Commonwealth Railways NSU class

The Commonwealth Railways NSU class class were a class of diesel locomotives built by Birmingham Railway Carriage and Wagon Company for Commonwealth Railways for use on the Central and North Australia Railways in 1954-1955.
By the end of World War II, the Commonwealth Railways were operating a ragged and worn out collection of rollingstock on their Central and North and Trans-Australian lines. Some of the narrow gauge locomotives were fifty or more years old, and the rolling stock not much the younger. Federal Minister for Fuel, Shipping & Transport George McLeay, made recommendations to Cabinet in 1950, to upgrade the Commonwealth Railway's fleet of both narrow and standard gauge locomotives and rollingstock. 
In 1950 a tender was issued for 14 diesel locomotives for the 1,067 mm (3 ft 6 in) narrow gauge lines.Thirteen companies submitted over thirty designs. However, as the specifications were rigid, most did not get past the first stage of the selection procedure. 
The CR's Mechanical Branch also seemed to take preference for slower revving engines. The Sulzer plant finally selected ran at 750 rpm at idle, whereas one design submitted by AE Goodwin ran at 1500 rpm. Finlay[1] noted the "CR Mechanical Branch appeared not to have been overly excited about high revving engines, as it feared they would lead to high repair bills. 1000 rpm was considered fast enough". Finlay also notes that the seemed preference for slower speed engines, as well as the requirement of an electrical transmission resulted in the failure of many of the submitted tenders. 
In 1951, the CR departed from their apparent tradition of using "well proven" designs, and awarded to contract to build the class of locomotives, later to be known as the NSU, to the Birmingham Railway Carriage and Wagon Company Ltd (BRCW). The Sulzer/BRCW design had won over the English Electric Company's (EE) submission. Whilst EE were obviously a better known company (in Australia), having built many other pioneering Diesel Electrics, Sulzer plants had been used widely in the UK (the earliest UK Sulzer diesels were the Armstrong-Whitworth "Universal's" of the 1930s,[2]) and Europe and other exported units, and would go on to power some 690 British Railways machines, using both the 6LDA plant, and later and larger in-line and V- units.
Today all members of the class have survived. As of 2020, however, only one was operational, NSU52. Locomotives 55 and 58 are operable but have not been used in recent times.
==Trivia==
*There are 14 different class locomotives.
Category:Diesel locomotives
Category:Australian locomotives
Category:Six-axled diesel locomotives
Category:Australia
Category:Commonwealth Railways
Category:Locomotives
Category:3 foot 6 inch gauge
Category:Narrow-gauge locomotives
Category:Narrow gauge
Category:Narrow-gauge diesel locomotives
Category:Narrow-gauge