generate approximately 1000 training missions annually for the Spooky. (U.S. Air Force photo/Senior Airman Christopher Callaway)