6-2-0

In the Whyte notation, a 6-2-0 is a railroad steam locomotive that has an unpowered three-axle leading truck followed by a single powered driving axle. This wheel arrangement is associated with the Crampton locomotive type, and in the USA the single class were sometimes referred to as Cramptons.

Other equivalent classifications are:
UIC classification: 3A (also known as German classification and Italian classification)
French classification: 310
Turkish classification: 14
Swiss classification: 1/4

The 6-2-0 was a most unusual wheel arrangement, where the bulk of the locomotive's weight was on the unpowered leading wheels rather than the powered driving wheels, therefore giving poor adhesion. The type was only practicable on the Crampton locomotive with a low boiler and large driving wheels placed behind the firebox.

The only British 6-2-0 was the locomotive Liverpool built in 1848 by Bury, Curtis, and Kennedy for the London and North Western Railway. It was exhibited at The Great Exhibition in 1851 but was only moderately successful and no more were built.

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