The M1 Abrams is a third-generation main battle tank produced in the United States. It is named after General Creighton Abrams, former Army Chief of Staff and Commander of US military forces in Vietnam from 1968 to 1972. The M1 is a well armed, heavily armored, and highly mobile tank designed for modern armored ground warfare. Notable features of the tank include the use of a powerful gas turbine engine (fueled with JP8 jet fuel), the adoption of sophisticated composite armor, and separate ammunition storage in a blow-out compartment for crew safety. With a weight of close to 68 short tons (almost 62 metric tons), it is one of the heaviest main battle tanks currently in service.