The world's stealthiest radar, the APQ-181 is a low probability of intercept, all-weather system that enables the B-2 Spirit stealth bomber to penetrate the most sophisticated air defenses.
The AN/APQ-181 radar system enables the unique combination of stealth, range, payload, and precision weapons delivery capabilities of the U.S. Air Force B-2 Spirit stealth bomber. The radar currently employs a passive, two-dimensionally scanned antenna, with a mode suite that provides detection and precision engagement of time-critical targets.
In 1991, the B-2 team (including Hughes, now Raytheon) was awarded the Collier Trophy, widely considered the most prestigious U.S. aviation award. The award was in recognition of the "design, development, production, and flight testing of the B-2 aircraft, which has contributed significantly to America's enduring leadership in aerospace and the country's future national security."
As part of the radar modernization program (RMP), Raytheon has designed, built and delivered an active array, based upon an advanced T/R module design offering improved performance and reliability. The RMP is currently in flight testing of the new antenna and will enter production in summer 2007, which will replace all the electronically scanned arrays currently in the fleet with the new active arrays. The new Active Electronically Scanned Array (AESA) provides the stepping stone to additional future radar enhancements.