Victorian Railways 'A2' CLASS 4-6-0

Designed by A.E. Smith.
125 'Stephenson' A2's built at Newport Railway Workshops 1907-1915.
60 'Walschaert' A2's built at Bendigo and Ballarat Railway Workshops 1915-1922.


CYLINDERS 22 ins x 26 ins. (558.8mmx660.4mm)
COUPLED WHEEL DIAMETER 73 ins. (1,854.2mm)
TOTAL HEATING SURFACE
(including superheater) 2,054 square feet. (190.8m²)
GRATE AREA 29 square feet. (2.7m²)
BOILER PRESSURE 185 PSI. (1,275.5 kpa)
TRACTIVE EFFORT 27,480 lbs. (12,464.7 kg)
TOTAL WEIGHT 122 tons. (123.9 tonnes)
LENGTH OVERALL 63 feet 7 ins. (19,380.2mm)

The 'A2' class locomotive first appeared in 1907 as a development of the successful DD class 4-6-0. The first 125 being saturated and employing Stephenson's inside valve gear, all were later fitted with superheaters. The second 60 were built as superheated locomotives and featured Walschaert's outside valve gear.

The 'A2's were for sometime Australia's premier express passenger locomotives until equalled by the NSW NN class 4-6-0 of 1914 and finally being surpassed by the 'C36' class in 1925. They did however remain as the mainstay of the Victorian mainline passenger locomotive fleet. Modifications made over the years included lowered blast pipes and front end draughting improvements, stovepipe chimneys, elephant ear smoke deflectors and on some of the class the fitting of Boxpok driving wheels. Some were also equipped to burn pulverized brown coal whilst a few were converted to oil firing.

The 'A2's enjoyed a long, low-maintenance life and proved to be one of Australia's most successful designs. They were relieved of some of their prestige duties with the introduction of the 'S' class Pacific's in 1928 and the 'R' class Hudsons in 1952, also the diesel revolution in the early '50's relegated them to more mundane workings. The last one, number 986 was withdrawn from service in December 1963. Fortunately a number of the Ten Wheelers remain as static displays at various sites around Victoria.