The project of this large twin-jet with variable-geometry wings, was developed in the 60s to supply the American air forces with a common aircraft doubling the roles of long-range interceptor and bomber. In view of the complexity of the new technologies adopted for it, the set-up stage dragged on for many years before the F-11 reached its operational maturity as the Vietnam War went through its final phase. On that occasion, the plane performed well, thanks to its excellent electronic equipment, which made it one of the first all-weather planes, combined with its premium low flying qualities while carrying a heavy bomb load.