South Australian Railways 500 class (diesel)

The South Australian Railways (SAR) 500 class was a class of diesel-electric locomotives built by Clyde Engineering at their Granville, New South Wales, plant for the South Australian Railways between 1954 and 1955. These locomotives were the first mainline diesel locomotives introduced by the SAR, marking a significant shift away from steam power.

The 500 class locomotives were designed for general purpose use, suitable for both freight and passenger services. They were equipped with EMD 567B 16-cylinder diesel engines, providing a notable increase in power and efficiency compared to the existing steam locomotive fleet.

Their introduction allowed for the faster and more efficient operation of trains across the SAR network, contributing to improved reliability and reduced operating costs. They initially operated across a wide range of lines throughout South Australia.

Over their service life, the 500 class locomotives underwent various modifications and upgrades. Some units were eventually withdrawn from service as newer locomotive classes were introduced, but a number remained operational for several decades. Even after withdrawal from SAR/Australian National service, some examples were preserved or sold to other operators. The 500 class played a pivotal role in the dieselisation of the South Australian Railways and remain an important part of the state's railway history.