Staff Sgt. Bryan Cummings, 11th Civil Engineer Squadron HVAC craftsman, teaches other airmen while repairing an air conditioning unit at the Child Development Center Three on Joint Base Andrews, Md., July 13, 2016. The HVAC flight cares for approximately 2,400 air conditioning units throughout JBA. (U.S. Air Force photo by Senior Airman Mariah Haddenham)