Editing 2-10-10-2 (section)

{{Short description|Mallet locomotive wheel arrangement}}
Under the [[Whyte notation]] for the classification of [[steam locomotive]] [[wheel arrangement]]s, a '''2-10-10-2''' is a locomotive with two [[leading wheel]]s, two sets of ten [[driving wheel]]s, and a pair of [[trailing wheel]]s.

Other equivalent classifications are:
:[[UIC classification]]: '''1EE1''' (also known as German classification and [[Swiss classification]])
:[[Italian and French classification]]: '''150+051'''
:[[Turkish classification]]: '''56+56'''
:[[Swiss classification]]: '''5/6+5/6'''

The equivalent [[UIC classification]] is refined to '''(1′E)E1′''' for Mallet locomotives. All 2-10-10-2 locomotives have been [[articulated locomotive]]s of the [[Mallet locomotive|Mallet]] type.

This wheel arrangement was rare. Only two classes of 2-10-10-2 locomotives have been built: the [[Atchison, Topeka and Santa Fe Railway]]'s '''3000 class''', and the [[Virginian Railway]]'s '''class AE'''. The 3000 class performed poorly, so the railroad returned them to their original 2-10-2 configuration after no more than seven years of service. The class AE locomotives were much more successful, providing between 25 and 31 years of service; some were scrapped between 1943 and 1945, and the rest were scrapped between 1947 and 1949. None of either class were preserved.