Armor: Three Decade Search For New Light Tank
July 9, 2022: The U.S. Army finally has a new light tank, the 38-ton MPF (Mobile Protected Firepower) vehicle. MPF has not yet received a customary name as the 55-t0n M1 Abrams or 15-ton M551 Sheridan. Both of these looked like tanks but the M1 was a major success while the M551 was not. The army takes its time deciding such mundane matters as official names for new tanks. Obtaining a new light tank is a process that began over 30 years ago just before the M551 was retired from combat service. Some M551s continued to serve as a simulated enemy tank in large scale training exercises at the NTC (National Training Center) until 2003. There were a lot of M551s still available because 1,662 were built between 1966 and 1970. The M551 failed in combat. It had a crew of four and a unique 152mm gun that used twenty onboard 152mm short range shells or nine Shillelagh guided missiles with a max range of 3,000 meters. The 152mm gun was never very reliable and during its only combat experience (Vietnam 1969-72) performance of the M551 and its 152mm main gun were dismal. The M551 152mm gun was unreliable and only used shells in Vietnam to supply infantry with much needed fire support. Only 200 M551s were sent to Vietnam and most were destroyed by enemy fire (RPG rockets or heavy machine-guns) or broke down during use. The 155mm gun had a slow rate of fire and had only 24 shells on board if missiles were not carried. There were often problems with the fire control system. The army came up with several modifications but gave up on the M551 by 1978. The 82nd airborne division kept using them because they could be dropped by parachute and still function.
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