Missile AGM-48 Skybolt

The AGM-48 Skybolt (originally designated GAM-87) was an air-launched ballistic missile developed by the United States during the late 1950s. The program aimed to provide strategic bombers with the capability to launch nuclear payloads from outside the range of air defenses. The United Kingdom joined the program in 1960 to equip its V bomber fleet. Flight testing began in 1962, experiencing a series of initial failures before the first successful flight on December 19, 1962. The United States canceled the program on December 22, 1962, citing the development of submarine-launched ballistic missiles and land-based intercontinental ballistic missiles, which rendered the air-launched system redundant.

The missile was powered by a two-stage solid-fuel rocket motor. For carriage, it utilized a drag-reducing tailcone that ejected shortly after release from the host aircraft. First-stage flight control was managed by eight movable tail fins, while the second stage utilized a gimballed nozzle. Guidance was provided by an inertial navigation system updated by the carrier aircraft prior to launch. To correct drift during extended flight, the guidance package incorporated an optical star tracker designed to track stars in direct sunlight. This requirement dictated that the missile be mounted externally to maintain the star tracker's unobstructed view of the sky. Warhead options included the W47 thermonuclear warhead, which was later replaced by the W59. The United Kingdom planned to integrate its own Red Snow thermonuclear warhead due to safety concerns regarding the W47 design.

The missile was intended for deployment by the United States Air Force and the British Royal Air Force but was canceled prior to entering active service or seeing combat. Planned carrier aircraft were the B-52, configured to carry four missiles on dual underwing pylons, and the Vulcan bomber, configured to carry two missiles. The unilateral cancellation of the program by the United States led to a diplomatic dispute known as the "Skybolt Crisis," as the United Kingdom had canceled its domestic missile programs in anticipation of receiving the system. The crisis was resolved through the Nassau agreement, which allowed the United Kingdom to acquire the Polaris submarine-launched ballistic missile system instead.