Commonwealth Railways NT class
|Commonwealth Railways NT class|
|NTs 67 and 76 work a south bound grain train through Wirrabarra to Gladstone in 1987|
|Gauge||1,067 mm (3 ft 6 in)|
|Length||51 ft (15.54 m)|
|Axle load||12.9 tonnes (12.7 long tons; 14.2 short tons)|
|Locomotive weight||70 tonnes (69 long tons; 77 short tons)|
|Prime mover||Sulzer 6LDA28C|
|Generator||Associated Electrical Industries type TG.5302W|
|Traction motors||Associated Electrical Industries type 253AZ|
|Top speed||80 km/h (50 mph)|
|Power output||970 kW (1,300 hp)|
|Number||NT65 – NT77|
|First run||12 May 1965|
The NT class was the second Commonwealth Railways diesel locomotive built for service on the Central and North Australia Railways. They were one of two classes of locomotive to use Sulzer traction in Australia.
Taking into account the unique operating environment, and the experience it had with the NSU class, the CR contracted Tulloch Limited to build its new class of locomotive, designated the NT. The contract, however, required Sulzer to provide technical and engineering control to the project.
After the initial batch had been delivered over several years, the CR added an additional three locomotives to the original order to accommodate increased traffic on the Northern Australia Railway, associated with the Frances Creek Mine Project.
NTs 65, 67, 69, 71 and 72 worked ore trains from Broken Hill to Peterborough, then as light engine to Quorn on their delivery runs from New South Wales.
Whilst the NTs were involved in a number of derailments, the most spectatular accident was the runaway into the Frances Bay freight yard that happened on 4 November 1972 - indeed the incident would be a key factor in the closure of the Northern Australia Railway.
At the time, NT70 was at the head of a south bound train ready to leave as soon as the inbound ore train had arrived. At Parap, the service facility for the railway, NT's 75, 71, and 68 replaced the locomotives which had worked the ore train from Frances Creek. However, for some reason, the train's air brakes were not connected, and a brake test was not conducted. As the train rolled down into Frances Bay, it accelerated, and attempts to slow the train were ineffective; the train ran head on into NT70.
NT68 was restored to service in Parap, whilst NTs 70, 71 and 75 were eventually written off.
NTs 69 and 73 went out in a blaze of glory, when, during their scrapping, they caught fire.
Australian National transferred three of the class to its Port Lincoln Operations, in part as a trial to see if the class was suitable for service on bulk grain, gypsum and salt trains.
The three locomotives, NTs 69, 73 and 74, underwent various repairs and servicings prior to the transfer. This included repainting.
The class developed a reputation as powerful pullers, with anecdotal information suggesting that, on more than one occasion, a single NT had hauled a two locomotive load up Pearlah Bank, the ruling grade for south-bound trains.
The NTs worked the entire division, including a short stint on the gypsum and salt trains working from Thevenard. Coincidentally hauling the same iron ore wagons they dragged in the NT, some 15 years earlier.
The cabs of the NTs were cramped, and when under load were subject to high vibrational forces. Combined with their age, and decreasing reliability, the fleet were allocated to shunt duties in Port Lincoln Yard. NTs 69 and 73 were the last operational NTs held by Australian National.
Only NT76 has survived into preservation. It is owned and operated by Pichi Richi Railway (Quorn South Australia)
The majority of the class spent their working lives in the colors of Commonwealth Railways - Maroon with a silver band. The only variation was a name change from "Commonwealth Railways" to "Australian National Railways". NTs 69 and 73 were repainted into Australian Nationals Green and Gold in Port Lincoln in 1985.
- NT65 - Named "Gordon Freeth"; Delivered 24 April 1965; First NT to work over the Quorn line on its delivery 1 May 1965 To Northern Australia Railway (NAR) 13/9/71: To Central Australia Railway (CAR) 1976; Stored Port Augusta 1981; 575,954 km 
- NT66 - Delivered 18 June 1965 via Broken Hill and Quorn; to NAR 4/10/1971; to CAR 1976; Stored Port Augusta 1981; 948,205 km
- NT67 - Delivered 4/8/1965 via Quorn line (10 August 1965); To NAR 14/2/68; To CAR 1976 - used as Marree Narrow Gauge Shunter; Stored Port Augusta 1981; To Peterborough 1 February 1983  To Wilmington Line ~August 1984  - scrapped Gladstone 1989
- NT68 - Delivered 11/11/66; To NAR 5/12/1966; Involved in major accident Darwin Yard 4/11/72; To CAR 1975; Withdrawn at Port Augusta 1978.
- NT69 - Delivered 28 November 1966 via Quorn Line (3 December 1966); To NAR 20 December 1966; to CAR 1976; Stored Port Augusta 1981; To Peterborough 1 February 1983; Last North Australia South and North Bound trains 29/30 June 1976; to Port Lincoln 1984 - First to be repainted AN Corporate green and gold January 1985 following "rough" overhaul; Last mainline train from Rudall 11 April 1988. Last operated 21 June 1988 as Port Lincoln yard shunter  Scrapped Port Lincoln 21 August 1990 
- NT70 - Delivered 11/1/1967; to NAR 23 June 1967; Involved in major accident Darwin Yard 4/11/72; Scrapped 1975 
- NT71 - Delivered 1/2/1968 via Quorn Line (10 February 1968 ) ; To NAR 2/5/1968;Involved in major accident Darwin Yard 4/11/72; Scrapped 1975 
- NT72 - Delivered 21 March 1968 via Quorn Line (28 March 1968 ); To NAR1/7/1968; to CAR 1976; Scrapped in 1978 
- NT73 - Delivered 18 April 1968; to NAR 1/7/1968; to CAR 1976; To Gladstone 16 October 1981; to Port Lincoln ~February 1985 - repainted AN Corporate green and gold February 1985 following complete engine overhaul; Last mainline train from Rudall 11 April 1988; Last operated Port Lincoln 21 September 1988 as yard shunter Scrapped Port Lincoln 21August 1990.
- NT74 - Delivered 1/6/1968;to NAR 18 January 1971;to CAR 1976;To Peterborough 13 November 1981; Used to recover Quorn Line Assets; To Port Lincoln ?1984. Rewired Port Lincoln Workshops; stored following crankshaft failure at 28 July 1987  Scrapped Port Lincoln November 1989.
- NT75 - Delivered 28 June 1969; to NAR 27 August 1968; Involved in major accident Darwin Yard 4/11/72 to CAR 1975 - Scrapped Port Augusta 1975 
- NT76 - Delivered 12/8/1968; To NAR 1/11/1968; to CAR 1976; Last movement on CAR-Marree Yard Shunter 27 March 1980  to Gladstone 5 April 1980; First trip to Booleroo Centre with NSU56 9 April 1980; Used as trailing unit pending sound proofing : withdrawn from service 1986  transferred to Wilmington line ~1986 - Operational - Pichi Richi Railway
- NT77 - Delivered 25 September 1968; To NAR 5/8/1971; to CAR 1976 Scrapped Port Augusta 1976 
- Editorial Staff- Tulloch- Sulzer Diesels for CR have High Power/Weight Ratio; Railway Transportation September 1965 pp27-31
- Personal correspondence AT with Author
- Evans, J 2009; Proceed To Quorn; Railmac Publications ISBN 978-1-86477-066-X
- Harvey, J: 1987:The Never Never Line - The Story of the Northern Australia Railway; Hyland House Publishing - ISBN 0-947062-20-3
- "Locos catch fire" Port Lincoln Times 21 August 1990
- Sampson R; Fluck R 1982; Locomotives of Australian National Mainland Mile End Railway Museum Inc Cowandilla ISBN 0-9595073-1-0
- Perrin S; As Editor - Steamtown Newsletter; Steamtown, Peterborough Railway Preservation Society Inc (now defunct) various editions
- Locomotive Registers Port Lincoln Workshops
- Yates, R 1980 Narrow Gauge Movements Steamtown Newsletter No 9 June 1980 Steamtown Peterborough Railway Preservation Society Inc