The Buzz

Why Russia, China or North Korea Does Not Want to Fight America's M1 Abrams Tank

Army officials came away enthusiastic about the armor but faced considerable skepticism and pushback from the “not invented here” crowd. That was gradually overcome once those involved became aware of how incredibly effective it was. Another issue was engineering-related and much more serious: the new armor had a weight problem.

Although Chobham armor worked very well, fashioning a turret out of it would require the turret to be built of steel welded slabs, unlike the cast turret of the M60. This was not a problem and actually gave the tank a sleek, futuristic look. The problem was that properly armoring the XM-1 would balloon the tank’s weight up from the desired thirty-five to forty tons to fifty-two tons. This in turn affected the vehicle’s mobility, particularly its horsepower to ton weight ratio. The Army’s dream of a lightweight, agile tank was being dashed by its armor requirements.

Meanwhile the service wanted a 1,500-horsepower engine, double the power of the M60’s engine. It tried two diesel engines, the Daimler-Benz diesel that powered the Leopard 2 and a homegrown diesel built by Teledyne Continental, but the third engine, a gas turbine adapted from aircraft use, unexpectedly gained favor. The gas turbine allowed for quicker startups, faster acceleration, ran without producing smoke, and most importantly was smaller and three tons lighter than its competitors, saving valuable weight. Although the gas turbine would require the Army to stock vast quantities of gasoline (in addition to diesel fuel) on the battlefield, the advantages of the turbine eventually won out.

The development of the M1 Abrams is a classic study into how competing requirements can collide with one another. The trifecta of tank power, firepower, protection and mobility all required some level of compromise. The Army was willing to bend some requirements, particularly with regards to weight, to get a good tank instead of being unbending in a vain search for the perfect tank. The result is the most battle-tested main battle tank today, a tank that, with periodic upgrades, has stood the test of time.

Kyle Mizokami is a defense and national-security writer based in San Francisco who has appeared in the DiplomatForeign PolicyWar is Boring and the Daily Beast. In 2009, he cofounded the defense and security blog Japan Security Watch. You can follow him on Twitter: @KyleMizokami.

This first appeared in March. 

Image: Reuters.