How did the Nimrod AEW.3 solve radar coverage?

There was no room for a rotodome, so GEC turned to the Fore Aft Scanner System: one scanner housed in a bulbous radome in the nose and another in the tail. Eleven existing Nimrod airframes were to be converted by British Aerospace to house the GEC Marconi radars in a bulbous nose and tail.

The nose scanned left to right and then handed over to the tail, which scanned right to left, and together they were meant to produce 360-degree coverage. Getting the two to synchronise proved extremely difficult, and circular surveillance suffered as a result.

The Nimrod AEW3 project was plagued by cost overruns and problems with the GEC 4080M computer it used. The British Ministry of Defence eventually acknowledged that the cost of developing the radar system to the required performance level was prohibitive and that the chances of success were highly uncertain, and in December 1986 the project was cancelled.