4-12-2

Under the Whyte notation for the classification of steam locomotives, 4-12-2 represents the wheel arrangement of four leading wheels, twelve coupled driving wheels, and two trailing wheels. Other equivalent classifications are:AAR wheel arrangement: 2-F-1UIC classification: 2′F1′ (also known as German classification and Italian classification)French classification: 261Turkish classification: 69Swiss classification: 6/9 This arrangement was named the Union Pacific type, after the only railroad to use it.

4-12-2

Under the Whyte notation for the classification of steam locomotives, 4-12-2 represents the wheel arrangement of four leading wheels, twelve coupled driving wheels, and two trailing wheels. Other equivalent classifications are:AAR wheel arrangement: 2-F-1UIC classification: 2′F1′ (also known as German classification and Italian classification)French classification: 261Turkish classification: 69Swiss classification: 6/9 This arrangement was named the Union Pacific type, after the only railroad to use it.