In the environment of reduced defense spending, radar systems aboard fielded, high performance air-superiority fighters need to be more affordable and reliable while providing equivalent or better performance. The mechanical antenna gimbal and the tube transmitter have historically been the most unreliable parts of the radar system. Conventional two-dimensional electronically scanned antenna (2D ESA) technology can significantly improve antenna subsystem reliability but does so with a higher recurring cost to the user. The Hughes Aircraft Company has been involved in the development of new 2D ESA concepts that address the drawbacks of conventional 2D ESAs. These concepts are being developed as part of the United States Air Force, Wright Laboratories Radar Branch (WL/AAMR) sponsored, Radar System and Aperture Technology (RSAT) program.