LMS Royal Scot Class

infobox Locomotive
name=LMS Royal Scot Class
powertype=steam
railroadclass=6P; reclassified 7P in 1951
builder=North British Locomotive Company (6100–6149)
London Midland & Scottish Railway, Derby works (6150–6169)
serialnumber = 23595–23644 (6100–6149)
builddate=1927, 1930
designer=Sir Henry Fowler
rebuilt: Sir William Stanier
weight=84 tons 18 cwt
cylindercount=3
cylindersize=18 in bore × 26 in stroke
boiler = G10¼S; rebuilt: 2A
boilerpressure=250 psi superheated
leadingdiameter = 3 ft 3½ in
wheeldiameter=6 ft 9 in
valvegear=Walschaert (piston valves)
tractiveeffort=33,150 lbf
gauge=RailGauge|ussg
whytetype=4-6-0
totalproduction=70

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caption = Parallel boilered 6100 "Royal Scot" poses for the official photograph after preparation for its North American tour, 1933.|The London, Midland and Scottish Railway (LMS) Royal Scot Class is a class of 4-6-0 express passenger locomotive introduced in 1927. Originally having parallel boilers, all members were later rebuilt with tapered type 2A boilers, and were in effect two classes.

Background

By the mid-1920s the LMS had followed the Midland Railway's small engine policy that meant that it had no locomotives of sufficient power for its expresses on the West Coast Main Line. Trains were entrusted to LMS/MR Midland Compounds 4-4-0s, the LNWR Claughton Class and the L&YR Dreadnought 4-6-0s. Construction of 50 of a new class of 4-6-0 was authorised from the North British Locomotive Works in Glasgow, and they were introduced without testing, the design being based on the SR Lord Nelson Class; although Radford claims that the boiler owed much to the MR 0-10-0 Lickey Banker 'Big Bertha'. A further 20 were built by Derby Works.

They were initially named after Regiments and some after historical LNWR locomotives, though those were renamed in 1935/6 to take more names of regiments.

From late 1931, after several bizarre forms were tried on various locomotives, the straight sided Smoke deflectors were added to stop drifting smoke; these were later replaced by angled-top items. From 1933 the class were taken off the top-link expresses, being superseded by the LMS Princess Royal Class and later the LMS Princess Coronation Class pacifics.

North American Tour

In 1933 one locomotive was sent to North America on a tour, 6152 swapping identities with 6100 "The Royal Scot", the identities never being swapped back after its return.

Fury

LMS 6399 Fury of 1929 was an unsuccessful experimental prototype locomotive based on the Royal Scot. It was rebuilt by William Stanier in 1935 to become 6170 "British Legion". This served as the blueprint for later rebuilding.

Rebuilding

In 1942 the LMS rebuilt two LMS Jubilee Class locomotives with type 2A boilers, but later turned to the Royal Scots. Most of these however turned out to be paper rebuilds - in effect new locomotives but rebuilding was more easily justified in the eyes of accountants. Initially these too were built without smoke deflectors but later acquired them.

Withdrawal

All were withdrawn between 1962 and 1965.

The class title of "Royal Scot" was subsequently re-used in 1976 as an official name for the then-new Class 87s but it never stuck, partly out of respect for the original fleet.

Details

Note: Built below refers to the 'LMS build date'.

Preservation

Two have been preserved. These are (4)6100 "Royal Scot" and (4)6115 "Scots Guardsman". No. 6100 Royal Scot is owned by Bressingham Steam Museum in Norfolk

In fiction

This class forms the basis for the Big City Engine in The Railway Series.

No. 6115 Scots Guardsman featured in the 1936 film Night Mail.

Models

Mainline produced No. 6100 "Royal Scot" as a 00 model. Bachmann took over the tooling for the locomotive, and produced it for some time, with the ultimate intention of re-tooling the design to incorporate their own higher level of detail, but unfortunately Hornby beat them to it, and produced their own Rebuilt Scots, these being introduced in 2007, along with the rebuilt patriot locomotives.Brassmasters do a limited edition kit in 4mm.

References

* David Jenkinson, "The Power of the Royal Scots" - OPC. (coffee table photo book).
* O. S. Nock "Royal Scots and Patriots of the LMS"
* Radford, "Derby Works and Midland Locomotives", - Ian Allan, 1971
* "The Book of the Royal Scots" - Irwell Press ISBN 1-871608-99-6