New Zealand DE class
DE 504 in service for Taieri Gorge Railway, shunting at Dunedin.
Type and origin
Power typeDiesel-electric
BuilderEnglish Electric, Preston, United Kingdom
Build date1951–1952
Specifications
Configuration:
 • UICBo-Bo
Gauge3 ft 6 in (1,067 mm)
Wheel diameter3 ft (0.914 m)
Wheelbase24 ft 6 in (7.468 m) total, 8 ft (2.438 m) bogie
Length38 ft 3 in (11.659 m) over couplers
Width8 ft 5 in (2.565 m)
Height11 ft 5 in (3.480 m)
Axle load13 long tons (13.2 t; 14.6 short tons)
Loco weight50.8 long tons (51.6 t; 56.9 short tons)
Fuel typeDiesel
Fuel capacity300 imp gal (360 US gal; 1,400 L)
Prime moverEnglish Electric 6SRKT Mk I
RPM range450 - 750 rpm
Engine typefour stroke, two valves per cylinder
Aspirationturbocharged
Traction motorsFour
Cylinders6 Inline
Cylinder size10 in × 12 in (254 mm × 305 mm)
Loco brakeAir
Train brakesAir
Performance figures
Maximum speed55 miles per hour (89 km/h)
Power output660 hp (490 kW) gross, 600 hp (450 kW) net
Tractive effort12,700 lbf (56.5 kN) at 15 mph (20 km/h)
Career
Number in class15
Numbers501–515 (original)
1308–1458 (TMS)
First run20 May 1952
Last runJanuary 1989
RetiredApril 1984 – January 1989
Disposition8 scrapped
7 preserved

The New Zealand DE class[nb 1] was a class of fifteen diesel-electric shunting locomotives, introduced by the New Zealand Railways (NZR) with an intention to replace steam locomotives on shunting duties with diesel power. The class was physically similar to the Tasmanian Government Railways X class, which was also of English Electric design.

In service

Although these locomotives were originally intended to be used as heavy transfer shunters, four of them were used in pairs, each crewed, on the Royal Train tour of Queen Elizabeth II during her visit to New Zealand in 1953-1954. The class also underwent trials for use in suburban passenger trains in Auckland and Wellington, as well as on lesser regional passenger services and branch line freight.[1]

The class was also the first to run on the new Murupara Branch, initially for construction and later for log trains on the still unsettled track bed.[2] This has given it the unofficial status of being the first mainline diesel-electric locomotive in the NZR service, although this title correctly belongs to another class, the DF class of 1954, also manufactured by English Electric.

The introduction of the Traffic Monitoring System (TMS) in 1979 saw the locomotives being renumbered DE1308 – DE1458.

Initially, the class was based in the North Island, but in 1981, four of the locomotives were sent to the South Island. Over time, the class was gradually dispersed to secondary yards on the network, such as Napier, Dunedin, and Invercargill. In the early 1980s, two class members were fitted with English Electric 6SRKT Mk 2 engines, which were also used in the DG class locomotives.[3]

Withdrawal and Preservation

As part of the New Zealand Railways Corporation's plan to reduce the number of first-generation diesels in the late 1980s, a number of the class were scrapped or sold for preservation.

Out of the original fifteen DE class locomotives, seven have survived. All have operated in preservation at least once:

References

Footnotes

  1. ^ Following the introduction of the Traffic Monitoring System (TMS) in 1979, the class classification was capitalised, whereas previously the second letter was a smaller capital letter, that is DE

Citations

  1. ^ "Our First Diesel-Electric Locomotives - Some Notes on the "DE" class". New Zealand Railway Observer. 46 (2). New Zealand Railway and Locomotive Society: 49. Winter 1989. ISSN 0028-8624.
  2. ^ Churchman & Hurst 2001, p. 114.
  3. ^ "DE class of 1952". English Electric Railway Traction in New Zealand. Retrieved 15 February 2017.
  4. ^ "FRONZ Journal #156 - July 2015" (PDF). FRONZ. July 2015. Archived from the original (PDF) on 22 January 2016. Retrieved 19 January 2017.

Bibliography

  • Barry, Colin; Brouwer, John; Dash, Colin; Dickenson, Peter; Shalders, Bruce (1988). Cavalcade 125. Ferrymead 125 Committee. Retrieved 22 March 2019.
  • Churchman, Geoffrey B; Hurst, Tony (2001) [1990, 1991]. The Railways of New Zealand: A Journey through History (Second ed.). Transpress New Zealand. ISBN 0-908876-20-3.
  • McGavin, T A (1983). NZR Locomotives and Railcars 1983. Wellington, New Zealand: New Zealand Railway and Locomotive Society.
  • McClare, E J (1980). New Zealand Railway Diesels. Wellington, New Zealand: Southern Press. ISBN 9780907769286.