The C-4B Açor is a two-seat variant of the C-4 fighter family, developed by IPA in the late 1950s to enhance the strike, operational training and mission coordination capabilities of the Portuguese Air Force.
Derived directly from the single-seat C-4A, the C-4B features an extended fuselage to accommodate a second crew member while retaining the same general performance, airframe structure and propulsion system. The addition of a second seat significantly improved effectiveness in fighter-bomber operations, particularly in complex operational environments where navigation, target identification and tactical coordination were essential.
The C-4B entered operational service in the mid-1960s and played a notable role during the Portuguese Colonial War, operating from bases in Africa. It was widely employed in close air support, interdiction and ground-attack missions, earning a reputation for robustness, ease of maintenance and versatility.
The aircraft was primarily operated by Squadron 702 “Escorpiões”, based in Tete, Mozambique, becoming one of the most recognizable variants of the C-4 family. Throughout its service life, the C-4B received incremental upgrades in avionics and weapon systems, extending its operational relevance until the late 1970s, when it began to be gradually replaced by more modern aircraft.
The C-4B Açor helped establish Portugal as a capable designer and producer of effective combat aircraft tailored to its specific operational needs.