2-10-2

Under the Whyte notation for the classification of steam locomotives, 2-10-2 represents the wheel arrangement of two leading wheels on one axle, usually in a leading truck, ten powered and coupled driving wheels on five axles, and two trailing wheels on one axle, usually in a trailing truck. In the United States and elsewhere the 2-10-2 is known as the Santa Fe type, after the Atchison, Topeka and Santa Fe Railway that first used the type in 1903.