LMS Princess Royal Class

The London, Midland and Scottish Railway (LMS) Princess Royal Class is a class of express passenger 4-6-2 steam locomotive designed by William Stanier. Twelve examples were built at Crewe Works, between 1933 and 1935, for use on the West Coast Main Line. Two are preserved.

Princess Royal Class
6210 Lady Patricia at Crewe Works in 1948
Type and origin
Power typeSteam
DesignerWilliam Stanier
BuilderLMS Crewe Works
Build date1933 (2), 1935 (10)
Total produced12
Specifications
Configuration:
​
 • Whyte4-6-2
 • UIC2′C1′ h4s
Gauge4 ft 8+1⁄2 in (1,435 mm)
Leading dia.3 ft 0 in (0.914 m)
Driver dia.6 ft 6 in (1.981 m)
Trailing dia.3 ft 9 in (1.143 m)
Minimum curve
  • 6 chains (121 m) normal
  • 4+1⁄2 chains (91 m) dead slow
Wheelbase63 ft 10 in (19.456 m)
 • Engine37 ft 9 in (11.506 m)
 • Drivers15 ft 3 in (4.648 m)
 • Tender15 ft 0 in (4.572 m)
Length74 ft 4+1⁄4 in (22.663 m)
Width9 ft 0 in (2.743 m)
Height13 ft 3 in (4.039 m)
Axle load22.5 long tons (22.9 t)
 • Leading21 long tons (21 t)
 • Coupled22 long tons (22 t)
 • Trailing16 long tons (16 t)
 • Tender axle
  • Front: 18.6 long tons (18.9 t)
  • Middle: 17.8 long tons (18.1 t)
  • Rear: 18.25 long tons (18.54 t)
Adhesive weight67.5 long tons (68.6 t)
Loco weight
  • 104.5 long tons (117.0 short tons; 106.2 t)
  • 46202: 110.55 long tons (123.82 short tons; 112.32 t)
Tender weight54.65 long tons (61.21 short tons; 55.53 t)
Fuel typeCoal
Fuel capacity
  • 9 long tons (10 short tons; 9.1 t)
  • later 10 long tons (11 short tons; 10 t)
Water cap.4,000 imp gal (18,000 L; 4,800 US gal)
Firebox type 
 • Firegrate area45 sq ft (4.2 m2)
Boiler:
​
 • ModelLMS type 1
 • Tube plates19 ft 3 in (5.867 m)
 • Small tubes2+3⁄8 in (60 mm), 32 off
 • Large tubes5+1⁄8 in (130 mm), 123 off
Boiler pressure250 psi (1.7 MPa)
Heating surface 
 • Tubes and flues2,299 sq ft (213.6 m2)
 • Firebox190 or 217 sq ft (17.7 or 20.2 m2)
Superheater:
​
 • Heating area584 sq ft (54.3 m2)
Cylinders4
Cylinder sizeProduction Models:
16+1⁄4 in × 28 in (413 mm × 711 mm)
Valve gearWalschaerts
6205 had outside Walschaerts with rocking shafts operating inside valves.
Valve typePiston valves
Performance figures
Tractive effort40,286 lbf (179.20 kN) (production engines)
Career
Operators
Power class7P reclassified 8P in 1951
Numbers(4)6200/1/3–12
NicknamesLizzies
LocaleLondon Midland Region
Withdrawn1961 (6), 1962 (6)
Preserved6201, 6203
DispositionTwo preserved, remainder scrapped

Overview

The designer of the class, William Stanier, had previously been Works Manager of the Great Western Railway's depot at Swindon Works, and had been recruited with a brief to replace the LMS's miscellany of locomotives inherited from its constituent companies. He nade extensive use of Great Western features in his designs.

To match the power and speed and especially the prestige of the London and North Eastern Railway's express Pacific locomotives, Stanier designed the Princess Royal class almost as soon as he was appointed to the LMS. When originally built, they were used to haul the famous Royal Scot train between London Euston and Glasgow Central.

Design

The class was based on GWR 111 The Great Bear, a design produced in 1907 for the Great Western by George Jackson Churchward.[1] The smokebox and cylinders were closely based on those of the GWR 6000 Class (also known as the King Class).[2] The inside cylinders were abreast the leading bogied wheels and drove cranks on the leading coupled axle, the outside cylinders were abreast the rear bogie wheels (which made substantial cross bracing necessary to brace the cylinders and the locomotive frame together) and drove crank pins on the centre coupled axle.[3] Each of the four cylinders had its own set of Walschaerts valve gear.

Other minor details, such as corks to close oil boxes, closely followed Great Western practice.

Construction

A prototype batch of three locomotives was to be constructed in 1933. Two were constructed as drawn but the third set of frames was retained as the basis for an experimental turbine locomotive.[4][5][6]

Turbomotive
Main article: LMS Turbomotive

The third prototype was constructed with the aid of the Swedish Ljungstrom turbine company and known as the Turbomotive, although not named. It was numbered 6202, in sequence with the Princess Royals. Although 'generally similar' to the rest of the Princess Royals,[4] and 'not all that much different',[7] it used a larger 40 element superheater to give a higher steam temperature, more suitable for turbine use.[5][8][note 1] This boiler was also domeless as would later be used for the second batch of the Princess Royals. The continuous exhaust of the turbine, rather than the sharper intermittent blast of the piston engine, also required changes to the draughting and the use of a double chimney.[9][10] It entered service in June 1935 on the London–Liverpool service.[11]

This Turbomotive was rebuilt in 1952 with conventional 'Coronation' cylinders and named Princess Anne, but was soon destroyed in the Harrow and Wealdstone rail crash.[10]

Later production

A second batch of eleven locomotives was constructed later.[12] The first two locomotives of the class to be produced had a firebox combustion volume too small for the grate area, and the subsequent locomotives had enlarged fireboxes.[2]

Accidents and incidents
Main article: 1948 Winsford railway accident
  • On 17 April 1948, a passenger train hauled by locomotive No. 6207 Princess Arthur of Connaught was halted after a passenger pulled the communication cord. It was then hit from behind by a postal train, which a signalman's error had allowed into the section, resulting in the deaths of 24 passengers.
  • Main article: Weedon rail crashes § 1951 rail crash
    On 21 September 1951, locomotive No. 46207 Princess Arthur of Connaught was hauling an express passenger train that was derailed at Weedon, Northamptonshire due to a defective front bogie on the locomotive. Fifteen people were killed and 35 were injured.
  • Main article: Harrow and Wealdstone rail crash
    On 8 October 1952, locomotive No. 46202 Princess Anne was one of the locomotives on the 8:00 a.m express from Euston to Liverpool and Manchester, along with LMS Jubilee Class No. 45637 Windward Islands. Princess Anne took serious damage in the crash, having the leading bogie torn off and main frames buckled, and was scrapped after being deemed uneconomic to repair it.

Naming

Each locomotive was named after a princess, the official name for the class was chosen because Mary, Princess Royal was the Colonel-in-Chief of the Royal Scots. However, the locomotives were known to railwaymen as "Lizzies", after the second example of the class, named for Princess Elizabeth, who later became Queen Elizabeth II. Later examples of 4-6-2 express passenger locomotive built by the LMS were of the related but larger, Coronation Class.

Withdrawal

The class was withdrawn in the early 1960s in line with British Railways' modernisation plan.

Details
LMS
No.		 BR
No.		 Name(s) Date
Built		 Date
Withdrawn		 Notes
6200 46200 The Princess Royal 27 July 1933 17 November 1962 Last to be withdrawn.
6201 46201 Princess Elizabeth 3 November 1933 20 October 1962 Preserved.
6203 46203 Princess Margaret Rose 1 July 1935 20 October 1962 Preserved. Owned by the Princess Royal Class Locomotive Trust.
6204 46204 Princess Louise 19 July 1935 7 October 1961
6205 46205 Princess Victoria 24 July 1935 25 November 1961 Fitted with modified valve gear in 1947. Converted back to normal in 1955.
6206 46206 Princess Marie Louise 1 August 1935 20 October 1962
6207 46207 Princess Arthur of Connaught 9 August 1935 25 November 1961 Appeared in the 1930s classic documentary film No. 6207; A Study in Steel which showed the production of the locomotive from molten steel to the finished product.
6208 46208 Princess Helena Victoria 16 August 1935 20 October 1962
6209 46209 Princess Beatrice 23 August 1935 29 September 1962
6210 46210 Lady Patricia 6 September 1935 7 October 1961
6211 46211 Queen Maud 18 September 1935 7 October 1961
6212 46212 Duchess of Kent 21 October 1935 7 October 1961

Preservation

Two examples, 6201 Princess Elizabeth and 6203 Princess Margaret Rose are preserved and both have operated on the mainline in preservation. They were named after the two children of Prince Albert, Duke of York (later King George VI), and his wife, Elizabeth, Duchess of York (later Queen Elizabeth, and after the king's death, Queen Elizabeth the Queen Mother). Princess Elizabeth Alexandra Mary (later Queen Elizabeth II) was seven years old in 1933 when her namesake was built, and Princess Margaret Rose was nearly five in July 1935 when her namesake was completed. At the time, they were third and fourth in line to the throne. 'Princess Margaret Rose' is owned by The Princess Royal Class Locomotive Trust and is on static display at the West Shed Museum, Midland Railway-Butterley, Ripley, Derbyshire.

Note: Loco numbers in bold mean their current number.

Number Name Built Withdrawn Service Life Livery Location Owners Status Mainline Certified Photograph Notes
LMS BR
6201 46201 Princess Elizabeth Nov 1933 Oct 1962 28 Years, 11 Months LMS Crimson Lake (on completion) Carnforth MPD 6201 Princess Elizabeth Society Under Overhaul [13] No, to be certified Withdrawn July/August 2021 due to cracked firebox.

Mainline Standard overhaul commenced in September 2023.[14]

6203 46203 Princess Margaret Rose Jul 1935 Oct 1962 27 Years, 3 Months BR Crimson Lake, Late Crest Butterley Princess Royal Class Locomotive Trust Static Display No Last ran in 1996.
  • 46201 Princess Elizabeth at Carlisle awaiting scrapping. The locomotive was later preserved.
    46201 Princess Elizabeth at Carlisle awaiting scrapping. The locomotive was later preserved.
  • Princess Margaret Rose at Swanwick West Shed in 2006.
    Princess Margaret Rose at Swanwick West Shed in 2006.

Media
  • 6201 at Langho on Whalley Bank – sound recording.

References
  1. This trifurcated superheater design was later used on the Duchess class.[5]
  1. Tuplin 1969, p. 106
  2. Tuplin 1969, p. 107
  3. Tuplin 1969, p. 85
  4. Nock, p. 114
  5. Cook, A.F. (1999). Raising Steam on the LMS. RCTS. pp. 126–127. ISBN 0-901115-85-1.
  6. Rowledge, J.W.P. (1987). "3: The Princess Royal Class – The First Two". The LMS Pacifics. David & Charles. pp. 24–35. ISBN 0-7153-8776-6.
  7. Fryer 1990, p. 165
  8. Rowledge, J.W.P. (1987). "4: The 'Turbomotive'". The LMS Pacifics. David & Charles. p. 47. ISBN 0-7153-8776-6.
  9. "9: Unconventional Locomotives 1929–1935". The British Steam Railway Locomotive. Vol. II: from 1925 to 1965. Ian Allan. 1966. pp. 112–117. ISBN 0-7110-0125-1.
  10. "18: Stanier's 'Turbomotive'". Experiments With Steam. Patrick Stephens Limited. 1990. pp. 163–171. ISBN 1-85260-269-4.
  11. Fryer 1990, p. 167
  12. Rowledge, J.W.P. (1987). "5: The Princess Royal Class – Modifications, and the 1935 Batch". The LMS Pacifics. David & Charles. pp. 44–51. ISBN 0-7153-8776-6.
  13. Work Start's on Lizzie's Overhaul Trackside issue 27 October 2023 page 6
  14. Work Start's on Lizzie's Overhaul Trackside issue 27 October 2023 page 6
  • Ian Sixsmith The Book of the Princess Royal Pacifics ISBN 1-903266-02-5
  • Hugh Longworth British Railway Steam Locomotives 1948–1968 ISBN 0-86093-593-0
  • Rowledge, J.W.P. (1975). Engines of the LMS, built 1923–51. Oxford: Oxford Publishing Company. ISBN 0-902888-59-5.
  • David Hunt, Bob Essery and Fred James LMS Locomotive Profiles No. 4: The "Princess Royal" Pacifics
  • Tuplin, W.A. (1969). British Steam since 1900. London: Pan Books. ISBN 0-330-02721-2.
Wikimedia Commons has media related to LMS Princess Royal Class.
This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.