Senior Airman Frank Lainez, 316th Civil Engineer Squadron’s Heating, Ventilating, and Air Conditioning shop, shows Col. Steven M. Shepro, 316th Wing/Joint Base Andrews commander, how to check for holes in an air conditioning system on May 19. Colonel Shepro followed members of the HVAC shop as they fixed AC units on base as part of his last tactical level visit. (U.S. Air Force photo/ Senior Airman Melissa V. Brownstein)