The M551A1 Sheridan AR/AAV was an armored reconnaissance and airborne assault vehicle with turret armament that included a 152mm gun and launcher, an M-219 7.62 caliber machine gun mounted coaxially, an M-2 .50 caliber machine gun, and eight M-176 grenade launchers. Combat loaded, it weighed 36,000 pounds, had a cruising range of 373 miles, a maximum speed of 43 miles per hour, was amphibious and air droppable, and carried a crew of four: driver, loader, gunner, and tank commander.