Commonwealth Railways NM class

The Commonwealth Railways NM class is a class of 4-8-0 locomotives owned by the Commonwealth Railways, Australia. The class operated on 1067 mm (3 ft 6 in) narrow gauge lines in South Australia and the Northern Territory.

Commonwealth Railways NM class
Preserved NM34 at the National Railway Museum, Port Adelaide in 2010
Type and origin Power type Steam Builder Thompson & Co, Castlemaine, Victoria Build date 1925-1927 Total produced 22
Specifications Configuration: ​  • Whyte 4-8-0 Gauge 1067 mm (3 ft 6 in) Fuel type Coal Firebox: ​  • Grate area 18.5 sq ft (1.72 m2) Boiler pressure 160 psi (11 bar; 1,100 kPa) Cylinder size 17 in × 22 in (432 mm × 559 mm)
Performance figures Tractive effort 18,085 lbf (80.45 kN)
Career Operators Commonwealth Railways Numbers NM15-NM28 NM31-NM38 First run June 1925 Preserved NM25, NM34 Current owner National Railway Museum Pichi Richi Railway Disposition 2 preserved, 20 scrapped

History

Between June 1925 and December 1927, the Commonwealth Railways took delivery of 22 locomotives built by Thompson & Co, Castlemaine, Victoria for use on the Central Australia Railway. Their design was the same as the Queensland Railways C17 class, but with larger tenders and vacuum brakes rather than air brakes.^[1][2]

The final locomotive, dispatched to the North Australia Railway, was moved to the Central Australia Railway in 1941.^[2]

Eighteen were converted to burn oil during the 1949 Australian coal strike and were converted back to coal burning after the strike ended. All were withdrawn between 1954 and 1956 as NSU class diesel-electric locomotives entered service.^[1]

Preservation

Two have been preserved: NM25 in operational condition at the Pichi Richi Railway^[3] and NM34 on static display at the National Railway Museum, Port Adelaide.^[4]

NM class locomotive no. 25, operated by the Pichi Richi Railway