The Diesel Electric Rail Motor (DERM) was a

railmotor Railmotor is a term used in the United Kingdom and elsewhere for a railway lightweight railcar, usually consisting of a railway carriage with a steam traction unit, or a diesel or petrol engine, integrated into it. Steam railcars Overview In th ...

operated by the

Victorian Railways The Victorian Railways (VR), trading from 1974 as VicRail, was the state-owned operator of most rail transport in the Australian state of Victoria from 1859 to 1983. The first railways in Victoria were private companies, but when these companie ...

Australia Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...

History

Originally built as a petrol electric rail motor (PERM), they were the longest-lived rail motor on the

, with the first entering service in 1928 and the last being withdrawn in 1991. The rail motor was a standard product of the US Electro-Motive Corporation (a predecessor of

Electro-Motive Diesel Progress Rail Locomotives, doing business as Electro-Motive Diesel (EMD), is an American manufacturer of diesel-electric locomotives, locomotive products and diesel engines for the rail industry. The company is owned by Caterpillar through its sub ...

) and built between 1924 and 1932, albeit to a smaller loading gauge and wider track gauge. The first was imported in 1927, assembled at

Newport Workshops The Newport Railway Workshops is a facility in the Melbourne suburb of Newport, Victoria, Newport, Australia, that builds, maintains and refurbishes Rolling stock, railway rollingstock. It is located between the Williamstown railway line, Willia ...

, and placed in service in 1928. The bodies of the remaining nine were constructed at Newport Workshops using imported equipment and electrical equipment and placed in service between 1930 and 1931. The rail motors were initially powered by a

Winton Motor Carriage Company The Winton Motor Carriage Company was a pioneer United States automobile manufacturer based in Cleveland, Ohio. Winton was one of the first American companies to sell a motor car. In 1912 Winton became one of the first American manufacturers of ...

petrol engine, until these wore out and were replaced in the 1950s by twin GM

Detroit Diesel Series 71 The Detroit Diesel Series 71 is a two-stroke diesel engine series, available in both inline and V configurations, manufactured by Detroit Diesel. The number 71 refers to the nominal displacement per cylinder in cubic inches, a rounding off of ...

engines, with a power output of , derated to match the original generator. A DERM, with a DERM Trailer car attached, ran a regular passenger service on the South Gippsland line in the 1960s and 1970s. By the 1970s, the longest scheduled journey run by a DERM was the

Bendigo Bendigo ( ) is a city in Victoria, Australia, located in the Bendigo Valley near the geographical centre of the state and approximately north-west of Melbourne, the state capital. As of 2019, Bendigo had an urban population of 100,991, makin ...

Robinvale Robinvale is a town on the south bank of the Murray River in north western Victoria, Australia. It is connected by a bridge to Euston on the other side of the river in New South Wales. At the , Robinvale had a population of 3,313, however a p ...

run, last operated on 3 June 1978. In 1976, RM 56 was fitted with a new seating arrangement, including rotating seats, using components from the Z carriage fleet. Capacity was reduced to 34 passengers, because the new seating arrangement was two either side of the central aisle rather than the previous two and three. The first-class end of the vehicle was moved towards the centre, closer to the engine, but providing a smoother ride by averaging the suspension of both bogies rather than just one. The trial arrangement was used on the Yarrawonga line, but patronage did not increase sufficiently to justify the retention of that service. Following the changes to 56RM, 55RM and 61RM were extensively modified in the late 1970s, with the engines relocated, the body extended, and a new seating arrangement provided. The most obvious external difference was the fitting of aluminium-framed windows on the driver's cabin, and porthole windows for the engine room. These "Super DERMs" were a familiar sight on the adjoining Mornington and Stony Point lines prior to the early 1980s.

Details of vehicles

Motor units

Trailers

Preservation

All but one of the DERMs have survived into preservation, with 57RM being the only DERM to have been scrapped. Four are operational, with the remaining five in various conditions, generally as a source of spare parts with long-term restoration in mind. Of the regular DERMs, 58RM regularly runs tours on the Melbourne and Victorian broad gauge system, operated by the Diesel Electric Rail Motor Preservation Association of Victoria, and 63RM runs trips on the Daylesford line with trailer 26MT when appropriate. 55RM is allocated to the

Australian Railway Historical Society Museum The Newport Railway Museum is located on Champion Road, Newport, Victoria, near the North Williamstown station. History The museum opened on 10 November 1962, after the Australian Railway Historical Society (ARHS) Victorian Division was allocat ...

but was sub-allocated to the

South Gippsland Railway The South Gippsland Railway was a tourist railway located in South Gippsland, Victoria, Australia. It controlled a section of the former South Gippsland railway line between Nyora and Leongatha, and operated services from Leongatha to Nyora, ...

. When the latter closed in 2016, it moved to the

Yarra Valley Tourist Railway The Yarra Valley Railway is a heritage railway operating on a section of the former Healesville railway which operated between Lilydale and Healesville in the Yarra Valley area northeast of Melbourne, Australia. History The Lilydale-Melbo ...

. 61RM operates on the

Victorian Goldfields Railway The Victorian Goldfields Railway is a broad gauge tourist railway in Victoria, Australia. It operates along a formerly disused branch line between the towns of Maldon and Castlemaine. History The original line was opened on 16 June 1884, open ...

between

Maldon Maldon (, locally ) is a town and civil parish on the River Blackwater, Essex, Blackwater estuary in Essex, England. It is the seat of the Maldon District and starting point of the Chelmer and Blackwater Navigation. It is known for Maldon Sea ...

and

Castlemaine Castlemaine may mean: * Castlemaine, Victoria, a town in Victoria, Australia ** Castlemaine Football Club, an Australian rules football club ** Castlemaine railway station * Castlemaine, County Kerry, a town in Ireland * Castlemaine Brewery, Western ...

References