Western Australian Government Railways RA class
RA1918
Type and origin Power type Diesel-electric Builder English Electric, Rocklea Serial number A.202-A.207, A.218-A.222, A.244, A.248 Build date 1968-72 Total produced 13
Specifications Configuration: ​  • AAR C-C  • UIC Co-Co, Co′Co′ Gauge 1,067 mm (3 ft 6 in) Bogies English Electric low weight transfer Wheel diameter 3 ft 1+1⁄2 in (0.953 m) Minimum curve 264 ft (80.467 m) Wheelbase 44 ft 2 in (13.462 m) total, 11 ft 3 in (3.429 m) bogie Length 53 ft 6 in (16.307 m) over headstocks Width 9 ft 4 in (2.845 m) Height 13 ft (3.962 m) Axle load 15.5 long tons (15.7 t; 17.4 short tons) Loco weight 93 long tons (94 t; 104 short tons) Fuel type Diesel Fuel capacity 1,200 imp gal (5,500 L) Coolant cap. 200 imp gal (910 L) Prime mover EE 12CSVT Mk II RPM range 850rpm Engine type four stroke, four valves per cylinder Aspiration turbo, intercooled Generator EE822/16J Traction motors EE548 Cylinders 12 Vee Cylinder size 10 in × 12 in (254 mm × 305 mm) MU working 110V, stepless electro-pneumatic throttle Loco brake Air, proportional control Train brakes Dual air and vacuum
Performance figures Maximum speed 60 miles per hour (97 km/h) Power output 1,950 hp (1,450 kW), gross, 1,795 hp (1,340 kW) net Tractive effort: ​  • Starting 67,000 lbf (298.0 kN)  • Continuous 50,500 lbf (224.6 kN) at 10.8 mph (20 km/h)
Career Operators Western Australian Government Railways Disposition 12 scrapped, 1 preserved

The RA Class are diesel locomotives built by English Electric, Rocklea for the Western Australian Government Railways between 1969 and 1972. They were a revised version of the R class.

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.

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 1973, a version of the RA class with a low nose was ordered for Tasmanian Government Railways, which classed them Z.

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. OCLC 219836193.
• Milne, Rod (1998). Westrail's English Electric Experience (The English Electric locomotives of the WAGR). Elizabeth, SA: Railmac Publications. ISBN 0958650098.

Media related to WAGR R class (diesel) at Wikimedia Commons