LMS Princess Coronation Class

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Preserved 6233 Duchess of Sutherland running in 2001. She is roughly in the same condition as between 1941 (when a double chimney was fitted) and 1945 (when she received her smoke deflectors), though it is unlikely that she ever would have carried a nameplate that read www.prlt.co.uk!

6233 Duchess of Sutherland with smoke deflectors. The crowns were added when 6233 hauled the Royal Train to mark Queen Elizabeth II's Golden Jubilee.

46229 Duchess of Hamilton was originally built as streamlined. As of 2005 there is an ongoing appeal to restreamline her.

Unstreamlined 46234 Duchess of Abercorn at Crewe during the British Railways era.

Unstreamlined 46232 Duchess of Montrose at Crewe having recently emerged from the paint shops.

Semi-streamlined 46241 City of Edinburgh at Stafford, 1954. The sloping smokebox front can be made out.

46229 in Semi-streamlined condition at Tyseley, 6 May 2006.

The Princess Coronation Class is a class of express passenger steam locomotives built by the London Midland and Scottish Railway (LMS) and designed by William Stanier. They were an enlarged version of the LMS Princess Royal Class. Several examples were originally built as streamlined, though this was later removed. The non-streamlined locomotives were often referred to as the "Duchess Class". To enginemen they were all known as Big Lizzies.

[edit] Overview

The first five, 6220-4, were built in 1937. They were streamlined and painted Caledonian Railway blue with silver horizontal lines to match the Coronation Scot train they were built to haul. The streamlining is probably best described as like an upside down bathtub and was largely for publicity reasons. The second five, 6225-9, were also streamlined, but painted in the more traditional crimson lake, with gilt horizontal lining. This was to match new stock that included articulated coaches. The next batch was built un-streamlined. They were considered to be very handsome locomotives. Smoke deflectors were added from 1945 due to drifting smoke obscuring the crew’s forward vision. War interrupted the building of the locomotives, but given the dire shortage of express motive power several more were then finished during the war and turned out in unlined black. 6253-57 were turned out in the 1946 LMS lined black and 46257 was turned out in BR black. Two locomotives to a modified design by George Ivatt were built in 1947 (6256) and 1948 (46257).

Single chimneys were fitted to 6220-6234 when built but they were replaced with double chimneys between 1939 and 1944. 6235 onwards were built with double chimneys. Smoke deflectors were fitted from 1945 with the last 5 carrying them from new.

An unusual feature of the tenders was that they were fitted with a steam-operated coal pusher to bring the coal down to the firing plate. When this was in operation a plume of steam could be seen rising from the rear face of the coal bunker backwall.

[edit] De-Streamlined Locomotives

The streamlining was removed from the fitted locomotives from 1946 onwards. It had been found to be a little value at speeds below 90mph, and was unpopular with running shed staff. Only 3 were still fitted at the end of the LMS period and they had been stripped by the end of 1949. Only 46243 City of Lancaster carried its British Railways number whilst streamlined.

Initially de-streamlined locomotives could readily be recognised by the sloping top to the smokebox. All were eventually replaced with fully round smokeboxes. The sloping top led to the train-spotters nickname of Semis (i.e. semi-streamlined).

[edit] Liveries

The livery history for these locomotives involves no less than 11 variations.

LMS Streamliner – Blue, Red, Wartime Black

LMS Non-streamliner – Red, Wartime Black, 1946 Black

BR Experimental – Blue, Black

BR Standard – Blue, Green, Red

Only 16 locomotives were painted BR Red and these were allocated to the London Midland Region, Scottish allocated locomotives remained Green.

[edit] Technical

Power Classification: 7P, reclassified 8P in 1951.

Introduced: 1937-1948

Designer: Sir William Stanier

Weights:

Loco: - 105t 5cwt (Conventional), 108t 2cwt (Streamlined), 106t 8cwt (Ivatt) .

Tender: 56t 7cwt

Driving Wheel: 6' 9"

Boiler pressure: 250psi superheated

Cylinders (4): 16 ½ " x 28"

Tractive Effort: 40,000lbf

Valve Gear: Outside Walschaert with rocking shafts (piston valves)

[edit] Details

[edit] Preservation

Three Duchesses have survived. (4)6229 Duchess of Hamilton, (4)6233 Duchess of Sutherland have both seen action on main line railtours. Duchess of Hamilton, now out of working order, is in the process of a Steam Railway appeal to have her restreamlined. The third, (4)6235 City of Birmingham was the centrepiece in the, now defunct, Birmingham science museum. 46235 was put in place and the museum built around her.

Following a successful appeal run by Steam Railway Magazine, 46229 is to be re-streamlined. The locomotive has been moved to the Birmingham Railway Museum at Tyseley, where the work is being carried out. The project will be completed by July 2007, when the locomotive will return to York for the 70th anniversary of the Coronation Scot service - taking her place at the heart of a new National Railway Museum temporary exhibition.

[edit] Sound

• 6233 Departing Kirkby Stephen
• 6233 Passing Selside

[edit] References

• David Jenkinson (1980) The Power of the Duchesses Oxford Publishing Company ISBN 0-86093-063-7
• Ian Sixsmith The Book of the Coronation Pacifics ISBN 1-871608-94-5
• Hugh Longworth British Railway Steam Locomotives 1948-1968 ISBN 0-86093-593-0

[edit] External links

• Princess Royal Locomotive Trust (owners of 6233)
• Thinktank, Birmingham science museum (6235 on display)
• Princess Coronations