The Worsdell Class D18 (NER Q1) 4-4-0 Locomotives

D18 NER No. 1869 (M.Peirson)

There had been a series of 'races' between the East and West Coast routes to Scotland in 1888 and 1895. In the event of further races, the North Eastern Railway (NER) wished to be prepared and built the two Q1 (LNER D18) locomotives in 1896. Based on Wilson Worsdell's Class Q (LNER D17/2) locomotives, the Q1s were fitted with large 7ft 7.25in diameter driving wheels. These were be the largest coupled driving wheels fitted to any British locomotive, and were a clear indication of the Class Q1's purpose. Unfortunately the races never resumed, and no attempt was ever made to determine the Q1's top speed.

Based on the Class Q, the Class Q1 was actually built at the same time as the first batch of Class Q engines in 1896. Both types had an unusual clerestory roof. Due to the large wheels on the Q1s, the cab windows were positioned higher than usual. As well as the larger wheels, the Q1s were fitted with longer fireboxes resulting in 1sq. ft. extra firegrate area.

The D18 boilers were non-standard, and it was natural that they would be replaced with standard D17/2 boilers when they wore out. No. 1869 had its boiler replaced in August 1910, and No. 1870 had its replaced in September 1911. The D18s also saw similar modifications as the D17s. Schmidt superheaters were fitted to No. 1869 in March 1920, and No. 1870 in March 1915. No. 1869 received 19in diameter cylinders and piston valves at the same time as receiving a superheater, but No. 1870 kept its 20in cylinders until withdrawal. No. 1870 received piston valves in September 1911.

The D18s were initially allocated to Gateshead shed, and they were used on the East Coast main line services to Edinburgh and York. The services to York were preferred due to this route's relative lack of gradients, which suited the D18s. During this time, No. 1869 was recorded running the 44.25 miles from Darlington to York in 42 minutes 7 seconds with a load of 200 tons in heavy rain. This was an average speed of 61.7 mph, with a maximum speed of 74mph at Tollerton. After 1902 the NER's advertising claimed that it was running the fastest train in the British Empire (Newcastle to Bristol with a 43 minute schedule from Darlington to York). However, these racing locomotives were rarely used on it, with preference being given to the more powerful D20s which had been introduced.

The D18s were soon transferred to Neville Hill, where they worked services to Hull, York, and Scarborough. They were also seen on services to Stockton and West Hartlepool via the Harrogate and Northallerton route. This is of particular note because the route through Harrogate is notably hilly for a locomotive with such large driving wheels. Both D18s were withdrawn in October 1930. During their final decade, the D18s proved to be competent performers with loads of up to six coaches.

Technical Details

The following details for No. 1869. No. 1870 had larger 20in diameter cylinders, and a corresponding tractive effort of 15,500lb.

Cylinders (x2): (inside) 19x26in.
Motion: Stephenson
Valves: 8.75in piston
Boiler: Max. Diameter: 4ft 4in
Pressure: 160psi
Diagram No.: 65
Heating Surface: Total: 1097 sq.ft.
Firebox: 123 sq.ft.
Superheater: 204 sq.ft. (18x 1.1")
Tubes: 479 sq.ft. (89x 1.75in)
Flues: 291 sq.ft. (18x 5.25in)
Grate Area: 19.8 sq.ft.
Wheels: Leading: 3ft 7.25in
Coupled: 7ft 7.25in
Tender: 3ft 9.25in
Tractive Effort: (@ 85% boiler pressure) 13,990lb
Wheelbase: Total: 46ft 2.75in
Engine: 23ft 9in
Tender: 12ft 8in
Weight (full): Total: 94 tons 14cwt
Engine: 53 tons 10cwt
Tender: 41 tons 4cwt
Max. Axle Load: 19 tons 4cwt

Preservation

None of the D18s survived into preservation.

Models

I am not aware of any models of the D18s in any scale.

Acknowledgements

Thank you Malcolm Peirson for the photograph of No. 1869.