GWR locomotive numbering and classification

Last updated

The GWR was the longest-lived of the pre-nationalisation railway companies in Britain, surviving the 'Grouping' of the railways in 1923 almost unchanged. As a result, the history of its numbering and classification of locomotives is relatively complicated. This page explains the principal systems that were used.

Contents


Numbering

Broad Gauge Era

From the start, the GWR gave names only to its broad gauge locomotive stock. However, many classes carried 'themed' names, e.g. stars or signs of the zodiac, which aided identification of locomotives to some extent. See List of 7-foot gauge railway locomotive names

The exception to this rule was that any broad gauge locomotives the GWR absorbed from other railways (in particular, the South Devon Railway and Bristol and Exeter Railway) were given numbers in the 2000-2199 series. This applied even where locomotives had carried names under their previous owner (indeed, these names were usually removed by the GWR) and even when the locomotives had originally belonged to the GWR and had been sold out of stock.

Towards the end of the broad gauge era, a number of locomotives were built to a design that enabled them to be easily converted from one gauge to the other (hence the term 'convertibles' used for these locomotives). These engines also carried numbers in the standard gauge series, whether or not they were running in broad gauge form.

Standard Gauge 1854-1875

Initially standard gauge locomotive numbering was a simple sequential system, starting from 1. Numbering in this series, which included new locomotives and those absorbed from other railways, eventually reached 1297. New locomotives were identified as being paid from either revenue or capital account. Initially an effort was made to treat the numbering of locomotives bought out of revenue differently from those out of capital, including by re-using old numbers left vacant following withdrawal, using a duplicate number system (unusually, giving the new locomotives an A suffix - other railways tended to apply such notation to the old locomotive being replaced) and, for a few years, using the series 1000 (later 1001) upwards. In 1875, the sequential system starting at 1 reached 1000 and then jumped to 1116, the other side of the latter range of numbers still carried.

Standard Gauge 1875-1902

Under William Dean's leadership, blocks of numbers were allocated for different locomotive types, as follows:

NumbersTypes
1298 to 1400Absorbed standard and narrow gauge locomotives
1401 to 1500Passenger tank locomotives
1501 to 2000Goods tank locomotives
2001 to 2200Absorbed broad gauge locomotives (later reused for goods tank locomotives)
2201 to 3000Goods tender locomotives
3001 to 32004-2-2 express passenger locomotives
3201 to 35002-4-0 and 4-4-0 express passenger locomotives
3501 to 3600Passenger tank locomotives

The only exceptions to these principles under Dean were use of the 20xx, 21xx, and 27xx series for goods tank engines after the end of broad gauge operations. Experimental locomotives and other small classes continued to be numbered in gaps left following withdrawals in the number series below 1000.

Standard Gauge 1902-1912

Under George Jackson Churchward, the system applied by William Dean broke down, and new classes simply took the next free block of hundred numbers starting at xx01, with experimental engines numbered in odd gaps in the earlier series of numbers, usually below 110.

1912 Renumbering

In December 1912 (the official date being 28 December), the GWR undertook a renumbering of some of its locomotives — mainly 4-4-0 classes — so that locomotives of the same class were numbered consecutively. This desirable aim was made more important following the rebuilding of some Duke and Atbara locomotives to Bulldog and City class designs. A few of the changes were connected with a decision that blocks of numbers for each class should start at xx00 rather than xx01 as previously. [1]

4-4-0 classes
ClassOriginal NumbersNew Number RangeNotesRef
Atbara 3373-34124120-41483382 scrapped 1911;
3400-3409 rebuilt to City
[2]
Badminton 3292-33114100-4119 [3]
Bird 3731-37453441-3455 [4]
Bulldog (ex-Duke)Various (from 3253-3331)3300-3319 [5]
Bulldog (new build)3332-3372, 3413-3432, 3443-3472, 3701-37303320-3440 [6]
City (ex-Atbara)3400-34093700-3709 [7]
City (new build)3433-34423710-3719 [8]
County 3473-3482, 3801-38303800, 3831-38393801-3830 not renumbered [9]
Duke 3252-3291, 3312-3331 (various, total 40)3252-3291others rebuilt to Bulldog [10]
Flower 4101-41204149-4168 [11]
Other classes
ClassWheel arrangementOriginal NumbersNew Number RangeRef
455 (Metro) 2-4-0T 36003500 [12]
2600 (Aberdare) 2-6-0 332600 [13]
2721 0-6-0T 28002700 [14]
2800 2-8-0 972800 [15]
2900 (Saint) 4-6-0/4-4-2 98, 100, 171-1902998, 2900, 2971-2990 [16]
3100 2-6-2T 993100 [17]
3600 2-4-2T 113600 [18]
4000 (Star) 4-6-0 404000 [19]
4400 2-6-2T 115, 3101-104400-10 [20]
4500 2-6-2T 2161-904500-29 [21]
Cornwall Min. Rly 0-6-0T 14001398 [22]

Standard Gauge 1912 onwards

From the time of the 1912 renumbering, a system was adopted for new locomotives where the second digit indicated the broad type of locomotive. For example, express passenger locomotives had x0xx numbers and large mixed traffic tender locomotives were x9xx. When a class numbered more than 100 locos, rather than continue the numbers consecutively the second digit remained constant (e.g. 4900 Class included 4900-4999, 5900-5999, and 6900 onwards).

At the same time, a change was made so that new classes usually commenced from the number xx00. There was a certain amount of renumbering so that the prototype locomotives for existing classes took the appropriate xx00 number before the series used by production locomotives. Thus, from this time on, numbers below 2000 were mainly occupied by old, absorbed or otherwise non-standard locomotives.

For the separate numbering of steam rail motors, petrol and diesel railcars, diesel shunters and gas turbine locomotives, see section Other number series below.

1923 Renumbering

In 1923, the GWR absorbed a number of small railway companies as part of the Grouping. The locomotives that it inherited were renumbered into gaps in the number series below 2199 left vacant by the withdrawal of older locomotives. Many of these engines were withdrawn after a short period of time, but those that survived in 1946 were subject to another renumbering to rationalise the system further (see below).

The bulk of the locomotives absorbed were renumbered into gaps in broad number ranges according to their wheel arrangement. Locomotives from the following railways were included in this scheme: Alexandra Docks Railway, Barry Railway, Cambrian Railways, Cardiff Railway, Midland and South Western Junction Railway, Port Talbot Railway, Rhondda and Swansea Bay Railway, Rhymney Railway, South Wales Mineral Railway, Taff Vale Railway, Vale of Rheidol Railway, and Welshpool and Llanfair Light Railway.

Locomotives from the Brecon and Merthyr Railway, Burry Port and Gwendraeth Valley Railway and Neath and Brecon Railway were also renumbered according to their wheel arrangement, but used a different set of number ranges.

The number ranges used for all these locomotives are set out below, but note that those engines that had previously been sold out of stock by the GWR regained their original GWR numbers, and were not allocated new numbers in these ranges:

Wheel Arrangement Main Number RangeBMR, BPGVR and NBR Range
0-4-4T 2-23
2-6-0 24
4-4-4T 25-27
0-6-2T 30-60311-1375, 1668-1833
0-6-0T 604-8432161-2199
0-6-0 844-1013
4-4-0 1014-1128
4-4-0T 1129-11841392
2-4-0T 1189-11971400-1458
2-6-2T 1199-1213
4-4-2T 1301-13061391
2-4-2T 1307-1326
2-4-0 1328-1336
0-4-0T 1338-1343
0-6-4T 1344-1357
0-8-2T 1358-1386
0-8-0 1387-1390

The locomotives inherited by the GWR from other concerns were renumbered as follows:

1946 Renumbering

By 1946, the majority of the locomotives inherited at the 1923 Grouping had been withdrawn, as had most of the older GWR engines numbered below 2000. In order to tidy up the gaps in this number range, it was decided to renumber the surviving locomotives from each pre-Grouping company together. The series used were:

Oil burning locomotives

In 1946/7 a number of locomotives were converted to burn oil, and some were renumbered in the process. Eleven 4900 Hall Class locos were renumbered into the 3900 range. Twelve 2800 Class 2-8-0s and eight of the 2884 Class were renumbered into the 4800 range. To make way for these, the 4800 Class 0-4-2Ts were renumbered to the 1400 range. (In addition, five 4073 Castle Class and one 4300 Class 2-6-0 were converted, but not renumbered.) All engines were converted back to coal firing by 1950, and regained their original numbers. However, the 1400s were never renumbered back to 4800s. [23] [24]

Application by British Railways

When the GWR was nationalised as part of British Railways in 1948, its steam locomotives retained their numbers unchanged and new steam engines built to GWR designs continued to be allocated numbers in the same way as the GWR had done. However, its diesel locomotives were completely renumbered. They took numbers 15100-15107 in the 15xxx series allocated to pre-Nationalisation design diesel shunters.

Summary of post-1902 class numbering

GWR locomotive class numbering arranged by first and second digits
Legend
NN00-NN99Each section has a title showing the range of one hundred locomotive numbers it covers
If any locomotive classes used numbers in that range, there will be a section for each class, as follows
5700 First there is the number the class is known by (not necessarily in this range) linked to the appropriate article or article section
2161 ( > 4500) If the class was later renumbered away from this range, the later number range will be bracketed after the number following a > sign, and the section will be shaded pink
(4800 > ) 1400 If the class was renumbered into this range, the earlier number range will be bracketed before the number preceding a > sign, and the section will be shaded blue
4-6-0 County (1945)Next will come the wheel arrangement, with any name that the class (or sub-class) was known by
1901–1966Finally there is the date range during which any of the class was numbered in this range
x0x1x2x3x4x5x6x7x8x9
0x
0000–0099
0100–0199
  • 111
  • 4-6-2 The Great Bear
  • 1908–1924 [25]
0200–0299
0300–0399
0400–0499
0500–0599
0600–0699
0700–0799
0800–0899
0900–0999
1x
1000–1099
  • 1000
  • 4-6-0 County (1945)
  • 1945–1964 [26]
1100–1199
1200–1299
1300–1399
1400–1499
1500–1599
1600–1699
1700–1799
1800–1899
1900–1999
2x
2000–2099
2100–2199
2200–2299
  • 2221
  • 4-4-2T County Tank
  • 1905–1935 [34]
2300–2399
2400–2499
2500–2599
2600–2699
2700–2799
2800–2899
2900–2999
3x
3000–3099
3100–2199
3200–3299
3300–3399
3400–3499
3500–3599
  • 3571
  • 0-4-2T
  • 1895–1949
3600–3699
  • 3600
  • 2-4-2T 'Birdcage'
  • 1902–1934
3700–3799
3800–3899
3900–3999
4x
4000–4099
4100–4199
4200–4299
4300–4399
4400–4499
4500–4599
4600–4699
4700–4799
4800–4899
4900–4999
5x
5000–5099
5100–5199
5200–5299
5300–5399
5400–5499
5500–5599
5600–5699
5700–5799
5800–5899
5900–5999
6x
6000–6099
6100–6199
6200–6299
6300–6399
6400–6499
6500–6599
6600–6699
6700–6799
6800–6899
6900–6999
7x
7000–7099
7100–7199
7200–7299
7300–7399
7400–7499
7500–7599
7600–7699
7700–7799
7800–7899
7900–7999
8x
8000–8099
8100–8199
8200–8299
8300–8399
8400–8499
8500–8599
8600–8699
8700–8799
8800–8899
8900–8999
9x
9000–9099
9100–9199
9200–9299
9300–9399
9400–9499
9500–9599
9600–9699
9700–9799
9800–9899
9900–9999


Classification

A very simple system was adopted, whereby the name (for broad-gauge locomotives) or number of the first locomotive in a class became the classification for all locomotives in that class (e.g. 'Sun Class', '4000 Class'). After the end of the broad gauge, names were applied to principal passenger and mixed-traffic standard-gauge locomotives. These were often based on a single theme, which could also lend its name to describe a class, for example 'Stars', also known as the '4000 Class', whose names included 'North Star', 'Rising Star' etc.

However, the classes of locomotives inherited at the Grouping in 1923 continued to be referred to by the classification allocated to them by their original owner.


Other number series

In 1903, Churchward introduced the first steam rail motors, numbered 1 and 2. Construction continued until, by 1908, there were 99 consecutively-numbered rail motors in service. [108]

In 1911, a single petrol-electric railcar was built, and given the number 100. [109]

Collett experimented with a diesel railcar in 1933. Numbered 1, it was underpowered, but the results were sufficiently encouraging that further railcars with varying specifications followed, the fleet being numbered 1–38. [110] [111]

A number of diesel shunters were bought from 1933 on, and numbered 1, 2, and 501–507. These were renumbered to 15100–15107 by BR Western Region. [112]

The GWR ordered two gas turbine locomotives in 1946, but neither was delivered until the GWR had given way to BR Western Region, which numbered them 18000 and 18100. [113]


See also

Notes

  1. Ten 34xx Atbaras were rebuilt as 37xx City class engines.
  2. These started as 0-4-2T, then 0-4-4T!
  3. Eleven 4900 Class locomotives were temporarily renumbered into the 3900 range while they were converted to oil burning.
  4. Twelve 2800 Class locomotives were temporarily renumbered into the 4800 range while they were converted to oil burning.
  5. Eight 2884 Class locomotives were temporarily renumbered into the 4800 range while they were converted to oil burning.
  6. These locomotives were all renumbered into the 7300 range when their weight distribution was changed in 1956-59. [105]
  1. RCTS Part 1, p.14
  2. RCTS Part 7, pp. G33, G35-G36
  3. RCTS Part 7, pp. G29, G32
  4. RCTS Part 7, pp. G19, G26-G27
  5. RCTS Part 7, pp. G12, G16-17, G19, G23-G24
  6. RCTS Part 7, pp. G19, G24-G26
  7. RCTS Part 7, pp. G33, G35-G36, G38
  8. RCTS Part 7, pp. G36, G38
  9. RCTS Part 9, pp. J10, J11-J12
  10. RCTS Part 7, pp. G12, G16-17
  11. RCTS Part 7, pp. G33, G36
  12. RCTS Part 6, pp. F28, F37
  13. RCTS Part 7, pp. G40, G36
  14. RCTS Part 5, pp. E67, E71
  15. RCTS Part 9, pp. J19, J22-J23
  16. RCTS Part 8, pp. H22-H23
  17. RCTS Part 9, pp. J28, J30
  18. RCTS Part 6, pp. F38, F41
  19. RCTS Part 8, pp. H6, H7
  20. RCTS Part 9, pp. J44, J46
  21. RCTS Part 9, pp. J46, J49
  22. RCTS Part 3, pp. C73-C74, C76
  23. 1 2 3 4 Whitehurst (1973), p. 98.
  24. Haresnape (1978), p. 73.
  25. 1 2 Haresnape (1978), pp. 78–81.
  26. 1 2 Haresnape (1978), pp. 98–102.
  27. 1 2 3 Whitehurst (1973), p. 17.
  28. Haresnape (1976), pp. 104–105.
  29. Haresnape (1978), pp. 82–83.
  30. 1 2 3 Haresnape (1978), pp. 73–77.
  31. Haresnape (1978), pp. 108–111.
  32. Haresnape (1978), pp. 112–115.
  33. 1 2 3 4 Haresnape (1976), pp. 72–77.
  34. Haresnape (1976), pp. 60–63.
  35. 1 2 Haresnape (1978), pp. 62–65.
  36. Whitehurst (1973), pp. 23–24.
  37. Whitehurst (1973), p. 25.
  38. Whitehurst (1973), pp. 26–27.
  39. 1 2 3 Haresnape (1976), pp. 34–41.
  40. Whitehurst (1973), pp. 27–28.
  41. Whitehurst (1973), p. 28.
  42. Haresnape (1976), pp. 24–33.
  43. Whitehurst (1973), p. 29.
  44. 1 2 3 4 5 6 7 Haresnape (1976), pp. 42–53.
  45. 1 2 Holcroft (1957), p. 68.
  46. 1 2 Holcroft (1957), p. 155.
  47. Whitehurst (1973), p. 30.
  48. 1 2 Holcroft (1957), p. 73.
  49. Haresnape (1978).
  50. 1 2 Haresnape (1976), pp. 56–59.
  51. 1 2 3 Haresnape (1978), pp. 104–107.
  52. Whitehurst (1973), p. 32.
  53. 1 2 3 4 5 6 7 8 9 Haresnape (1978), pp. 52–61.
  54. Whitehurst (1973), pp. 32–33.
  55. Whitehurst (1973), pp. 33–34.
  56. Whitehurst (1973), p. 35.
  57. Haresnape (1976), pp. 102–103.
  58. Tyseley Shed (2015).
  59. Halls of Fame.
  60. Haresnape (1976), pp. 64–71.
  61. 1 2 3 Haresnape (1978), pp. 18–29.
  62. Whitehurst (1973), pp. 36–37.
  63. Haresnape (1978), pp. 42–53.
  64. 1 2 3 Haresnape (1976), pp. 82–85.
  65. Whitehurst (1973), pp. 38–39.
  66. 1 2 3 4 5 6 Haresnape (1976), pp. 86–93.
  67. 1 2 Whitehurst (1973), p. 39.
  68. Haresnape (1976), pp. 54–55.
  69. Whitehurst (1973), p. 40.
  70. Whitehurst (1973), pp. 40–41.
  71. Haresnape (1976), pp. 94–95.
  72. Whitehurst (1973), pp. 41–42.
  73. Haresnape (1976), pp. 96–99.
  74. 1 2 3 Haresnape (1978), pp. 30–37.
  75. Whitehurst (1973), pp. 42–44.
  76. Whitehurst (1973), pp. 44–46.
  77. Whitehurst (1973), pp. 46–47.
  78. Whitehurst (1973), p. 47.
  79. 1 2 Whitehurst (1973), p. 48.
  80. Whitehurst (1973), pp. 48–49.
  81. Haresnape (1978), pp. 66–68.
  82. Whitehurst (1973), p. 50.
  83. 1 2 Haresnape (1978), pp. 38–41.
  84. Whitehurst (1973), pp. 51–52.
  85. Whitehurst (1973), p. 53.
  86. Whitehurst (1973), pp. 53–55.
  87. Haresnape (1978), pp. 42–51.
  88. Whitehurst (1973), pp. 56–57.
  89. 1 2 Haresnape (1978), pp. 69–72.
  90. Whitehurst (1973), pp. 57–58.
  91. Whitehurst (1973), pp. 58–59.
  92. Whitehurst (1973), pp. 59–60.
  93. Haresnape (1978), pp. 84–87.
  94. Whitehurst (1973), pp. 62–63.
  95. 1 2 Haresnape (1978), pp. 93–97.
  96. Whitehurst (1973), pp. 63–64.
  97. Whitehurst (1973), p. 64.
  98. Whitehurst (1973), p. 66.
  99. Whitehurst (1973), pp. 66–67.
  100. Whitehurst (1973), pp. 67–68.
  101. Haresnape (1978), pp. 88–91.
  102. 1 2 Whitehurst (1973), p. 69.
  103. Whitehurst (1973), pp. 71–72.
  104. Whitehurst (1973), p. 72.
  105. Haresnape (1976), p. 93.
  106. Whitehurst (1973), pp. 74–75.
  107. Whitehurst (1973), pp. 75–76.
  108. Haresnape 1976, p. 101.
  109. Haresnape 1978, p. 116.
  110. Haresnape 1978, pp. 116–117.
  111. Whitehurst 1973, pp. 76–77.
  112. Whitehurst 1973, p. 76.
  113. Haresnape 1978, pp. 116, 118.

Related Research Articles

<span class="mw-page-title-main">Locomotives of the Great Western Railway</span> List of railway locomotives used by the Great Western Railway

The first Locomotives of the Great Western Railway (GWR) were specified by Isambard Kingdom Brunel but Daniel Gooch was soon appointed as the railway's Locomotive Superintendent. He designed several different 7 ft 14 in broad gauge types for the growing railway, such as the Firefly and later Iron Duke Class 2-2-2s. In 1864 Gooch was succeeded by Joseph Armstrong who brought his standard gauge experience to the workshops at Swindon. To replace some of the earlier locomotives, he put broad gauge wheels on his standard gauge locomotives and from this time on all locomotives were given numbers, including the broad gauge ones that had previously carried just names.

<span class="mw-page-title-main">GWR 3300 Class</span>

The Bulldog and Bird classes were double-framed inside cylinder 4-4-0 steam locomotives used for passenger services on the Great Western Railway. The Bird Class were a development of the Bulldogs with strengthened outside frames, of which a total of fifteen were built. A total of 121 Bulldogs were built new, with a further twenty rebuilt from Duke Class locomotives. Thirty Bulldogs were later rebuilt as Earl Class locomotives and renumbered 3265, 3200-3228.

The Great Western Railway 3800 Class, also known as the County Class, were a class of 4-4-0 steam locomotives for express passenger train work introduced in 1904 in a batch of ten. Two more batches followed in 1906 and 1912 with minor differences. They were designed by George Jackson Churchward, who used standard components to produce a four-coupled version of his Saint Class 4-6-0s.

<span class="mw-page-title-main">GWR 3200 Class</span>

The Great Western Railway 3200 Class was a design of 4-4-0 steam locomotive for passenger train work. The nickname for this class, almost universally used at the time these engines were in service was Dukedog since the locomotives were composed of former Duke Class boilers on Bulldog Class frames. As such they were one of the last standard gauge steam locomotive classes to retain outside frames.

<span class="mw-page-title-main">GWR Sir Watkin Class</span>

The Great Western Railway Sir Watkin Class were 0-6-0T broad gauge steam locomotives. They were designed for working goods trains through to the underground Metropolitan Railway in London. This class was introduced into service between December 1865 and the last was withdrawn at the end of the GWR broad gauge in May 1892. They were all named after directors and senior officers of the railway.

<span class="mw-page-title-main">GWR 2884 Class</span> Class of 2-8-0 steam locomotive

The Great Western Railway (GWR) 2884 Class is a class of 2-8-0 steam locomotive. They were Collett's development of Churchward's earlier 2800 Class and are sometimes regarded as belonging to that class.

<span class="mw-page-title-main">GWR 2251 Class</span>

The Great Western Railway (GWR) 2251 Class or Collett Goods Class was a class of 0-6-0 steam tender locomotives designed for medium-powered freight. They were introduced in 1930 as a replacement for the earlier Dean Goods 0-6-0s and were built up to 1948.

<span class="mw-page-title-main">GWR 1400 Class</span> British 0-4-2T steam locomotive class

The GWR 1400 Class is a class of steam locomotive designed by the Great Western Railway for branch line passenger work. It was originally classified as the 4800 Class when introduced in 1932, and renumbered in 1946.

<span class="mw-page-title-main">GWR 4575 Class</span>

The Great Western Railway (GWR) 4575 Class is a class of 2-6-2T British steam locomotives.

<span class="mw-page-title-main">GWR 4500 Class</span>

The Great Western Railway (GWR) 4500 Class or Small Prairie is a class of 2-6-2T steam locomotives.

<span class="mw-page-title-main">GWR 2301 Class</span>

The Great Western Railway (GWR) 2301 Class or Dean Goods Class is a class of British 0-6-0 steam locomotives.

<span class="mw-page-title-main">Charles Collett</span> British railway engineer

Charles Benjamin Collett was Chief Mechanical Engineer of the Great Western Railway from 1922 to 1941. He designed the GWR's 4-6-0 Castle and King Class express passenger locomotives.

<span class="mw-page-title-main">GWR 5800 Class</span> A class of steam tank locomotives

The Great Western Railway (GWR) 5800 Class was a class of twenty 0-4-2T steam tank locomotives. They were built by the GWRs Swindon Works in 1933 and were used for light branch line work. They were similar to the GWR 1400 Class, but lacked the equipment for working autotrains. The last survivor of the class, number 5815, was with withdrawn in 1961. No members of the class were preserved.

<span class="mw-page-title-main">GWR 3000 Class</span>

The Great Western Railway (GWR) 3000 Class was a class of 2-8-0 steam locomotive consisting of the ex-Railway Operating Division ROD 2-8-0. These were built by North British Locomotive Co. between 1917 and 1918. No examples have been preserved.

<span class="mw-page-title-main">GWR 388 class</span>

The GWR 388 class was a large class of 310 0-6-0 goods locomotives built by the Great Western Railway. They are sometimes referred to as the Armstrong Goods or Armstrong Standard Goods to differentiate from the Gooch Goods and Dean Goods classes, both of which were also large classes of standard goods locomotives.

The GWR 378 Class was a class of 30 standard-gauge 2-2-2 steam locomotives on the Great Western Railway in Britain. They were introduced in 1866, and the class remained intact until 1898. Several were altered to the 0-6-0 wheel arrangement, and the last was withdrawn from service in 1920.

<span class="mw-page-title-main">GWR Rheidol Tanks</span> Class of 3 British 2-6-2T locomotives

The GWR Rheidol Tanks are a fleet of 2-6-2T steam locomotives of the Great Western Railway design built between 1923 and 1924. They were designed by the railway's Chief Mechanical Engineer, Charles Collett, for working services on the Vale of Rheidol Railway between Aberystwyth and Devil's Bridge.

The Great Western Railway (GWR) experimented with oil burning steam locomotives at two points in its history. A single experimental tank engine was constructed to burn oil in 1902, and 37 engines of four different classes were converted to burn oil between 1946 and 1950. Neither experiment resulted in the long-term use of oil as fuel for steam locomotives. A single pannier tank locomotive was also converted under British Rail in 1958.

References