Under the Whyte notation for the classification of steam locomotives, 4-6-2 represents the wheel arrangement of four leading wheels on two axles, six powered and coupled driving wheels on three axles and two trailing wheels on one axle. The 4-6-2 locomotive became almost globally known as a Pacific type after a locomotive built by the Baldwin Locomotive Works in Philadelphia was shipped across the Pacific Ocean to New Zealand.
New Zealand's Q class, the first true Pacific locomotive
Cape Government Railways Enlarged Karoo Class, SAR Class 5
The LNER Peppercorn Class A1 60163 Tornado, built in 2008
Western Australian Government Railways P class no. 508
The Whyte notation is a classification method for steam locomotives, and some internal combustion locomotives and electric locomotives, by wheel arrangement. It was devised by Frederick Methvan Whyte, and came into use in the early twentieth century following a December 1900 editorial in American Engineer and Railroad Journal.
Whyte notation from a handbook for railroad industry workers published in 1906