EGLIN AIR FORCE BASE, Fla. – John Crane, 36th Electronic Warfare Squadron B-1 defense systems engineer, monitors the B-1 Tail Warning Function test at the Central Control Facility at Eglin Air Force Base, Fla., Feb. 25. The TWF is a radar that faces the rear of B-1 to detect incoming missiles or aircraft. If detected the system can deploy defensive countermeasures. Crews from the 337th Test and Evaluation Squadron, Dyess Air Force Base, Texas, and fellow 53d Wing aircrew flew the B-1 mission at the Eglin range. (U.S. Air Force photo Capt. Carrie Kessler)