In the mid-1970s, the lengthy MBT-70 joint venture between the United States and the Federal Republic of Germany to produce a main battle tank collapsed due to divergent priorities with the developing weapons system. As a result, each country then pursued its own programme. In the United States, the result was the prototype XM-1, which was delivered to the US Army for field evaluation in 1976.
By 1978, Chrysler Corporation initiated production, and two years later the first operational M1 Abrams third-generation main battle tank entered service, a contemporary of the German Leopard 2 main battle tank. A total of 3,273 M1 tanks were built for the US, introducing to the American arsenal a modern armoured vehicle replacing the latest in the Patton tank series, which had served since the 1950s. The M1 had modern features such as the multi-fuel gas turbine engine and Chobham composite armour, along with computer fire control, NBC (nuclear, biological, chemical) protection and separate ammunition storage in a blowout compartment that enhanced crew survivability in the event of a catastrophic explosion.
