The M247 Sergeant York DIVAD (Division Air Defense) was a self-propelled anti-aircraft gun (SPAAG), developed by Ford Aerospace in the late 1970s. Based on the M48 Patton tank, it replaced the Patton's turret with a new one that featured twin radar-directed 40 mm rapid-fire guns. The vehicle was named after Sergeant Alvin York, a famous World War I hero.
The Sergeant York was intended to fight alongside the M1 Abrams and M2 Bradley fighting vehicles in the U.S. Army, in a role similar to the Soviet ZSU-23-4 and German Gepard. It would replace the M163 Vulcan Air Defense System and MIM-72 Chaparral. Despite the use of many off the shelf technologies that were intended to allow rapid and low-cost development, a series of technical problems and massive cost overruns resulted in the cancellation of the project in 1985. (courtesy of Wikipedia)