Caledonian Railway 49 and 903 Classes

Caledonian Railway 49 Class [903 Class]

903 Cardean
Type and origin
Power type Steam
Designer John F. McIntosh
Builder St. Rollox Works
Build date
  • 49: 1903
  • 903: 1906
Total produced
  • 49: 2
  • 903: 5
Specifications
Configuration 4-6-0
UIC class 2′C n2
Gauge 4 ft 8 12 in (1,435 mm)
Driver dia. 6 ft 6 in (1.98 m)[1]
Loco weight 70 tons [73 tons] when built,
71.5 tons [74.25 tons] as rebuilt[1]
Tender weight 55 tons [57 tons][1]
Boiler pressure 200 psi when built, 175 psi as rebuilt[1]
Superheater Schmidt (as rebuilt)[2]
Cylinders Two, inside
Cylinder size New: 21 in × 26 in (533 mm × 660 mm) [20 in × 26 in (508 mm × 660 mm)]
Rebuilt: 20.75 in × 26 in (527 mm × 660 mm)[1]
Valve gear Stephenson
Performance figures
Tractive effort 25,000 lbf (110 kN) [22,700 lbf (101 kN)] when built, 21,300 lbf (95 kN) as rebuilt[1]
Career
Operators
Class CR: 49 and 903 classes
Power class LMS: 4P
Numbers
  • CR: 49–50, 903–907
  • LMS: 14750–14755
Withdrawn
  • 49: 1933
  • 903: 1915–1930
Disposition All scrapped

The Caledonian Railway 49 Class and 903 Class were 4-6-0 express passenger locomotives designed by John F. McIntosh and built at the Caledonian Railway's own St. Rollox Works in 1903 and 1906 respectively.

49 Class

Locomotive no. 49 in 1903

In 1903, the Caledonian Railway had no passenger locomotives larger than 4-4-0s, and the heaviest trains over its main line between Glasgow and Carlisle required to be double headed, even in the less demanding southbound ('up') direction. Northbound ('down') trains also required banking assistance on the climb to Beattock Summit. In an effort to avoid these requirements, McIntosh designed a large 4-6-0 based on his 'Dunalastair' series of 4-4-0s. Two locomotives were built in 1903, and immediately became the Caledonian's flagship locomotives. Nonetheless, their performance did not live up to expectations, and it was soon clear that banking assistance was still required over Beattock.[3] Until 1906 the Caledonian railway had no turntables long enough for the 49 Class, and arrangements for turning them included use of the Cathcart Circle or turning locomotive and tender separately.[4]

903 Class

By 1906, experience with the 49 Class had enabled McIntosh to design an improved version, and the installation of new turntables at major engine sheds presaged the arrival of five new locomotives. The first of these, number 903, was named "Cardean" after the country estate of one of the CR directors, and immediately became the company's new flagship locomotive, with its name becoming a nickname for the whole class. The Caledonian gave the new locomotives a great deal of publicity and "Cardean" thus achieved some fame. Even so, the performance of the 903s was still unremarkable.[5]

Rebuilding and subsequent service

Neither class was equipped with superheating when built, but all seven locomotives were rebuilt with Schmidt superheaters and new cylinders during 1911. These modifications reduced coal consumption but made little difference to the locomotives' performance,[2] and McIntosh built no more large passenger 4-6-0s (although he did build smaller 4-6-0s for goods traffic). His successor William Pickersgill had no greater success with his sluggish outside-cylindered 60 Class or the disastrous three-cylinder 956 Class, so the Caledonian Railway continued to rely heavily upon 4-4-0s for express passenger traffic until the Grouping.

One 903 class locomotive was withdrawn in 1915 due to accident damage, but the other six locomotives passed to the London, Midland and Scottish Railway in 1923. The two 49 class locomotives were extensively renewed around 1924 with new frames and cylinders,[6] but all of the Caledonian passenger 4-6-0s were quickly eclipsed by new LMS Compound 4-4-0 and Royal Scot 4-6-0s. The four surviving 903s were withdrawn in 1927–30, whilst the two 49s lasted until 1933. All were scrapped.

Accidents and incidents

Numbering and locomotive histories

Table of locomotives[8]
CR no. CR name LMS no. Delivered Works Withdrawn Class
49 14750 March 1903 St. Rollox March 1933 49 Class
50 Sir James Thompson 14751 April 1903 St. Rollox December 1933 49 Class
903 Cardean 14752 May 1906 St. Rollox December 1930 903 Class
904 14753 June 1906 St. Rollox May 1929 903 Class
905 14754 June 1906 St. Rollox September 1927 903 Class
906 14755 June 1906 St. Rollox February 1928 903 Class
907 July 1906 St. Rollox May 1915 903 Class

References

  1. 1 2 3 4 5 6 Atkins 1987, pp. 98–101.
  2. 1 2 Atkins 1976, p. 43.
  3. Atkins 1976, p. 38.
  4. Atkins 1976, p. 39.
  5. Essery & Jenkinson 1986, p. 35.
  6. 1 2 Atkins 1976, p. 44.
  7. 1 2 Earnshaw 1990, p. 10.
  8. "BritishSteam locomotive information". BritishSteam.com. Retrieved 2013-05-26.


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