ELLSWORTH AIR FORCE BASE, S.D. - Airman 1st Class Robert Lyde, 28th Maintenance Squadron aerospace ground equipment technician, performs a phase two inspection on a hydraulic test stand, Sept. 7. Aerospace ground equipment technicians service, inspect, troubleshoot, repair and perform preventive maintenance on motor and engine-driven generator sets, air conditioners, hydraulic test stands, air compressors, bomb lifts, heaters and other similar support equipment. (U.S. Air Force photo/Staff Sgt. Marc I. Lane)