NZR WAB class

Specifications
Specifications
Configuration:;
• Whyte	4-6-4T
Gauge	3 ft 6 in (1,067 mm)
Wheel diameter	54 in (1.372 m)
Wheelbase	33 ft 1 in (10.08 m)
Length	44 ft 6 in (13.56 m)
Adhesive weight	41.85 long tons (42.52 t; 46.87 short tons)
Loco weight	74 long tons (75 t; 83 short tons)
Fuel type	Coal
Fuel capacity	3.0 long tons (3.0 t; 3.4 short tons)
Water cap.	1,700 imp gal (7,700 L; 2,000 US gal)
Firebox:
• Grate area	33.0 sq ft (3.07 m2)
Boiler pressure	200 psi (1,379 kPa)
Heating surface	1,050 sq ft (98 m2)
Superheater:;
• Heating area	183 sq ft (17.0 m2)
Cylinders	Two
Cylinder size	17 in × 26 in (432 mm × 660 mm)

Type and origin
Type and origin
Power type	Steam
Builder	NZR Addington Workshops, Christchurch (1+1) ; NZR Hillside Workshops, Dunedin (12+8) ; A&G Price, Thames (3+5)
Build date	1939

NZR W^AB class
NZR WAB class
	WAB 794 on its first excursion after restoration, with the Capital Connection rolling stock, on 31 August 2003.
Power type
Type and origin
Power type	Steam
Builder	NZR Addington Workshops, Christchurch (1+1) ; NZR Hillside Workshops, Dunedin (12+8) ; A&G Price, Thames (3+5)
Build date	1939
Configuration:;
Specifications
Configuration:;
• Whyte	4-6-4T
Gauge	3 ft 6 in (1,067 mm)
Wheel diameter	54 in (1.372 m)
Wheelbase	33 ft 1 in (10.08 m)
Length	44 ft 6 in (13.56 m)
Adhesive weight	41.85 long tons (42.52 t; 46.87 short tons)
Loco weight	74 long tons (75 t; 83 short tons)
Fuel type	Coal
Fuel capacity	3.0 long tons (3.0 t; 3.4 short tons)
Water cap.	1,700 imp gal (7,700 L; 2,000 US gal)
Firebox:
• Grate area	33.0 sq ft (3.07 m2)
Boiler pressure	200 psi (1,379 kPa)
Heating surface	1,050 sq ft (98 m2)
Superheater:;
• Heating area	183 sq ft (17.0 m2)
Cylinders	Two
Cylinder size	17 in × 26 in (432 mm × 660 mm)
Maximum speed
Performance figures
Maximum speed	60 mph (97 km/h)
Power output	1,000 bhp (750 kW)
Tractive effort	22,250 lbf (99.0 kN)
Number in class
Career
Number in class	30 (16 WAB+14 WS)
Numbers	687 - 798
Locale	All of New Zealand
First run	1918 - 1926
Retired	1967 - 1972
Scrapped	1969 - 1972
Current owner	Feilding and District Steam Rail Society (1)
Disposition	Scrapped, three preserved

The NZR W^AB class locomotives were steam locomotives designed, built and used by New Zealand Railways Department (NZR). Their wheel arrangement is described by the Whyte notation 4-6-4T. The locomotives were designed by NZR chief draughtsman S.H. Jenkinson as tank versions of the A^B class 4-6-2 Pacific locomotive. Initially, the locomotives were separated into two classes, designated W^AB for mainline work and W^S for suburban work.

The remaining locomotives were kept in service until the last days of steam, operating short-haul mainline freight services and fast suburban services, particularly in Auckland. W^AB 794 was sold to the Ohai Railway Board in Southland for running heavy coal trains. The locomotives were progressively withdrawn in the 1960s.