the R-1820 entered production in 1931. Early variants produced by Curtiss-Wright powered aircraft like the Martin B-10. During WWII, it was built under license by Lycoming, Pratt & Whitney Canada, and the Studebaker Corporation. The R-1820 also found limited use in armored vehicles in two forms. The G-200 was a nine-cylinder gas-burning radial that developed 900 hp (670 kW) at 2,300 rpm and powered the M6 Heavy Tank. The Wright RD-1820 was converted to a diesel by Caterpillar Inc. as the D-200 and produced 450 hp (340 kW) at 2,000 rpm in the M4A6 Sherman. The engine remained in production well into the 1950s.