Locomotives of India

• First letter (gauge):
  • W – Broad gauge (wide) – 5 ft 6 in (1,676 mm)
  • Y – Metre gauge (yard) – 1,000 mm (3 ft 3 ³⁄₈ in)
  • Z – 2 ft 6 in (762 mm) narrow gauge
  • N – 2 ft (610 mm) narrow (toy) gauge
• Second letter (motive power):
  • D – Diesel
  • C – DC electric (DC overhead line)
  • A – AC electric (AC overhead line)
  • CA – DC and AC (AC or DC overhead line); CA is considered one letter
  • B – Battery (rare)
• Third letter (job type):
  • G – Goods
  • P – Passenger
  • M – Mixed (goods and passenger)
  • S – Shunting (switching)
  • U – Multiple unit (electric or diesel)
  • R – Railcar

In WDM 3A, W denotes broad gauge; D denotes diesel power; M denotes mixed use (goods and passenger service), and 3A denotes 3,100 hp (2,300 kW) (3,000 + 100). In WAP 5, W is broad gauge; A is AC electric; P is passenger service, and 5 indicates that the locomotive is the fifth model used.

Indian Railways locomotives: (clockwise from upper left) Preserved HPS, NRM WP 7200, B-26 and preserved YP-class

Nineteenth-century railway companies ordered custom-built locomotives, usually from British manufacturers. The multiplicity of similar-but-not-identical designs increased manufacturing cost and slowed production. During the 1890s, British manufacturers were busy and Indian railway companies looked to Germany and the United States for locomotives.[2] Engines used were:

• Bengal Nagpur Railway:
  • Class F: 0-6-0
  • Class GM: 2-6-0 (probably modified)
  • BNR class HSG: 2-8-0+0-8-2 Garratt, India's first successful Garratts
  • Class M: 4-6-2 (probably modified)
  • BNR class N: 4-8-0+0-8-4 Garratt, India's largest locomotive. One is preserved at the National Rail Museum, New Delhi
  • BNR class NM: Similar to N class; ten were built in 1931 by Beyer Peacock, and it was withdrawn in the late 1960s.
  • BNR class P: 4-8-2+2-8-4 Garratt; four were built by Beyer Peacock in 1939. During the early 1970s, they were at the Bhilai (BIA) shed before being withdrawn.
• Bombay, Baroda and Central India Railway:
  • BB&CI class P: 4-6-2
  • Class A: 2-4-0T, probably an Atlantic; was at the Palej shed.
  • Class U36: 0-4-2, used on hauling suburban trains in Bombay
  • Class D1: 4-4-0; one was named Princess May.
  • Class M: 4-6-2 (probably modified)
• East Indian Railway Company:
  • Class CT: 0-6-4T, probably converted to a superheater.
  • EIR class G: 2-2-2T. First two named Express and Fairy Queen. Built in 1855, the latter is the world's oldest locomotive to be in working order. Later rebuilt by Perambur Loco Works. Housed at East Indian Railway (EIR)
  • EIR class P: 4-6-0
• Great Indian Peninsula Railway:
  • GIPR classes Y1, Y2, Y3, and Y4: 0-8-4T. Used on Thal Ghat as bankers for pushing trains up the Western Ghats.
  • GIPR Class F and F3: 2-6-0
  • GIPR class J1: 0-6-0
  • Class D4: 4-6-0; one is named Hero.
  • Class D5: 4-6-0 passenger locomotive
  • Class E1: 4-4-2 Atlantic built by the North British Locomotive Company in 1907–8. Rebuilt with a superheater between 1925 and 1928.
  • Class T: Tank locomotive used for hauling Mumbai suburban trains
  • Class Y: 2-8-4T
  • Crane tank: 0-6-0T; one is preserved at the National Rail Museum in New Delhi.
• Madras and Southern Mahratta Railway:
  • M&SM class V: 4-4-0; one is preserved.
  • Class BTC: 2-6-4T, based on BESA specifications
  • Class T: 0-4-2; one is preserved in Madras.
• Nizam's Guaranteed State Railway:
  • NSR class A: 2-6-0T (No. 48, probably an Atlantic) preserved at the National Rail Museum, Delhi.
• North Western State Railway:
  • Class EM: 4-4-2 (probably modified); one is preserved at the National Rail Museum
  • NWR class GAS: 2-6-2+2-6-2 Garratt; one built in 1925, and retired in 1937.
  • NWR class P: 2-4-0
  • Class E1: 4-4-2
  • Class N1: 4-8-0
• Oudh and Rohilkhand Railway:
  • Class B26: 0-6-0; one is preserved at the National Rail Museum.
• Others:
  • Class B: 2-6-0
  • Class E: 2-4-0
  • Class F: 2-8-2, built between 1926 and 1950 by Nasmyth Wilson for service on Central Railway (CR).
  • Class G: 2-6-0, probably intended for freight
  • Class NA2
  • Class PTC: 2-6-4T, owned by Northern Railway (NR); probably a converted passenger locomotive
  • Class Y2: 2-8-2T, reclassified L2
  • Phoenix: 0-4-0T; one is at the National Rail Museum.
  • Ramgotty: 2-2-0T; the National Rail Museum's oldest locomotive, it was converted to broad gauge.
  • Sultan, Sahib and Sindh: Hauled the train from VT to Thana in 1853.

Vulcan Foundry class SPS, 1911

After acrimonious words in The Times and Parliament, the British Engineering Standards Committee (later the British Engineering Standards Association) began designing a series of locomotives for use by Indian railways. The first two designs emerged in 1903: a 4-4-0 passenger and 0-6-0 goods. They were revised in 1905 and 1906 with additional heavier, more-powerful locomotives:

• Class SP: Standard passenger (4-4-0)
• Class SG: Standard goods (0-6-0)
• Class PT: Passenger tank (2-6-4T)
• Class HP: Heavy passenger (4-6-0)
• Class AP: Atlantic passenger (4-4-2)
• Class HG: Heavy goods (2-8-0)
• Class HT: Heavy tank (2-8-2T)

These advisory BESA designs were customized by the railway companies, which used different classification systems; only the state-operated railways used the class designations SP, SG, PT, HP, AP, HG and HT. When superheating was accepted, superheated versions were classified SPS, SGS and so on (if built with superheaters) and SPC, SGC and so on (if converted from saturated to superheated).

Indian Railways locomotives: 1935 XP class (left) and 1927 XB class

After World War I, larger and more-powerful locomotives were designed by British consulting engineers for the Indian government. They began to appear in 1927:

• Class XA: branch passenger 4-6-2 design, 12.5-ton axle load
• Class XB: light passenger 4-6-2 design, 17-ton axle load
• Class XC: heavy passenger 4-6-2 design, 19.5-ton axle load
• Class XD: Light goods 2-8-2 design, 17-ton axle load
• Class XE: heavy goods 2-8-2 design, 22.5-ton axle load
• Class XF: light shunting 0-8-0 design, 18-ton axle load
• Class XG: heavy shunting 0-8-0 design, 23-ton axle load
• Class XH: 4-cylinder 2-8-2, 28-ton axle load; none were built
• Class XP: experimental passenger 4-6-2, 18.5-ton axle load
• Class XS: experimental 4-cylinder 4-6-2, 21.5-ton axle load
• Class XT: light tank 0-4-2T, 15-ton axle load

During World War II, large numbers of 2-8-2 locomotives were acquired from the United States and Canada and classified AWD and CWD. The Baldwin Locomotive Works adapted the USATC S160 Class locomotive design for India, and it became class AWC. Sixty broad-gauge locomotives were built in 1944 as part of an order of 180 S160 engines. In addition to modified frame spreaders, axles, cylinders, and cab, the Indian locomotives had a turbo generator and electric lighting (not included in the standard European design). Many parts (including boilers) were identical to those in standard-gauge locomotives.[3]

(clockwise from upper left) WL- and YG-class locomotives; an M2-162, and a display engine in Guntur Division

Although new classes were designed shortly before the war, many did not enter service until the post-war period. The new classes were indicated by the change of broad-gauge prefix from X to W, and plans were implemented to begin manufacturing locomotives in India. The new classes were:

• Class WP: passenger 4-6-2, 18.50-ton axle load
• Class WG: goods 2-8-2, 18.50-ton axle load
• Class WL (1st): light 4-6-2, 16.00-ton axle load (four for North Western Railway in 1939; all to Pakistan during partition of India)
• Class WL (2nd): light 4-6-2, 16.75-ton axle load
• Class WM: 2-6-4T, 16.25-ton axle load
• Class WT: 2-8-4T, 18.00-ton axle load
• Class WU: 2-4-2T, 16.50-ton axle load
• Class WV: 2-6-2T, 16.25-ton axle load
• Class WW: 0-6-2T, 16.50-ton axle load

All broad-gauge steam locomotives in India have been withdrawn from normal service, with only occasional steam specials continuing to operate.

Broad-gauge diesel classification codes are:

• WDM – Wide diesel mixed
• WDP – Wide diesel passenger
• WDG – Wide diesel goods
• WDS – Wide diesel shunter
• WCDS – Wide converted diesel shunter

Name	Manufacturer	Wheel Arr	Quantity Built	Built year(s)	Power	Current Status	Preserved units	Comments	Picture
WDS-1	GE	Bo-Bo	15	1944-1945	386 HP	Retired	1	India's first diesel locomotive
WDS-2		C	30	1954-1955	440 HP	Retired
WDS-3		C	7	1961	618 HP	Retired
WDS-4	CLW	C	27	1968-1969	600 HP	Few are still in service	4	A few still in service
WDS-4A	CLW	C	5	1968	660 HP	Retired
WDS-4B	CLW	C	450	1969	700 HP	Retired
WDS-4C	CLW	C	7	1976-78	700 HP	Retired
WDS-4D	CLW	C	120	1984-97	700 HP	Retired
WDS-5	ALCO/DLW	Co-Co	21	1967	1065 HP	In service		A few still in service
WDS-6	DLW	Co-Co	270	1975–	1400	In service	2 Earmarked
WDS-6AD	DLW	Co-Co	270	1975–	1400	In service	2 Earmarked
WDS-8	CLW	Bo-Bo	5	1979-1982	800 HP	Retired

Indian Railways DHMU (left) and DEMU

The WCDS6, a YDM4 locomotive, was converted to broad gauge by the Golden Rock Railway Workshop for large industrial companies; the first one was delivered to RITES. New water and air lines were added, the control stand was modified, and it has a dual brake system.

A few routes have DMU service. Depending on their transmission system, they are classified as DEMU (diesel-electric transmission) or DHMU (diesel-hydraulic transmission). There is diesel railcar service (known as railbus) in several areas.

Broad-gauge AC electric classification codes are:

• WAM – Wide AC electric mixed
• WAP – Wide AC electric passenger
• WAG – Wide AC electric goods

Name	Builder	Wheel Arrangment	Quantity Built	Built year(s)	H.Power	Current Status	Preserve	Comments	Picture
WAG-1	Niv./SFAC/ CLW	B-B	112	1963-1966	2930 HP	Retired	1 unit
WAG-2	Hitachi /Toshiba /Mitsubishi	B-B	45	1964-1965	3450 HP	Retired	None
WAG-3	Henschel/CLW	B-B	10	1965	3300 HP	Retired	None
WAG-4	CLW	B-B	186	1966-1971	3590 HP	Retired	None
WAG-5	CLW/BHEL	Co-Co	1196	1978-1998	4360 HP	In service	1 unit
WAG-6A	ASEA	Bo-Bo-Bo	6	1988-1989	6110 HP	In Service	1 unit
WAG-6B	Hitachi	Bo-Bo-Bo	6	1988	6110 HP	In service	1 unit
WAG-6C	Hitachi	Co-Co	6	1988	6110 HP	In service	1 unit
WAG-7	CLW/BHEL	Co-Co	1970	1992	5350 HP	In service	1 unit earmarked
WAG-8	BHEL	Co-Co	1	1991	5000 HP	Retired	None
WAG-9	ABB / CLW/BHEL	Bo-Bo	1840	1996–present	6125 HP	In service
WAG-10	DLW	Co-Co-Co-Co	1	2018–present	10000 HP	In service
WAG-11	DLW	Co-Co-Co-Co	3	2019–present	11000 HP	Undergoing Trials
WAG-12	Alstom	Bo-Bo-Bo-Bo	8	2018–present	12000 HP	In service

• Electric multiple units are designated WAU-1 to WAU-4.

These locomotives, no longer in use, were used only in and around Mumbai with 1,5 kV DC power. All sections of Central Railway, including Thane to Mumbai CST (Main Line), Nerul to Thane (Trans-Harbour Line), Vadala Road to Mahim (Harbour Line, connecting Central and Western Railway) and Panvel to Mumbai CST (Harbour Line) have been converted to 25 kV AC.

Broad-gauge DC electric classification codes were:

• WCM – Wide DC electric mixed
• WCP – Wide DC electric passenger
• WCG – Wide DC electric goods

Name	Manufacturer	Wheel Arr	Quantity Built	Built year(s)	Power	Current Status	Preserved units	Comments	Picture
WCG-1	SLM / MetroVick /Vulcan Foundry	C+C	41	1928-1929	2600-2890 HP	Retired	2 units
WCG-2	SLM / MetroVick	Co-Co	57	1970-1976	4200 HP	Retired	2 units

WCU 1 to WCU 15 electric multiple units (EMU) were used in the Mumbai region.

These locomotives are used only in the Mumbai area. Their main purpose is to prevent the need to change engines. Mixed locomotives are:

Name	Builder	Wheel Arr	Quantity Built	Built year(s)	Power	Current Status	Preserved units	Comments	Picture
WCAM-1	CLW	Co-Co	54	1975-1979	2930 HP DC 3640 HP AC	Retired	None	First mainline with AC/DC electric locomotive and the only Indian electric loco with reversed pantographs
WCAM-2	BHEL	Co-Co	20	1995-1996	3780 HP DC 4720 HP AC	In service
WCAM-3	BHEL	Co-Co	53	1997-1998	4600 HP DC 5000 HP AC	In service

In 1927, English Electric and WBC built two shunters for yard use in Bombay with Bo-Bo bogies. Rated at 240 hp (180 kW), they weighed 58 tons. These are now preserved in National Rail Museum in Delhi. They were charged using the 1500 V DC OHE which was available there.[4]

These locomotives are used on routes that run on both electrified and non-electrified tracks. Their main purpose is to prevent the need to change engines. Passenger locomotives are:

Name	Builder	Wheel Arrangement	Quantity Built	Built year(s)	Power	Current Status	Preserved units	Comments	Picture
WDAP-5	DLW	Co-Co	1	2019–present	4500 HP Diesel 5500 HP AC	Undergoing Trails		India's first dual-mode locomotive

• Nilgiri Mountain Railway X class
• BESA designs:
  • Passenger (4-6-0)
  • Mixed (4-6-0)
  • Goods (4-8-0)
  • Tank (2-6-2T)
• Indian Railway Standards designs of the late 1920s
  • Class YA: 4-6-2 with 9-ton axle load (none built)
  • Class YB: 4-6-2 with 10-ton axle load (161 built for India and 50 for Burma)
  • Class YC: 4-6-2 with 12-ton axle load (15 built for India and 13 for Burma)
  • Class YD: 2-8-2 with 10-ton axle load (171 built for India, 61 for Burma, and 25 for East Pakistan)
  • Class YE: 2-8-2 with 12-ton axle load (none built)
  • Class YF: 0-6-2 with 8-ton axle load; later examples were 2-6-2 (111 built for India)
  • Class YK: 2-6-0 version of the 2-6-2 YF, 8-ton axle load (25 built for India)
  • Class YT: 0-4-2T with 8-ton axle load (2 built for India)
• Wartime designs:
  • Class MAWD: 2-8-2 USATC S118 Class
  • Class MWGX: 4-6-2+2-6-4 Garratt
• Indian Railway Standards post war designs
  • Class YL: 2-6-2 mixed traffic locomotive with 8-ton axle load (264 built 1953–1957)
  • Class YG: 2-8-2 goods locomotive with 10½-ton axle load (1074 built 1949–1972)
  • Class YP: 4-6-2 passenger locomotive with 10½-ton axle load (871 built 1952–1968)
  • Class YM 2-6-4T with 9-ton axle load (12 built 1956)

YAM 1 metre-gauge electric locomotive

• Locomotives:
  • YCG 1: Among India's earliest electric locomotives, the class was imported to serve the Chennai area in the early 1930s.
  • YAM-1: Twenty 1,740 hp (1,300 kW) locomotives, imported from Japan, were in service until 2004 in the Chennai area.
• Electric multiple units:
  • YAU class: India's first EMU service was introduced around 1920 in the Chennai area.

• Barsi Light Railway:
  • Class A: 0-8-4T
  • Class B: 4-8-4T
  • Class C: 0-6-0ST
  • Class D: 0-4-0
  • Class E: Sentinel railcars
  • Class F: 2-8-2
  • Class G: 4-6-4
• Indian Railway Standards:
  • Class ZA: 2-6-2 with 4.5-ton axle load (none built)
  • Class ZB: 2-6-2 with 6-ton axle load
  • Class ZC: 2-8-2 with 6-ton axle load (none built)
  • Class ZD: 4-6-2 with 8-ton axle load (none built)
  • Class ZE: 2-8-2 with 8-ton axle load
  • Class ZF: 2-6-2T with 8-ton axle load

DHR B class locomotive in Darjeeling shed (1979)

• Darjeeling Himalayan Railway:
  • DHR A Class: 0-4-0WT;
  • DHR B Class: 0-4-0ST; #777 and #778 preserved
  • DHR C Class: 4-6-2
  • DHR D Class: 0-4-0+0-4-0 Garratt
• Indian Railway Standards (none built):
  • QA: 2-6-2 with 4.5-ton axle load
  • QB: 2-6-2 with 6-ton axle load
  • QC: 2-8-2 with 6-ton axle load

• ZDM-1: (at Gwalior Junction)
• ZDM-2: (Kalka Shimla Railway)
• ZDM-3: (rebuilt as ZDM 4C)
• ZDM-4: (at Gwalior Junction)
• ZDM-4A:
• ZDM-5:

• 
  ZDM-2
• 
  ZDM-3
• 
  ZDM-4A
• 
  ZDM-5

NDM-1 diesel loco on the Matheran Hill Railway.

• NDM-1: Matheran Hill Railway
• NDM-5: Gwalior Light Railway
• NDM-6: Darjeeling Himalayan and Matheran Hill Railways

• NBM-1: Designed by BHEL in 1987