WAGR P and Pr Classes - Service History

Service History

The P class locomotives proved to be an excellent design, being free steaming and easy to operate. They quickly reduced the need for bank engines which were normally need to provide extra power up the steep gradients across the Darling Scarp. In addition to saving time and resources, this freed up additional badly needed locomotives. Better economy also allowed for higher running distances without stops for resupply and higher speeds made for more efficient running of the expresses on which the P class served, primarily on the Great Southern Railway and Eastern Goldfields railways to Albany and Kalgoorlie respectively. Experiments into engine pooling with the P class on the GSR in 1932 led to the adoption of this practice across the system, freeing up further locomotives for other duties.

The introduction of the Pr class revolutionised passenger travel, and as part of a national commitment to shaving a day off the transcontinental express the WAGR introduced the Westland Express in 1938. The use of Pr class locomotives helped to reduce travel times across the West Australian stage of the journey by more than two hours, accompanied by an increase in the permissible load of 300tons by additional 20.

During the 1940s both P and Pr class locomotives were used extensively on troop trains, while civilian patronage also increased during this time. The increased war traffic was so great that it necessitated the conversion of the 8 P class locomotives to Pr standard at a time when lack of available resources and labour had stalled the production of new locomotives, such as the S class until 1943. Both during and following the war the Pr class remained the premier express locomotive, while the P class continued on secondary passenger services, concentrated in the states' South West around Albany, particularly on the GSR.

The introduction in 1949 of thirty-five Pm and Pmr class Pacifics was originally intended to oust the Pr locomotives from express services the later designs proved unstable at speed and were transferred instead to fast goods workings, leaving the Pr class as the only express locomotive in the WAGR. The introduction of X class Diesels in 1954, however, ended their long tenure in this position and both P and Pr class locomotives were gradually relegated to goods and shunting duties. Their adequate tractive effort and economy, however, ensured their survival until the very end of steam.

The P class were withdrawn between January 1968 and October 1969. With the exception of Pr 528 Murray, which was destroyed by a fire while on-shed at Kalgoorlie in 1950 following an oil leak while operating as an oil-burner, the Pr class were withdrawn between September 1967 and 1970 when class leader Pr 521 Ashburton became the last to be withdrawn on 10 September.