the system had been resolved. The Shillelagh-equipped M60A2s entered service in 1974, but were hampered by reliability problems, and were phased out in 1980. The final revision of the M60A3 used the same 105 mm gun and turret as the M60A1. MBT-70 The most ambitious project based on the Shillelagh was the MBT-70, an advanced US-German tank. Design work on the MBT-70 began in 1963. The tank mounted a huge auto-loader turret on top of a very short chassis, so short that there was no room for a driver in the front hull. Instead of being located in the conventional position, the driver was seated in the turret with the other crew members, in a rotating cupola that kept him facing forward. The gun was a new longer-barreled design, the XM-150, which extended range and performance to the point where it was useful for sabot type rounds as well. However, the project dragged on, and in 1969 the estimated unit cost had risen fivefold. Germany pulled out of the project. The Army proposed a "cut-down" version of the system, the XM-803, but Congress cancelled it in November 1971. It initiated and issued funds to the M1 Abrams project the next month. The M1 design incorporated a conventional gun. See also List of gun-launched missiles XM1111 Mid-Range Munition, U.S. unpowered 120mm guided munition canceled in 2009 References Notes References Starry, Donn A., General. Mounted Combat in Vietnam. Department of the Army, Washington D.C. 1978. External links Ford M13/MGM-51 Shillelagh - Designation Systems Anti-tank guided missiles of the United States Cold War missiles of the United States Military equipment introduced in the 1960s