Midland Railway 990 Class

Specifications
Specifications
Configuration:;
• Whyte	4-4-0
• UIC	2′B n2, later 2′B h2
Gauge	4 ft 8+1⁄2 in (1,435 mm) standard gauge
Leading dia.	3 ft 3+1⁄2 in (1.003 m)
Driver dia.	6 ft 6+1⁄2 in (1.994 m)
Loco weight	58 long tons 5 cwt (130,500 lb or 59.2 t)
Fuel type	Coal
Boiler	MR type G9A, later G9AS
Boiler pressure	200 lbf/in2 (1.38 MPa)
Cylinders	Two, inside
Cylinder size	20+1⁄2 in × 26 in (521 mm × 660 mm)
Valve gear	Deeley

Type and origin
Type and origin
Power type	Steam
Designer	Richard Deeley
Builder	Derby Works
Build date	1907–1909
Total produced	10

Midland Railway 990 class
Midland Railway 990 class
	The official photograph of 990 in photographic grey livery
Power type
Type and origin
Power type	Steam
Designer	Richard Deeley
Builder	Derby Works
Build date	1907–1909
Total produced	10
Configuration:;
Specifications
Configuration:;
• Whyte	4-4-0
• UIC	2′B n2, later 2′B h2
Gauge	4 ft 8+1⁄2 in (1,435 mm) standard gauge
Leading dia.	3 ft 3+1⁄2 in (1.003 m)
Driver dia.	6 ft 6+1⁄2 in (1.994 m)
Loco weight	58 long tons 5 cwt (130,500 lb or 59.2 t)
Fuel type	Coal
Boiler	MR type G9A, later G9AS
Boiler pressure	200 lbf/in2 (1.38 MPa)
Cylinders	Two, inside
Cylinder size	20+1⁄2 in × 26 in (521 mm × 660 mm)
Valve gear	Deeley
Tractive effort
Performance figures
Tractive effort	23,662 lbf (105.3 kN)
Operators
Career
Operators	Midland Railway; London, Midland and Scottish Railway;
Class	MR: 990
Power class	4P
Numbers	990–999 (801–809 from 1926)
Withdrawn	1925–1929
Disposition	All scrapped

The Midland Railway 990 class was a class of 4-4-0 steam locomotive with simple expansion. Ten were built by the Midland Railway in 1907–1909. They shared many features with the 1000 class compounds. Initially built as saturated, from 1910 to 1914 they were equipped with superheated boilers. These locomotives were notable for their work north of Leeds, over the difficult Settle and Carlisle route.