LSWR A12 class
LSWR A12 class No. 539 in 1888
Type and origin Power type Steam Designer William Adams Builder LSWR Nine Elms Works (50) Neilson & Co. (40) Build date 1887–1894 Total produced 90
Specifications Configuration: ​  • Whyte 0-4-2  • UIC B1 n2 Gauge 4 ft 8+1⁄2 in (1,435 mm) Driver dia. 6 ft 1 in (1.854 m) Trailing dia. 4 ft 0 in (1.219 m) Boiler pressure 160 lbf/in2 (1.10 MPa) Cylinders Two, inside Cylinder size 18 in × 26 in (457 mm × 660 mm)
Performance figures Tractive effort 15,690 lbf (69.79 kN)
Career Operators London and South Western Railway Southern Railway British Railways Class LSWR: A12 SR: A12 BR: 1MT Nicknames Jubilees Retired 1928–1948 Disposition All scrapped

The A12 locomotives of the London and South Western Railway were built between the years 1887 and 1895 to the design of William Adams. Ninety of the locomotives were built, fifty at Nine Elms Works and forty by Neilson and Company, although the latter together with the final twenty from Nine Elms were officially known as the O4 class. They were unusual for their time, with a wheel arrangement of 0-4-2. This arrangement was used by few of the other railway companies, and never proved popular (although the Great Northern Railway had 150 such locomotives). They bore the nickname "Jubilees", because the first batch appeared in the Golden Jubilee of Queen Victoria's reign.

History

The 90 examples of the class were built in batches, as shown in the following table.

All 90 passed to the Southern Railway in 1923, following the introduction of the Grouping Act.

Withdrawal

Withdrawals started in 1928, with four of the class surviving to Nationalisation. The four operated by British Railways were all withdrawn in its first year (1948), excluding DS3191 which was used for steam supply at Eastleigh Works and lasted until 1951. No members of the class have been preserved.