LMS Fowler 2-6-4T

The London, Midland and Scottish Railway (LMS) Fowler 2-6-4T was a class of steam locomotive passenger tank engine designed by Henry Fowler.

Construction
125 examples of the class were built. The last 30 numbered 2395 to 2424 were fitted with side-windows and doors to their cabs. The LMS classified them 4P, BR 4MT. They were the basis for a family of subsequent LMS/BR Class 4 2-6-4T locomotives. The Irish Northern Counties Committee (NCC) Class W 2-6-0 moguls were also strongly influenced by this class, albeit the driving wheel diameter was three inches greater to match the NCC practice.

The cylinder and piston valve design and the setting of the Walschaerts valve gear, allowing a maximum travel of 6+3/8 in in full gear, was believed by O. S. Nock to subsequently lead to the "outstanding success" of the class.

Operational use
Most of the class were used on longer-distance commuter trains from stations in London, Manchester and other large towns. A number were allocated to Tebay Motive Power Depot and were used to bank heavy passenger and goods trains up the steep incline to Shap on the LMS West Coast Main Line. Some operated on the long trip from Shrewsbury to Swansea (Victoria). The last two surviving locos were withdrawn from service in 1966. 42389 was hauling the Tring to Euston commuter train that was hit in the rear at Harrow and Wealdstone on 8 October 1952 by a Perth to Euston express. 112 people died in the accident. 42389 was undamaged.

Despite coupled wheels of only 5 ft diameter the class was sometimes noted as achieving over 80 mph on outer suburban services to and from Euston.

Numbering
The LMS numbered the class 2300–2424, BR adding 40000 to their numbers to make them 42300–424.

Preservation and revival
No locos were preserved, but the January 2013 edition of The Railway Magazine reported that a new-build project to recreate a Fowler 2-6-4T was at an initial research stage.

In May 2015, the LMS-Patriot Project announced that after the completion of Patriot Class No. 45551 The Unknown Warrior, it would begin construction on a new-build Fowler 2-6-4T. Similar to the Patriot, it will carry the number of the last member of the class, No. 42424, and be built to main line running standards, though it will only primarily be used on heritage lines.

One of the NCC Class WT locos (No. 4), which drew heavily from the Fowler design and were the last steam locomotives withdrawn in Northern Ireland, is preserved by the Railway Preservation Society of Ireland. No. 4 returned from overhaul in June 2015 and is currently based in Dublin.