M551 Sheridan
Light Tank
The M551 Sheridan Armored Reconnaissance/Airborne Assault Vehicle was a U.S. light tank designed to be landed by parachute and to swim across rivers. It was armed with the technically advanced but troublesome M81/M81 Modified/M81E1 152 mm gun/launcher, which fired both conventional ammunition and the MGM-51 Shillelagh guided anti-tank missile.