The Northrop F-89 Scorpion was an American all-weather, twin-engined interceptor aircraft built during the 1950s, the first jet-powered aircraft designed for that role from the outset to enter service. Though its straight wings limited its performance, it was among the first United States Air Force (USAF) jet fighters equipped with guided missiles and notably the first combat aircraft armed with air-to-air nuclear weapons (the unguided Genie rocket). The Scorpion stemmed from a United States Army Air Forces (USAAF) Air Technical Service Command specification ("Military Characteristics for All-Weather Fighting Aircraft") for a night fighter to replace the P-61 Black Widow. The preliminary specification, sent to aircraft manufacturers on 28 August 1945, required two engines and an armament of six guns, either 0.60-inch (15 mm) machine guns or 20-millimetre (0.79 in) autocannon. The revised specification was issued on 23 November; it did not specify jet propulsion, but the desired maximum speed of 530 miles per hour (460 kn; 850 km/h) virtually dictated that all the submissions would be jet-powered. The aircraft was to be armed with aerial rockets stored internally and six guns split between two flexible mounts, four guns forward and two in the rear. Each mount had to be capable of 15° of movement from the longitudinal axis of the aircraft. Each mount's guns were to be automatically controlled by radar. For ground attack, it had to be capable of carrying 1,000-pound (454 kg) bombs and to be able to carry a minimum of eight rockets externally. There were 15 variants to the F-89 and a total of 2,010 were built. For more information on the development and design, operational history and variants, click here.
