NZR WAB class

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 The locomotives were progressively withdrawn in the 1960s.

Introduction

The first locomotives, W^S 686 and W^AB 687, were built from the boilers, frames and engine units initially destined for A^B 666 and A^B 667. These entered service in 1917, W^S 686 in Wellington and W^AB 687 at Taumarunui in the central North Island. Fourteen W^S class locomotives were built between 1917 and 1925: one at Addington workshops (686), five at A&G Price, Thames (799-803) and eight at Hillside workshops, Dunedin (764-771). All the W^S class were converted to W^AB in 1932-4. Sixteen W^AB class were built between 1918 and 1926: one at Addington (687), 12 at Hillside (786-795) and three at A&G Price (796-798). In July 1922 the class was introduced on Auckland (until 1930 at Waitematā) to Papakura suburban services. Between 1947 and 1957, 11 W^AB class were converted to A^B class, following Wellington electrification, to reduce axle loads, for use on lighter lines.

Preserved locomotives

Only three examples of the class remain, with two in their original form as W^ABs:

• W^AB 794 was donated by the Ohai Railway Board in 1968 to the New Zealand Railway and Locomotive Society and was moved to the Ferrymead Railway, and displayed for the Rail 125 celebrations in 1988. The locomotive has since been restored and is preserved at Feilding, and has been used on mainline excursions and also on the regular Wellington - Auckland Overlander service.
• W^AB (former W^S) 800 is owned by the Waikato Branch of New Zealand Railway and Locomotive Society and was stored for many years at the Te Awamutu Railway Museum. Following the negotiation of a lease agreement, the engine has been moved to the Glenbrook Vintage Railway for eventual restoration to working order.
• A^B (former W^AB) 795 is preserved at Kingston, for use on the "Kingston Flyer".

See also

• NZR W class
• NZR W^A class
• NZR W^B class
• NZR W^D class
• NZR W^E class
• NZR W^F class
• NZR W^G class
• NZR W^W class
• Locomotives of New Zealand

References

Citations

Bibliography

External links

• NZ Steam locomotives - W^AB class
• Feilding and District Steam Rail Society
• Railway preservation in New Zealand