The first batch of six engines was constructed in 1911. These engines, entered into service with WAGR in 1912, were only the third Garratt design to be produced and represented a significant step in the development of the type. The second batch, which consisted of seven units, was built in 1913/14 and designated as the Ms class due to the use of superheated steam. One of the engines from the first batch was retrofitted with a superheater and given a Ms classification.[2][3]
All of the M/Ms class locomotives were utilized to haul trains on the WAGR's light lines. They were withdrawn from service between 1947 and 1955, and all were scrapped.[1]
The numbers and periods in service of each member of the Ms class were:[1]
Ms class, built by Beyer, Peacock & Co.:
Builder's number
Fleet number
Year built
In service
Withdrawn
Notes
5478
389
1911
12 April 1935
28 September 1950
Converted from M class
5665
424
1913
27 September 1913
4 September 1947
Stowed 25 July 1945
5666
425
1913
4 October 1913
4 September 1947
5667
426
1913
27 September 1913
4 September 1947
5668
427
1913
4 October 1913
4 September 1947
5669
428
1913
4 October 1913
14 February 1952
5670
429
1913
11 October 1913
13 January 1955
5671
430
1913
11 June 1914
29 May 1953
Erected at Midland Railway Workshops, October 1913, for State Saw Mills. In service at Manjimup, November 1913. Transferred to WAGR June 1914 in exchange for G57 & G59.
The M class designation was previously used for the M class locomotives that were withdrawn in 1911. It was reused in the 1970s when the M class diesel locomotives entered service.
Gunzburg, Adrian (1984). A History of WAGR Steam Locomotives. Perth: Australian Railway Historical Society (Western Australian Division). ISBN0959969039.