AN/APY-1/2

The AN/APY-1 is an S-band (IEEE designation) or E-band (NATO designation) primary airborne radar system developed by Westinghouse (now Northrop Grumman) for the E-3A Airborne Warning and Control System (AWACS) aircraft. Its surveillance antenna is mounted back-to-back with an L-band identification-friend-or-foe (IFF) antenna within a 30-ft (9.14 m) diameter rotodome, which rotates at 6 revolutions per minute and is supported by two struts on the rear fuselage. The AN/APY-2 is a variant that adds maritime surveillance capabilities. Development began in January 1973 and concluded in September 1994, with subsequent improvements under the Radar System Improvement Program (RSIP) enhancing its performance against small airborne targets, electronic counter-countermeasures (ECCM) capability, reliability (with a mean time between critical failures of 4,300 hours), and maintainability (with a mean time to repair of 36 minutes), allowing detection and identification of non-cooperative targets out to an instrumented range of 216 nautical miles (400 km) and an upgraded range of 300 nautical miles (556 km).

radartutorial.eu: https://www.radartutorial.eu/19.kartei/08.airborne/karte094.en.html