The AD60 was a class of Garratts for freight traffic introduced by the New South Wales Government Railways in 1952. Due to a limited axle load of 16 tons, they had been designed as 4-8-4+4-8-4. They got roller bearings on all axles and the crank pins and had a mechanical stoker. Another feature was that they were the first Garratts to have a cast-steel engine bed. Their running gear could negotiate curves with a radius of 400 feet or 120 metres.
The first order was for 25 locomotives, followed by a second one of 25 more. While the second order was already in production, the NSWGR realized that it was time to concentrate on diesel power. So they negotiated with Beyer-Peacock and managed to cut the order by eight locomotives, for a total of 42. As it turned out that the coal supplies were too small, they were soon increased from 14 to 18 tons.
Soon 30 were subject to another rebuild when it became clear that they were needed for main line traffic. Their cylinder diameter was increased by 3/4 inches while the suspension was rearranged to increase the axle load on each driving axle by more than two tons. They also got dual controls to facilitate running in both directions. The rebuilt variant was designated AD60++ and was also called “Super Garratt”.
Due to the introduction of diesel traction, withdrawals already started in 1961. In 1973, 6042 was the last steam locomotive to haul a revenue service in New South Wales. It is one of four which were preserved, but is in a very bad condition today. Only 6029 is still operational.
