# Indian locomotive class YD

The YD class was a class of 2-8-2 tender locomotives built for metre-gauge railways of the British Raj, designed accordingly to the Indian Railway Standard (IRS).

## History

In early 1927, Vulcan Foundry built ten 2-8-2 goods locomotives to the Assam Bengal Railway. Initially unclassified, they would later be known as the class YD/1, as from mid-1927, the YD class was mass-produced for other railway companies in British India as a further development from the original ten examples. The YD/1 were somewhat smaller, and were equipped with three-axle tenders, as opposed to the four-axle bogie tenders used on the YDs.
Between 1927 and 1953, a total of at least 270 locomotives were built by eight manufacturers in Germany, United Kingdom, India, Japan and Czechoslovakia.

### India

When Indian Railways introduced a new numbering scheme in March 1957, the 143 locomotives remaining in service at the time were renumbered 30154–30296. The ten YD/1 class locomotives 30297–30306. By 1975, 133 YD class locomotives were in service with three regional zones of Indian Railways. 71 were allocated to the South Central Railway zone, 45 to Western Railways (including the ten YD/1) and 17 to Southern Railways. Some of the locomotives were in service until the 1990s.

### Pakistan

During the partition of India, several examples came under the ownership of Pakistan Railways. In 1952, Nippon Sharyo of Japan built 25 near-identical locomotives with oil-firing, and were put to work on passenger trains in addition to freight trains. When East Pakistan gained independence as Bangladesh in 1974, the YDs allocated to East Pakistan were inherited by the Bangladesh Railway. Many were in service until the end of steam traction in Pakistan in the 1990s.

### Burma

The colony of Burma was part of the British Raj until 1937, and Burma Railways was under jurisdiction of Indian Railways at the same time. As such, the YD class were used in Burma. After Burma became a separate crown colony and Burma Railways came under the control of the new government, its rolling stock including the YDs were taken over, and a further 20 were acquired in 1949. Some were still in service in 2014.

## Design

The YD class shared the same boiler as the YC class, albeit shorter and with a smaller firebox compared to the latter. The class YD's axle load was 10.2 t, which is the same as with the YB class 4-6-2 locomotives. A heavier 12.2 t axle load variant known as the class YE was proposed, but never built.
Not only the YD/1 class locomotives had differences, some batches of class YD locomotives also had differences. Locomotives that were built in 1933 and 1934 were fitted with poppet valves, while two built for the Gondal State Railway originally did not have superheaters, which were later retrofitted in 1951. Pakistan's Japanese-built locomotives burn oil as fuel.

## Locomotive table

This list may not be complete. Some sources have conflicting statements about the quantity of locomotives produced and operators who initially used them.
| Builder | Year | Quantity | Serial number | Operator | Running number |
| Vulcan Foundry | 1927 | 10 | 4081–4090 | Assam Bengal Railway | 201–210 (YD/1) |
| Vulcan Foundry | 1927 | 5 | 4164–4168 | Assam Bengal Railway | 211–215 |
| Nasmyth, Wilson and Company | 1927 | 2 | 1505–1506 | Bombay, Baroda and Central India Railway | 283, 324 |
| Nasmyth, Wilson and Company | 1927 | 2 | 1507–1508 | Madras and Southern Mahratta Railway | 430–431 |
| Nasmyth, Wilson and Company | 1927 | 7 | 1509–1515 | Burma Railways | 427–433 |
| Škoda | 1928 | 17 | 494–510 | Madras and Southern Mahratta Railway | 448–449, 481, 600–613 |
| Vulcan Foundry | 1928 | 7 | 4226–4232 | Burma Railways | 434–440 |
| Vulcan Foundry | 1928 | 16 | 4233–4248 | Madras and Southern Mahratta Railway | 432–447 |
| Vulcan Foundry | 1928 | 1 | 4249 | Mysore State Railway | 131 |
| Vulcan Foundry | 1928 | 10 | 4250–4259 | South Indian Railway | YD 1–10 |
| Vulcan Foundry | 1929 | 4 | 4399–4402 | Assam Bengal Railway | N/A |
| Vulcan Foundry | 1929 | 10 | 4403–4412 | Nizam’s Guaranteed State Railway | 220–229 |
| Nasmyth, Wilson and Company | 1929 | 1 | 1562 | Gondal State Railway | 1 |
| Swiss Locomotive and Machine Works (SLM) | 1929 | 18 | 3261–3278 | Burma Railways | 441–458 |
| SLM | 1929 | 5 | 3279–3283 | Bombay, Baroda and Central India Railway | 125, 181, 345, 915, 916 |
| SLM | 1929 | 4 | 3284–3287 | South Indian Railway | YD 11–14 |
| Henschel & Sohn | 1929 | 29 | 21544–72 | Burma Railways | N/A |
| AEG-Borsig | 1930 | 1 | 4447 | Gondal State Railway | 2 |
| AEG-Borsig | 1931 | 4 | 4573–4576 | Madras and Southern Mahratta Railway | 482, 616–618 |
| AEG-Borsig | 1931 | 6 | 4577–4582 | South Indian Railway | YD 15–20 |
| AEG-Borsig | 1931 | 2 | 4583–4584 | Madras and Southern Mahratta Railway | 614–615 |
| BB&CI | 1931 | 15 | N/A | Bombay, Baroda and Central India Railway | 142–156 |
| BB&CI | 1932 | 2 | N/A | Bombay, Baroda and Central India Railway | N/A |
| BB&CI | 1932 | 8 | N/A | Mysore State Railway | 134–141 |
| BB&CI | 1933/34 | 15 | N/A | Bombay, Baroda and Central India Railway | 357–371 |
| Vulcan Foundry | 1948 | 5 | 5660–5664 | Nizam’s Guaranteed State Railway | 206–210 |
| Vulcan Foundry | 1949 | 10 | 5705–5714 | Mysore State Railway | 142–151 |
| Vulcan Foundry | 1949 | 20 | 5715–5734 | Burma Railways | 956–975 |
| Vulcan Foundry | 1949 | 9 | 5735–5743 | Nizam’s Guaranteed State Railway | 211–219 |
| Nippon Sharyo | 1952/53 | 25 | N/A | Pakistan Railways | N/A |

## Bagnall-built locomotives

In 1942, two locomotives similar to the YD class built by W. G. Bagnall for Companhia Ferroviária São Paulo-Paraná in Brazil were requisitioned by the War Department and shipped to India in 1943. The Mysore State Railway and the Jodhpur State Railway each received one locomotive. Both locomotives were designated as class YD by Indian Railways, although they bore significant differences. Other than their external appearance, these two locomotives had larger cylinders and firebox. Both were in service in the South Central Railway zone as of 1975.

## Preservation

Several locomotives are on display in various railway museums in India, Bangladesh, Myanmar and Pakistan.

## Gallery

* Vulcan Foundry's specification sheet of the class YD
* Locomotives being built by Swiss Locomotive and Machine Works, 1929
* Pakistan Railways 520 (built in 1932) in service in 1993
* A Japanese-built YD hauling a passenger train, 1993
* Locomotive YD 718 preserved in Bangladesh