GER Class M15

GER Class M15 and M15R LNER/BR Class F4 and F5
No. 67200 at Ongar Station, March 1957
Type and origin Power type Steam Designer F4, Thomas William Worsdell F5, James Holden Builder Stratford Works Build date F4 built 1884-1909 F5 rebuilt 1911-1920 Total produced 160
Specifications Configuration: ​  • Whyte 2-4-2T Gauge 4 ft 8+1⁄2 in (1,435 mm) Driver dia. 5 ft 4 in (1.626 m) Loco weight 53 long tons 19 cwt (120,800 lb or 54.8 t) Fuel type Coal Boiler pressure F4, 160 psi (1.10 MPa) F5, 180 psi (1.24 MPa) Cylinders Two, inside Cylinder size 17.5 in × 24 in (440 mm × 610 mm) Valve gear F4, Joy valve gear F5, Stephenson valve gear
Performance figures Tractive effort F4, 15,618 lbf (69.47 kN) F5, 17,571 lbf (78.16 kN)
Career Operators GER » LNER Class GER: M15 and M15R LNER: F4 and F5 Nicknames Gobblers Withdrawn 1955–1958 Disposition All original locomotives scrapped; one new-build under construction

The GER Class M15 was a class of 160 2-4-2T steam locomotives designed by Thomas William Worsdell and built for the Great Eastern Railway between 1884 and 1909. The original (F4) class of locomotives were fitted with Joy valve gear which was notoriously difficult to 'set'. This earned them the nickname of 'Gobblers' thanks to their high coal consumption rates. As a result, between 1911 and 1920, 30 of them were rebuilt by James Holden with Stephenson valve gear and higher pressure boilers. Despite this, the nickname stuck for many years after.

Rebuilding

Rebuilding included the fitting of a higher pressure boiler, and also involved replacing Joy valve gear with Stephenson valve gear thus forming the M15R class.

Modifications

Many were fitted with condensing gear for working in the London area and a few were fitted with push-pull apparatus for working trains on the route to Ongar station.

Ownership

London and North Eastern Railway

They all passed to the London and North Eastern Railway (LNER) at the 1923 grouping and received the following classifications:

• Unrebuilt locomotives, F4
• Rebuilt locomotives, F5.

British Railways

Some of the F4s and all of the F5s passed into British Railways (BR) ownership in 1948 and their BR numbers were:

• Class F4, 67151-67187
• Class F5, 67188-67217

Preservation

None of the F5s or F4s survived into preservation, however a project to build a new F5 was launched in the early 2000s and as of January 2014 has progressed well. So far the main frames, smokebox, cab/bunker platework and lots of smaller components have been acquired/manufactured. The project is partway through a move to Tyseley Locomotive Works for erection and construction work to continue following a long period at Mangapps Railway Museum. The completed locomotive (originally set to appear as 67218 in BR Black) is to be outshopped as No.789 in Great Eastern Railway blue livery.