LMS Ivatt 2MT (Class 2 Mogul)

Henry George Ivatt was the son of Henry Alfred Ivatt, the Great Northern Railway's locomotive engineer, and was appointed chief mechanical engineer of the LMS in 1946 on the death of Charles Fairburn. Ivatt found himself with a brief to design a new generation of light branch-line tank and tender engines that would replace the great mass of pre-Grouping engines still in service on the LMS's rural lines. He had a particular interest in shed-friendly design: locomotives that could be cleaned, fired, and serviced with the minimum of labour, at a time when post-war labour shortages were forcing British railways to think hard about the cost of running steam.

The 2MT mogul, introduced in 1946, embodied that thinking. It was a small mixed-traffic 2-6-0 with outside cylinders (so motion was easy to inspect at sheds), a self-cleaning smokebox, a rocking grate, and a self-emptying ashpan. The overall design was deliberately simple, with two cylinders, Walschaerts valve gear, and a tapered Type 3B boiler that was carried over from the related Ivatt 4MT mogul (which itself was a development of an earlier Stanier project). The first batch of 20 engines was built at Crewe Works in 1946 and 1947 with double chimneys for evaluation; subsequent production reverted to single chimneys, and the double chimneys were eventually removed from the early engines.

128 were built between 1946 and 1953 at Crewe (most) and Darlington Works. The class was so successful that it was effectively re-issued as the BR Standard Class 2 mogul (78000 to 78064) of 1952 to 1956, which was almost identical apart from minor BR-style fittings. The Ivatt 2MT and the BR Standard Class 2 between them produced a fleet of around 193 engines that was the standard light mixed-traffic mogul of the British Railways era.

The Ivatt 2MTs spent their working lives on branch and secondary services across the British Railways system. They were a familiar sight on the rural Welsh cross-country lines, the Stratford and Midland Junction Railway, the Great Central's Nottingham-to-Sheffield section, the Yorkshire and Lincolnshire branches, the Highland Region's lighter routes, and the Border Counties services in Scotland. They handled stopping passenger trains of three or four coaches, summer Saturday relief turns to seaside termini, parcels, milk, and pick-up freight.

The class was popular with crews for being free-running, easy to fire, and unfussy in service. Maintenance staff appreciated the ease of the outside cylinders, the self-cleaning smokebox, and the rocking grate, all of which materially reduced the labour required at end-of-shift servicing.

Withdrawals began in the early 1960s as branch lines closed under the Beeching Plan and as diesel multiple units replaced steam-hauled stopping trains. The class was decimated between 1963 and 1967, by which time the surviving Ivatt 2MTs had been concentrated on a small number of secondary lines (including the Cambrian Coast, the East Suffolk, and the Highland Region's Aberdeen-to-Inverness route). The last Ivatt 2MT moguls were withdrawn from BR service in 1967.

46428 entered traffic in 1953 and worked the Stoke and Crewe areas before being withdrawn in 1966. Saved from Barry in 1976, it has worked at the East Lancashire Railway and several other heritage railways and is currently in working order.

46443 was completed in 1950 and spent its working life on the Western and LM regions. Withdrawn in 1967, it was preserved by the Severn Valley Railway directly from BR service and is one of the most reliably-maintained Ivatt 2MTs in preservation, having been a regular performer on the SVR for over fifty years.

46447 entered traffic in 1950 and worked rural Welsh and Border services. Saved from Barry in 1976 and now operating at the Strathspey Railway in Scotland.

46512 entered traffic in 1952 and is currently based at the Strathspey Railway, where it has been in regular service.

46521 entered service in 1953 and worked from Bedford and Bletchley. Now preserved at the Great Central Railway.

46464 entered traffic in 1950 and is currently based at the Strathspey Railway in Aviemore.

Six other Ivatt 2MT moguls (and the very similar BR Standard Class 2 78xxx 2-6-0 derivatives) survived in various preservation locations.

The first 12 engines (1946 to 1947) were turned out in plain LMS black with smokebox-side number plates. The post-1948 production was painted in BR mixed-traffic lined black with the early lion-and-wheel emblem; from 1956 the late ferret-and-dartboard crest was applied at general overhauls. A small number of preserved examples have been turned out in LMS lined black with the LMS crest as a tribute to the original 1946 prototype, and several have appeared in BR mixed-traffic lined black with both early and late crests during their preservation careers.