In 1963, the USAF asked for proposals for an Airborne Warning and Control System (AWACS) to replace its EC-121 Warning Stars, which had served in the airborne early warning role for over a decade.
En 1963 a USAF pedíu propostas para un Sistema de Alerta e Control Aerotransportado (AWACS) para substituír aos seus EC-121 Warning Stars, que serviran realizando ese rol durante máis dunha década.