A Polygone employee uses a man-portable aircraft survivability trainer, or MAST, to simulate enemy fire for the aircrew of a C-130J Super Hercules aircraft assigned to the 37th Airlift Squadron, 86th Airlift Wing, Ramstein Air Base, Germany, during exercise Contested Forge on Grostenquin Air Base, France, Dec. 4, 2018. Contested Forge is an annual exercise that tests the 435th Contingency Response Group’s ability to build a forward operating base and conduct airfield operations in an austere environment, friendly or hostile. (U.S. Air Force photo by Staff Sgt. Timothy Moore)