Highland Railway O Class

The Highland Railway O Class locomotives were built as 2-4-0T tank engines, but were soon rebuilt as 4-4-0Ts. They were designed by David Jones for Scottish Railway companies and three were built at the company's Lochgorm Works in 1878 and 1879.

Highland Railway O class
Type and origin Power type Steam Designer David Jones Builder HR Lochgorm Works Build date 1878–1879 Total produced 3
Specifications Configuration: ​  • Whyte 2-4-0T (rebuilt as 4-4-0T)  • UIC 1′B t, rebuilt as 2′B t Gauge 4 ft 8+1⁄2 in (1,435 mm) Leading dia. New: 3 ft 9+1⁄2 in (1.156 m) Rebuilt: 2 ft 7+1⁄2 in (0.800 m) Driver dia. 4 ft 9 in (1.448 m) Loco weight New: 36 long tons 0 cwt (80,600 lb or 36.6 t) Rebuilt: 44 long tons 0 cwt (98,600 lb or 44.7 t) Boiler pressure 140 lbf/in2 (0.97 MPa) Heating surface 913 sq ft (84.8 m2) Cylinders Two, outside Cylinder size 16 in × 22 in (406 mm × 559 mm) Valve gear Allan
Performance figures Tractive effort 12,158 lbf (54.08 kN)
Career Operators Highland Railway → London, Midland & Scottish Class HR: O Power class LMS: unclassified Withdrawn 1928–1932 Disposition All scrapped

Dimensions

They had 4-foot-9-inch (1,448 mm) coupled wheels, 16-by-22-inch (406 by 559 mm) outside cylinders and weight (in original condition) of 36 tons.

Numbering

Table of locomotives

HR No.	Name	Date built	LMS No.	Withdrawn	Notes
58	Burghead	December 1878	15011	1928	Name removed in 1900. Renumbered 58A in 1912 and 58B in 1920
59	Highlander	June 1879	15010	1933	Name removed in 1900. Renumbered 59A in 1912 and 59B in 1920
17	Breadalbane	December 1879	15012	1929	Renamed Aberfeldy in 1886; name removed in 1900. Renumbered 50 in 1901, 50A in 1912, 50B in 1920

Rebuilding

They were rebuilt as 4-4-0Ts in 1881–82 due to trouble with the single leading axle.

Transfer to LMS

All three were still in service in 1923, although relegated to shunting duties, and they were transferred to the London, Midland and Scottish Railway (LMS) at the Grouping.

Withdrawal

The three locomotives were withdrawn and scrapped between 1928 and 1933.