GWR 7 (Armstrong) Class

Specifications
Specifications
Configuration:;
• Whyte	4-4-0
• UIC	2′B
Gauge	4 ft 8+1⁄2 in (1,435 mm) standard gauge
Leading dia.	4 ft 1.5 in (1.257 m)
Driver dia.	7 ft 0.5 in (2.146 m)
Wheelbase	23 ft 0 in (7.01 m)
Cylinder size	20 in × 26 in (508 mm × 660 mm)

Type and origin
Type and origin
Power type	Steam
Designer	William Dean
Builder	Great Western Railway’s Swindon Works

Armstrong Class
Armstrong Class
	No. 7 Armstrong c. 1900
Power type
Type and origin
Power type	Steam
Designer	William Dean
Builder	Great Western Railway’s Swindon Works
Configuration:;
Specifications
Configuration:;
• Whyte	4-4-0
• UIC	2′B
Gauge	4 ft 8+1⁄2 in (1,435 mm) standard gauge
Leading dia.	4 ft 1.5 in (1.257 m)
Driver dia.	7 ft 0.5 in (2.146 m)
Wheelbase	23 ft 0 in (7.01 m)
Cylinder size	20 in × 26 in (508 mm × 660 mm)

The William Dean 7 or Armstrong Class refers to a group of four prototype 4-4-0 double-frame locomotives built at the Swindon Works of the Great Western Railway in 1894.