M551 Sheridan • Tank M551 Sheridan (USA) • ~118k tris • 5 UV sets 4k M551, Sheridan - US light airborne amphibious tank. In 1963, the tank passed military tests and was recommended for adoption by reconnaissance and airborne units of the US Army; tanks began to arrive in units in 1966. The M551 embodied a number of the latest design solutions for that time: a hull made of aluminum armor, widespread use of plastics, a cannon-launcher capable of firing the Shileila guided missile, etc. Since January 1969, the M551 was intensively used in the Vietnam War.