"Starting with the M2 Medium Tank, American medium tanks were based on the M2 Light Tank. The method of their creation was as follows: novelties were tried out on a light tank, then the tank was proportionally scaled up in size. Of course, many changes were introduced into the design, like increasing the number of bogeys or return rollers. Overall, this method was successful. However, this was not the first attempt at using this method by American tank designers. The first time they tried it, they got something different…
Choosing Concepts
American tank production began with foreign tanks. This approach was the most correct during the war, as it saved the most precious resource: time. This way, by the end of WWI, the American army ended up with M1917 light tanks, reworked French Renault FTs, and heavy Mk.VIII International tanks, made in the likeness of British heavy tanks. The latter were built using American components, most importantly, Liberty L-12 engines.
The issue with medium tanks was never resolved. By the end of WWI, the Entente only had a Medium Mk.A Whippet in this category, an example hardly worth following. The Medium Mk.A didn't survive for long, and the Mk.B and Mk.C that replaced it were more similar to the heavy "rhombus" tanks…"
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