LSWR X6 class

4 ft 8+1⁄2 in (1,435 mm)Leading dia.3 ft 7 in (1.092 m)Driver dia.6 ft 7 in (2.007 m)Length54 ft 5+3⁄8 in (16.60 m)Height13 ft 2+3⁄4 in (4.03 m)Fuel typeCoalBoiler pressure175 psi (1.21 MPa)CylindersTwo, outsideCylinder size19 in × 26 in (483 mm × 660 mm)

Performance figures
Tractive effort	17,673 lbf (78.6 kN)

Career
Operators	LSWR · Southern Railway
Class	X6
Power class	SR: I
Withdrawn	1933–1946
Disposition	All scrapped

The LSWR X6 class was a class of express passenger 4-4-0 steam locomotives designed for the London and South Western Railway by William Adams. Ten were constructed at Nine Elms Locomotive Works between 1895 and 1896.

The class were numbered 657–666, and just as the T3 class were a smaller-wheeled version of the X2 class, the X6 class were a smaller-wheeled version of the T6 class. The boiler was identical to that used the T6 class.^[1] Some of the engines were subsequently fitted with a Drummond boiler, including No. 658 which was the last Adams 4-4-0 to remain in service.^[2]

Table of locomotive orders

Year	Order	Quantity	LSWR Numbers	Notes
1895	X6	10	657–666

All passed to the Southern Railway at the grouping in 1923. Withdrawals started in 1933, and by the start of World War II, only six remained. Five were retired during the war, leaving only No. 658, which was withdrawn in December 1946. All were scrapped.

Table of withdrawals

Year	Quantity in service at start of year	Quantity withdrawn	Locomotive numbers	Notes
1933	10	2	662, 665
1936	8	3	660, 661, 663
1940	5	1	657
1942	4	1	664
1943	3	2	659, 666
1946	1	1	658