The RA class were a hood type general purpose diesel-electric locomotive. They were similar to the Queensland Railways 1300 class. All equipment, except traction motors, were interchangeable with the standard gauge K class. The main differences with the R class were a slight increase in length and wheelbase and deletion of the dynamic brake. They were otherwise identical mechanically and electrically.
The bogies were identical to those fitted to the R class and were an English Electric design with low weight transfer characteristics. They feature fully equalised primary spring gear, all traction motors in each bogie mounted with the nose-suspension facing inwards, traction thrust at near axle level and long pivot centres to reduce inter-bogie transfer. Adhesion loss at maximum tractive effort is limited to 4.5 per cent allowing 1,830 long tons (1,860 t; 2,050 short tons) trailing load to be hauled up a 1 in 100 grade.
History
Following on from the R class, a further 11 were ordered, but without dynamic brakes. A further two were financed by the Lefroy Salt Company for use over a 13-kilometre (8.1 mi) spur off the Esperance line.[1][2][3][4]
In 1974 the RA1914, RA1917 and RA1918 were fitted with standard gauge bogies and renumbered KA211-KA213.[1][5] RA1918 has been preserved by Rail Heritage WA.[6]
Gunzburg, Adrian (1968). WAGR Locomotives 1940–1968. Perth: Australian Railway Historical Society (Western Australian Division). pp. 35, 48. OCLC219836193.
Milne, Rod (1998). Westrail's English Electric Experience (The English Electric locomotives of the WAGR). Elizabeth, SA: Railmac Publications. ISBN0958650098.
Media related to WAGR R class (diesel) at Wikimedia Commons
