LNER Class A8

The London and North Eastern Railway (LNER) Class A8 was a type of 4-6-2T steam locomotive, designed by both Vincent Raven and Nigel Gresley. They were rebuilt from the LNER Class H1s, a 4-4-4T class.

LNER Class A8
A8 4-6-2T No. 69873 at Middlesbrough Locomotive Depot 1954
Type and origin Power type Steam Designer Vincent Raven and Nigel Gresley Build date 1931–1936 Total produced 45
Specifications Configuration: ​  • Whyte 4-6-2T  • UIC 2′C1′ h3t Leading dia. 3 ft 1+1⁄4 in (0.946 m) Driver dia. 5 ft 9 in (1.753 m) Trailing dia. 3 ft 9 in (1.143 m) Wheelbase 33 ft 3 in (10.13 m) Length 42 ft 6 in (12.95 m) Axle load 17.8 long tons (18.1 t; 19.9 short tons) Loco weight 86.8 long tons (88.2 t; 97.2 short tons) Fuel capacity 4 long tons (4.1 t; 4.5 short tons) Water cap. 2,000 imp gal (9,100 L; 2,400 US gal) Firebox: ​  • Grate area 23 sq ft (2.1 m2) Boiler 4 ft 9 in (1.45 m) Boiler pressure 175 psi (1.21 MPa) Heating surface: ​  • Firebox 124 sq ft (11.5 m2)  • Tubes 680 sq ft (63 m2)  • Flues 280.6 sq ft (26.07 m2)  • Total surface 1,084.6 sq ft (100.76 m2) Superheater: ​  • Heating area 191.134 sq ft (17.757 m2) Cylinders 3 Cylinder size 16+1⁄2 in × 26 in (419 mm × 660 mm) Valve gear Stephenson
Performance figures Tractive effort 22,940 lbf (102.0 kN)
Career Operators London and North Eastern Railway, British Railways Withdrawn 1957–1960 Disposition All scrapped

Overview

In 1931, H1 No. 2162 was rebuilt as a 4-6-2T and given the A8 classification. After a series of trials throughout the North East Area, all of the remaining H1s were rebuilt as A8 4-6-2Ts between 1933 and 1936. During the process of rebuilding, the boiler was modified to include a Robinson-type superheater rather than the original Schmidt superheater. In 1935, further modifications resulted in the A8 boiler being interchangeable with the A6, A7, A8, H1, and T1 classes.

Service

The rebuilt A8s could easily work the heavy suburban traffic and long distance coastal trains on which they were put to work. They were also welcome replacements for the ageing G5 0-4-4Ts which had been working these services. Allocations of the 45 locomotives were split between the North East / Newcastle area, the Yorkshire Coast Whitby and Scarborough, Hull, and Leeds (Neville Hill).

Technical details

• Weight: 86 long tons 18 cwt (194,700 lb or 88.3 t)
• Boiler pressure: 175 lbf/in² (1.21 MPa), superheated
• Cylinders: three, 16.5 by 26 in (419 by 660 mm)
• Driving wheels: 5 ft 9 in (1.753 m)
• Tractive effort: 22,940 lbf (102.0 kN)
• Number sequence in (1957/57) was from 69850 to 69894 (previously 9850 to 9894).

Withdrawal

Diesel railcars were rapidly introduced during the 1950s, and the A8s quickly became surplus to requirements. Withdrawals started in 1957, and the A8 was extinct by the end of 1960.

References

• Yeadon, Willie (2001). Yeadon's Register of LNER Locomotives. Vol. 21: Class A5 to A8, H1, H2, L1(L3), L2, M1 and M2 tank engines. Booklaw/Railbus.

External links

• The Raven/Gresley A8 Pacific Tank Locomotives LNER Encyclopedia