LANGLEY AIR FORCE BASE, Va. -- Staff Sgt. Gerald Redd, 71st Fighter Squadron dedicated crew chief, prepares the last F-15 for a new F-220 Pratt Whitney engine Jan. 11. The 71st FS Ironmen began receiving the engines in April and installed 40 engines within 10 months - two months ahead of schedule, according to Senior Master Sgt. Kerry Abner, 71st Aircraft Maintenance Unit noncommissioned officer in charge. (U.S. Air Force photo/Airman 1st Class Vernon Young)