Staff Sgt. Justin Mceldowney trains Airman 1st Class Nathan Austin, both 28th Operations Support Squadron aircrew flight equipment technicians how to test night vision goggles on Ellsworth Air Force Base, S.D., Nov. 16, 2011. Pilots use night vision goggles to train for and conduct lowlight missions, an essential part of all combat operations. (U.S. Air Force photo by Airman Alystria Maurer/Released)