U.S. Air Force Senior Airman James Mullen and Airman 1st Class Viviana Lara, from the New Jersey Air National Guard's 177th Fighter Wing in Egg Harbor Township, perform maintenance on an F-16 Fighting Falcon on Jan. 9, 2015. The Airmen worked through bitter cold winter temperatures while participating in an aircraft generation exercise. (U.S. Air Force photo by Airman 1st Class Amber Powell/Released)