UIC classification of locomotive axle arrangements

The UIC classification of locomotive axle arrangements describes the wheel arrangement of locomotives, multiple units and trams. It is set out in the International Union of Railways (UIC) "Leaflet 650 - Standard designation of axle arrangement on locomotives and multiple-unit sets". It is used in much of the world. The United Kingdom used a related scheme. The United States uses the simplified AAR wheel arrangement for modern locomotives.

Examples
 Bo'Bo' (UK Bo-Bo) Two bogies or wheel assemblies under the unit. Each bogie has two powered axles individually driven by traction motors
 Co'Co' (UK Co-Co) Two bogies or wheel assemblies under the unit. Each bogie has three powered axles individually driven by traction motors
 Co'Bo' (UK Co-Bo) Two bogies or wheel assemblies under the unit. One bogie has three powered axles and the other bogie has two powered axles. All axles are individually driven by traction motors

References

Category:Locomotive classification systems

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