NER Class S1 LNER Class B14
Type and origin Power type Steam Designer Wilson Worsdell Build date 1900-1901 Total produced 5
Specifications Configuration: ​  • Whyte 4-6-0 Leading dia. 3 ft 7+1⁄4 in (1.099 m) Driver dia. 6 ft 8+1⁄4 in (2.038 m) Wheelbase 27 ft 6 in (8.38 m) engine 12 ft 8 in (3.86 m) tender 51 ft 6+3⁄4 in (15.716 m) total Axle load 19.5 long tons (19.8 t) Loco weight 67.1 long tons (68.2 t) Tender weight 41.1 long tons (41.8 t) Total weight 108.2 long tons (109.9 t) 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 120 sq ft (11 m2)  • Tubes 935 sq ft (86.9 m2)  • Flues 401 sq ft (37.3 m2)  • Total surface 1,750 sq ft (163 m2) Superheater: ​  • Heating area 294 sq ft (27.3 m2) Cylinders 2 (outside) Cylinder size 20 in × 26 in (510 mm × 660 mm) Valve gear Stephenson
Performance figures Tractive effort 19,310 lbf (85.9 kN)
Career Operators North Eastern Railway, London & North Eastern Railway Numbers 2111-2115 Withdrawn 1929-1931 Disposition All scrapped

The NER Class S1 (LNER Class B14) was a class of 4-6-0 steam locomotives of the North Eastern Railway. It was designed by Wilson Worsdell and five locomotives were built between 1900 and 1901 at Gateshead works. The S1 was similar to the NER Class S but had larger driving wheels and a higher boiler pressure.^[1]

Schmidt superheaters and longer smokeboxes were fitted between 1913 and 1917.

When built, the S1s hauled heavy passenger expresses between York, Newcastle, and Edinburgh. They were gradually replaced on these services by NER Class R and NER Class R1 4-4-0s. From 1907, they were mainly used for hauling fish trains.

All five locomotives were withdrawn between 1929 and 1931 and none were preserved.