The NZR K class of 1932 was a class of mixed traffic 4-8-4 steam locomotives built by the New Zealand Railways Department (NZR) that operated on New Zealand's railway network. The locomotives were developed following the failure of the G class Garratts. The class should not be confused with the much earlier K class of 1877-78, the first American-built engines to arrive in New Zealand. History The three G class locomotives were introduced by NZR in response to increased tonnages, especially on the mountainous, demanding North Island Main Trunk Railway. However, various faults led to their swift withdrawal from service and NZR still needed a large and powerful type of locomotive. It decided to develop a conventional rather than articulated locomotive, to avoid a repeat of the G class failure. Initially conceived as a 4-8-2 locomotive, the K class was to be at least 50% more powerful than the AB class, and due to New Zealand's narrow gauge track and limited loading gauge, the power had to be very carefully compressed into an area smaller than would usually be used for such a locomotive. Constructed at Hutt Workshops, the class utilised plate frames, partial mechanical lubrication, Franklin butterfly Firehole doors, and roller bearings on all but the trailing bogie. The class had a distinctive appearance when first outshopped, with a pressed smokebox front and the headlight jutting out forward of the top of the smokebox. This latter feature was soon changed at the insistence of one of the Railway’s Board of Management – instead, it was sunken flush into the smokebox, which required some modification and changed the aesthetic look of the class quite markedly. K 919 was given an ACFI feedwater heater system as a trial, a feature that was continued on the subsequent KA and KB classes. In service Upon entering service the class were used on heavy freight and express passenger trains. The K class were best known for spectacular running on the mountainous parts of the North Island Main Trunk in the central North Island and on the Marton - New Plymouth Line around Wanganui. In particular, they took over from the X class locomotives which had been used particularly on the Raurimu Spiral. While generally reliable, trouble at first was encountered with the long-travel Walschaerts valve gear, and with the plate frames. While the valve gear problems were largely solved by reducing travel from the