The Sentry’s roles include air and sea surveillance, airborne command and control, weapons control and it can also operate as an extensive communications platform.
The RAF operates the E-3D Sentry aircraft in the airborne surveillance and command-and-control role. The aircraft are based at RAF Waddington, where they are operated by No 8Squadron as the UK’s contribution to the NATO Airborne Early Warning and Control Force. The E-3D also forms one arm of the UK Intelligence, Surveillance, Target Acquisition and Reconnaissance (ISTAR) triad of Sentinel R1, E-3D and Nimrod R1 aircraft. Whilst primarily procured as an airborne early warning aircraft, the E- 3D has been extensively employed in the Airborne Warning and Control System (AWACS) role. The E-3D Sentry, known to the RAF as the AEW1, is based on the commercial Boeing 707-320B aircraft, which has been extensively modified and updated to accommodate modern mission systems. Mission endurance is approximately 11 hours (over 5000nmls), although this can be extended by air - to- air refuelling. The E-3D is the only aircraft in the RAF’s inventory capable of air-to-air refuelling by both the American ‘flying-boom’ system and the RAF’s ‘probe-and-drogue’ method.
The normal crew complement of 18 comprises four flight-deck crew, three technicians and an 11-man mission crew. The mission crew comprises a tactical director (mission crew commander), a fighter allocator, three weapons controllers, a surveillance controller, two surveillance operators, a data-link manager, a communications operator and an electronic-support- measures operator. The Sentry’s roles include air and sea surveillance, airborne command and control, weapons control and it can also operate as an extensive communications platform.
The aircraft cruises at 30,000ft and 400kts and its Northrop Grumman AN/APY-2 high-performance, multimode lookdown radar, housed in the black radome, is able to separate airborne and maritime targets from ground and sea clutter. One E-3D flying at 30,000ft can scan at distances of over 300nmls; it can detect low-flying targets or maritime surface contacts within 215nmls and it can detect medium-level airborne targets at ranges in excess of 280nmls. The multi-mode radar provides lookdown surveillance to the radar horizon and an electronic vertical scan of the radar beam provides target elevation and beyond-the-horizon operation for long-range surveillance of medium and high-altitude aircraft. These attributes allow it to determine the location, altitude, course and speed of large numbers of airborne targets. The aircraft’s mission systems can separate, manage and display targets individually on situation displays within the aircraft, or it can transmit the information to ground-based and ship-based units using a wide variety of digital data links.