Sweden's S100B Argus AWACS takes off from Waddington - The S100B Argus Airborne Early Warning and Control Aircraft entered service with the Swedish Air Force in 1997. The S100B is a Saab 340B aircraft, built by Saab Aircraft, with an Erieye mission radar from Ericsson Microwave Systems. A 9m-long, 900kg antenna unit is mounted on the upper spine of the fuselage. Six S100B Argus aircraft were produced for the Swedish Air Force, four of which are permanently equipped with early warning radar and two fitted for transport missions during peacetime.

In the mid-1970s the Nimrod's duties were expanded to include Airborne Early Warning and Control (AEW) — as a replacement for the Lancaster-derived, piston-engined Shackleton which was still in service in that role. The aircraft were modified by British Aerospace at the former Avro plant at Woodford, Greater Manchester to house the GEC Marconi radars in a bulbous nose and tail. From the start of the first flight trials in 1982 the Nimrod AEW3 project was plagued by cost over-runs and problems with the GEC 4080M computer used for the Mission System Avionics (MSA). http://www.spyflight.co.uk/Nim%20aew.htm

AWACS vs AEW Nimrod