NZR NA class

The NZR N^A class was a class of two steam locomotives that operated on the privately owned Wellington and Manawatu Railway (WMR) and then the publicly owned New Zealand Railways (NZR). Ordered by the WMR to operate on its line up the west coast of the North Island north of Wellington, the first was built in 1894 by the Baldwin Locomotive Works and entered service that year as WMR No. 14. In 1896, a second locomotive that was slightly more powerful was ordered from Baldwin, and it entered service in October 1897. The engines were similar to the two members of the N class ordered in 1891, except they were heavier and more powerful. They were Vauclain compound locomotives.

NZR NA class
Type and origin Power type Steam Builder Baldwin Locomotive Works Serial number 13913, 15054 Build date 1894, 1896 Total produced 2
Specifications Configuration: ​  • Whyte 2-6-2  • UIC 1′C1′ n Gauge 3 ft 6 in (1,067 mm) Driver dia. 49 in (1.245 m) Length 50 ft 10 in (15.49 m) Adhesive weight 25 long tons 4 cwt (56,400 lb or 25.6 t) 25 long tons 4 hundredweight (25.6 t; 28.2 short tons) Loco weight 35 long tons 4 cwt (78,800 lb or 35.8 t) 35 long tons 4 hundredweight (35.8 t; 39.4 short tons) Tender weight 19 long tons 2 cwt (42,800 lb or 19.4 t) 19 long tons 2 hundredweight (19.4 t; 21.4 short tons) Total weight 54 long tons 10 cwt (122,100 lb or 55.4 t) 54 long tons 10 hundredweight (55.4 t; 61.0 short tons) Fuel type Coal Fuel capacity 3 long tons 0 cwt (6,700 lb or 3 t) 6 long tons 0 hundredweight (6.1 t; 6.7 short tons) Water cap. 1,500 imp gal (6,800 L; 1,800 US gal) Firebox: ​  • Grate area 16.7 sq ft (1.55 m2) Boiler pressure 180 lbf/in2 (1,241 kPa) Heating surface 957 sq ft (88.9 m2) Superheater None Cylinders Four (Vauclain compound) High-pressure cylinder 10 in × 20 in (254 mm × 508 mm) Low-pressure cylinder 17 in × 20 in (432 mm × 508 mm)
Performance figures Tractive effort 9,700 lbf (43.15 kN)
Career Operators Wellington and Manawatu Railway, New Zealand Government Railways Numbers WMR 14, 15 NZR 459, 460 Locale Frankton, Wairarapa, Wellington - Longburn section Withdrawn 1929 Disposition Withdrawn

In 1908, the WMR was incorporated into the national network and the government's Railways Department reclassified the engines as the sole members of the N^A class: No. 14 became N^A 459 and No. 15 became N^A 460. They operated for roughly another two decades; N^A 459 spent its final days working in Frankton near Hamilton and was withdrawn from service in March 1929, while N^A 460's last depot was Cross Creek at the Wairarapa end of the Rimutaka Incline and it was withdrawn in July 1929.

External links

• New Zealand steam locomotives — N^A class
• Works Photograph of N^A class
• Drawing of an N^A class locomotive by Derek Brown

References

Bibliography

• Millar, Sean (2011). The NZR Steam Locomotive. Wellington: New Zealand Railway and Locomotive Society. ISBN 978-0-908573-89-9.
• Palmer, A. N.; Stewart, W. W. (1965). Cavalcade of New Zealand Locomotives. Wellington: A H. & A W. Reed. ISBN 978-0-207-94500-7.
• Stewart, W. W. (1974). When Steam was King. Wellington: A. H. & A. W. Reed Ltd. ISBN 978-0-589-00382-1.