Locomotives of New Zealand
Locomotives of New Zealand currently in operation owned by KiwiRail consist of 172 diesel-electric locomotives, 22 electric locomotives, 3 railcars, and 103 shunting locomotives. There are also 19 diesel multiple units in Auckland, owned by Auckland Transport, 71 electric multiple units owned by the Greater Wellington Regional Council, 57 electric multiple units owned by Auckland Transport, and diesel-electric and steam locomotives and railcars in working order owned by private companies or preservation societies.
All New Zealand's main-line locomotives are 1067 mm (3 foot 6 inch) gauge.
The locomotives of KiwiRail and its predecessors are divided into classes. Each class was designed to perform specific duties. A class can be as small as one individual locomotive, and the largest class to run on New Zealand rails was the DA class, which comprised 146 locomotives.
20 new DL class Chinese-built diesel electric locomotives arrived in mid-2012.
Steam locomotives (which were retired from regular service by the end of October 1971) were originally categorised with just a single letter, such as the "F class". When a new class was built as an enhancement of an old class, the old class's letter was re-used, followed by a superscript upper-case letter. For example, the 1906 A class was followed by the AA and AB classes.
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