Senior Airmen Derand Javier and Chris Moore test the head spacing of a .50-caliber machine gun.
U.S. Air Force Senior Airmen Derand Javier and Chris Moore, both weapons specialists with the 64th Aircraft Maintenance Unit, test the head spacing of a .50-caliber machine gun on an HH-60G Pave Hawk helicopter at Balad Air Base, Iraq, on March 25, 2008. Both airmen are deployed from Moody Air Force Base, Ga.