0-2-2

An 0-2-2, in the Whyte notation for the classification of steam locomotives by wheel arrangement, is one that has two coupled driving wheels followed by two trailing wheels, with no leading wheels .

Other equivalent classifications are:

UIC classification: A1 (also known as German classification and Italian classification)

French classification: 011

Turkish classification: 12

Swiss classification: 1/2

The 0-2-2 arrangement was used in the early days of the steam locomotive, and little thereafter. A famous 0-2-2 is Stephenson's Rocket. Its fellow competitor in the Rainhill Trials, John Ericsson and John Braithwaite's "Novelty", was also an 0-2-2. Eight subsequent Stephenson locomotives for the Liverpool and Manchester Railway were of the 0-2-2 type; these were "Meteor", "Comet", "Dart", "Arrow", "Phoenix", "North Star", "Northumbrian", and "Majestic", following which Stephenson locomotives switched to the 2-2-0 "Planet" type. The pioneering American locomotive "Tom Thumb" was also of 0-2-2 configuration.