W89

The W89 was an American thermonuclear warhead design intended for use on the AGM-131 SRAM II air to ground nuclear missile and the UUM-125 Sea Lance anti-submarine missile. What was to become the W89 design was awarded to the Lawrence Livermore National Laboratory in the mid-1980s. It entered Phase 2A technical definition and cost study in November 1986. It entered Phase 3 development engineering and was assigned the numerical designation W89 in January 1988. The W89 design was a 13.3-inch (33.8 cm) diameter by 40.8-inch (103.6 cm) long weapon, with a weight of 324 pounds (147 kg) and yield according to unofficial information of 200 kilotons. The design was canceled in September 1991 along with the SRAM II missile, prior to production of any units, though some test devices may have been manufactured.