AN/APQ-7

A B-29B of the 501st Bombardment Group takes off on a mission on 26 June 1945. The long horizontal bar running between the aircraft's landing gear is the antenna for the Eagle radar.

The AN/APQ-7, or Eagle, was a radar bombsight system developed by the US Army Air Force. Early studies started in late 1941 under the direction of Luis Alvarez at the MIT Radiation Laboratory, but full-scale development did not begin until April 1943. By this time US-built, higher frequency systems promising better performance over the existing British H2S radar were entering production. Eagle's even higher resolution was considered important to Air Force planners who preferred precision bombing but were failing to deliver it, and high hopes were put on the system's abilities to directly attack small targets like docks and bridges.

The war effort was already winding down when the first production units arrived in late 1944. A small number were fitted to B-17 Flying Fortress and B-24 Liberator aircraft intended for use in Europe, but none of these arrived in time to see action before the war ended. The system was first used operationally with the B-29 Superfortress in the Pacific Theater starting in May 1945. The addition of the APA-46 and 47 "Nosmo" synchronized a Norden bombsight with the APQ-7, and the entire assembly became known as the APQ-7A. The war ended shortly after this system was introduced, and Eagle saw little real world use. Post-war efforts focused on the K-system, as Eagle's unique antenna design made it difficult to use with higher speed jet powered bombers.