LSWR A12 class

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.

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

History

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

Year	Order	Builder	Quantity	LSWR numbers	Notes
1887	A12	LSWR Nine Elms	10	527–536	[1]
1888	E1	LSWR Nine Elms	10	537–546	[1]
1889	M2	LSWR Nine Elms	10	547–556	[1]
1893–94	O4	LSWR Nine Elms	10	597–606	[1]
1892–93	—	Neilson & Co. 4506–4545	40	607–646	[2]
1894–95	K6	LSWR Nine Elms	10	647–656	[1]

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 The four operated by British Railways were all withdrawn in its first year (1948), excluding DS3191 which was used for steam supply at Eastleigh Works and lasted until 1951.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.

Table of withdrawals

Year	Quantity in service at start of year	Quantity withdrawn	Locomotive numbers	Notes
1928	90	6	E529, E535, E542, E548, E552, E553
1929	84	13	E528, E531–E533, E536, E537, E540, E543, E544, E547, E549, E550, E556
1930	71	3	E527, E539, E546
1931	68	6	E530, E534, E538, E541, E545, E554
1932	62	6	551, 607, 608, 610, 653, 656
1933	56	9	602, 604, 626, 631, 633, 639, 645, 647, 651
1934	47	1	601
1935	46	3	603, 621, 635
1936	43	4	605, 616, 622, 655
1937	39	4	611, 619, 632, 640
1938	35	3	617, 628, 650
1939	32	1	646	613, 620, 624, 625, 629, 642, 644 withdrawn and then reinstated
1944	31	1	555
1946	30	12	599, 600, 606, 612, 613, 615, 620, 623, 637, 641, 644, 649	612 transferred to Departmental stock as 3191S, later BR DS3191; scrapped 1951
1947	18	14	597, 598, 609, 614, 624, 625, 630, 634, 638, 642, 643, 648, 652, 654
1948	4	4	618, 627, 629, 636