GNR Class N1 LNER Class N1[1]
Nos. 9459 and 9479 at Bradford Hammerton Street Depot in 1947
Type and origin Power type Steam Designer Henry Ivatt Builder Doncaster Works Build date 1906–1912 Total produced 56
Specifications Configuration: ​  • Whyte 0-6-2T  • UIC C1 n2t, eleven later C1 h2t Gauge 4 ft 8+1⁄2 in (1,435 mm) Driver dia. 5 ft 8 in (1.727 m) Trailing dia. 3 ft 8 in (1.118 m) Wheelbase First: 23 ft 3 in (7.09 m) Remainder: 23 ft 9 in (7.24 m) Length First: 35 ft 7+1⁄2 in (10.86 m) Remainder: 36 ft 7+1⁄2 in (11.16 m) Axle load 18.00 long tons (18.29 t) Adhesive weight First: 51.20 long tons (52.02 t) Remainder: 51.35 long tons (52.17 t) Loco weight First: 64.70 long tons (65.74 t) Remainder: 65.85 long tons (66.91 t) Fuel type Coal Fuel capacity 4.00 long tons (4.06 t) Water cap. 1,600 imp gal (7,300 L; 1,900 US gal) Firebox: ​  • Grate area 19 sq ft (1.8 m2) Boiler LNER diagram 7 Boiler pressure 170 psi (1.2 MPa) Cylinders Two, inside Cylinder size 18 in × 26 in (457 mm × 660 mm) Valve gear Stephenson Valve type Slide valves
Performance figures Tractive effort 17,900 lbf (79.62 kN)
Career Operators Great Northern Railway London and North Eastern Railway British Railways Class GNR/LNER: N1 Power class LNER: 2 BR: 2MT Numbers GNR: 190, 1551–1605 LNER: 3190, 4551–4605; 9430–9485 BR: 69430–69485 Axle load class LNER/BR: Route availability 5 Withdrawn 1947–1959 Disposition All scrapped

The Great Northern Railway (GNR) Class N1 was an 0-6-2T side tank steam locomotive designed by Henry Ivatt and introduced in 1906. They were all withdrawn from service between 1947 and 1959. None have survived.

Most of the class were fitted with condensing apparatus and worked in the London area, from King's Cross and Hornsey depots, on empty coach trains, and on cross-London exchange freight trains.

In 1914, Crewe Works built an armoured train which used a Class N1 engine. The engine was covered by a 14mm steel plate, and featured observation apertures to the front and side, closed by sliding steel shutters.^[2] Two of the Ivatt tank engines No. 1587 and No. 1590 were loaned to Crewe to be fitted with armor plating and were named HMT Norna and HMT Alice respectively. They were sold back to the LNER in 1923 and had their armor plating removed.^[3]