New Zealand DX class locomotive

The New Zealand DX class locomotive is a class of 49 Co-Co diesel-electric locomotives that currently operates on New Zealand's national railway network.

Built by General Electric in Erie, Pennsylvania, United States, they were introduced to New Zealand between 1972 and 1976. The class is based on the General Electric U26C model, a narrow-gauge version of the GE U23C model. The U26C is also used in South Africa (see South African Class 34-900), Brazil, Kenya, Tanzania and Zambia.

The locomotives have seen several upgrades since their introduction and three versions now exist; the DXB, DXC and DXR.

Introduction

The D^X class was introduced in response to a requirement for a more powerful locomotive to handle traffic on the North Island Main Trunk (NIMT). Before their introduction the heaviest freight and passenger trains on the line required two members of the 1,060-kilowatt (1,420 hp) D^A class to haul them. The D^X class could haul heavier and faster trains than two D^A's, even though they produced 70 kilowatts less than the combined D^A's, as the single D^X weighed 97.5 tonnes compared to the two D^A's combined weight of 162 tonnes.