Locomotives in India

Locomotives in India consist of electric and diesel locomotives. Steam locomotives are no longer used, except in heritage trains. Locomotives are also called locos or engines.

The Bengal Sappers of the Indian Army were the first to run a steam locomotive in India. The steam locomotive named ‘Thomason’ ran with two wagons for carrying earth from Roorkee to Piran Kaliyar in 1851, two years before the first passenger train ran from Bombay to Thane in 1853. The steam engine is presently exhibited at Roorkee Railway Station.

Classification of Locomotives

In India, locomotives are classified according to their track gauge, motive power, the work they are suited for and their power or model number. The class name includes this information about the locomotive. It comprises 4 or 5 letters. The first letter denotes the track gauge. The second letter denotes their motive power (Diesel or Electric) and the third letter denotes the kind of traffic for which they are suited (goods, passenger, mixed or shunting).

One of the earliest pictures of railways in India

The fourth letter used to denote locomotives' chronological model number. However, from 2002 a new classification scheme has been adopted. Under this system, for newer diesel locomotives, the fourth letter will denote their horsepower range. Electric locomotives don't come under this scheme and even all diesel locos aren't covered. For them this letter denotes their model number as usual.

A locomotive may sometimes have a fifth letter in its name which generally denotes a technical variant or subclass or subtype. This fifth letter indicates some smaller variation in the basic model or series, perhaps different motors, or a different manufacturer. With the new scheme for classifying diesel locomotives (as mentioned above) the fifth item is a letter that further refines the horsepower indication in 100 hp increments: 'A' for 100 hp, 'B' for 200 hp, 'C' for 300 hp, etc. So in this scheme, a WDM-3A refers to a 3100 hp loco, while a WDM-3F would be a 3600 hp loco.

Note: This classification system does not apply to steam locomotives in India as they have become non-functional now. They retained their original class names such as M class or WP class.

The classification syntaxes

Model of a (decommissioned) WP Steam Locomotive (1:3 size) at Guntur Division.

The first letter (gauge)

W-Indian broad gauge

Y-metre gauge

Z-narrow gauge(2.5 ft)

N-narrow gauge (2 ft)

The second letter (motive power)

D-Diesel

C-DC electric (can run under DC traction only)

A-AC electric (can run under AC traction only)

CA-Both DC and AC (can run under both AC and DC tractions), 'CA' is considered a single letter

B-Battery electric locomotive (rare)

The third letter (job type)

G-goods

P-passenger

M-mixed; both goods and passenger

S-Used for shunting (Also known as switching engines or switchers in United states and some other countries)

U-Electric multiple units (used as commuters in city suburbs)

R-Railcars

For example, in "WDM 3A":

"W" means broad gauge

"D" means diesel motive power

"M" means suitable for mixed(for both goods and passenger)service

"3A" means the locomotive's power is 3,100 hp ('3' stands for 3000 hp, 'A' denotes 100 hp more)

Or, in "WAP 5":

"W" means broad gauge

"A" mean AC electric traction motive power

"P" means suitable for Passenger service

"5" denotes that this locomotive is chronologically the fifth electric locomotive model used by the railways for passenger service.

Broad gauge (5 ft 6 inches) locomotives used in India

Diesel traction

A long distance express train

WDM3A of Pune shed

WDP4 Diesel Locomotive Baaz which is now at New Jalpigudi

WDG-4 numbered 12049 at Hi-Tec station, Hyderabad

WDM-7 numbered 11008 at Ennore

Mixed type locomotives:

WDM 1 (First mainline diesel electric locomotives used in India. Introduced in 1957. Imported from ALCO. Out of service now. 1950 hp)

WDM 2 (Most widely used and first homemade mainline diesel-electric locomotives in India. Original prototypes were made by ALCO. Introduced in 1962. More than 2700 have been made. Rated at 2600 hp)

WDM 2A,WDM 2B (Technical variants of WDM 2)

WDM 3 (Only 8 were imported. They used hydraulic transmission and are currently non-functional)

WDM 3A (Formerly WDM 2C. Another WDM 2 variant. It is not related to WDM 3. 3100 hp)

WDM 3C, WDM 3D (higher powered versions of WDM 3A)

WDM 4 (Entered service along with WDM 2. Prototypes designed by General Motors. Though considered superior to WDM 2 in many ways, these locomotives weren't chosen as General Motors did not agree to a technology transfer agreement. 2600 hp)

WDM 6 (Very rare class; only two were made; one is being used by Puttalam Cement Factory in Sri Lanka. Rated at 1200 HP)

WDM 7

Note: No locomotive class was designated as WDM 5 in India.

Passenger locomotives:

WDP 1

WDP 2 (New class name WDP 3A. Dedicated passenger diesel locomotive. Entered service in 1998. Powerful locomotive. 3100 hp)

WDP 3 (This locomotives are actually prototypes of the class WDP 1 and never entered serial production.)

WDP 4 (EMD (former GM-EMD) GT46PAC, fundamentally a passenger version of the WDG 4 (GT46MAC). 4000 hp)

Goods locomotives:

WDG 2 (New class name WDG 3A. These class is actually a technically upgraded form of WDM 2)

WDG 3B, WDG 3C, WDG 3D (Technical upgraded forms of WDG 2 or WDG 3A)

WDG 4 (New dedicated goods locomotives. These are General motors' GT46MAC models. First units were imported in 1999. They are numbered from #12000 upward. Local production started on 2002. 4000 hp)

WDS-4 Shunting locomotive at Delhi Station

Shunting locomotives (Also known as switching engines):

WDS 1 (First widely deployed and successful diesel locomotives used in India. Imported in 1944-45. currently out of service. 386 hp)

WDS 2 (currently out of service.)

WDS 3 (All locomotives of this class were rebuilt and reclassified as WDS 4C in 1976-78. 618 hp)

WDS 4,WDS 4A,WDS 4B,WDS 4D (Designed by Chittaranjan Locomotive Works. 600-700 hp)

WDS 4C (Rebuilt WDS 3 locos as mentioned above)

WDS 5

WDS 6

WDS 8

Note: There is no electric shunting engine in India. Classes from WDS 1 to WDS 4D have hydraulic transmission. The WDS 4, 4A, 4B, 4C and 4D are the only still existing broad gauge locomotives with diesel-hydraulic transmission.

Diesel multiple units:

A few routes in India currently have Diesel multiple unit service. Depending on the transmission system they are classified as DEMU (diesel-electric transmission) or DHMU (diesel-hydraulic transmission). There are diesel railcar service in a few places known as 'railbus'.

DC electric traction

Note: These locomotives are, or were used only in sections around Mumbai which is the only location in India still using DC traction.

Mixed type locomotives:

WCM 1 ( First electric locomotives with the now familiar Co-Co wheel arrangement to be used in India. 3700 hp)

WCM 2

WCM 3

WCM 4

WCM 5 (Built by Chittaranjan locomotive works to RDSO's design specifications. Auxiliaries by Westinghouse and North Boyce. Built in 1962, these are India's first indigenously designed DC electric locomotives. The first was named 'Lokamanya' after the Congress leader Bal Gangadhar Tilak. 3700 hp)

WCM 6 (A highly powerful class. 5000 hp)

Passenger locomotives:

WCP 1,WCP 2 (GIPR EA/1 and EA/2. Historically very important locomotives as these are the very first electric loco to be used in India. The first locomotive was named as Sir Roger Lumney and is currently preserved in the National Rail Museum, New Delhi. 2160 hp)

WCP 3,WCP 4 (GIPR EB/1 and EC/1, these are also among the earliest electric locos used in India)

The New Delhi Metro railway

Goods locomotives:

WCG 1 (GIPR EF/1. These are Swiss crocodile locomotives imported in 1928 from Swiss locomotive works. These are among the earliest electric locos used in India.The first locomotive was named as Sir Leslie Wilson and is currently preserved in the National Rail Museum, New Delhi. 2600-2950 hp))

WCG 2 (Designed by Chittaranjan locomotive works in 1970.)

Electric multiple units:

WCU 1 to WCU 15 (Used in Mumbai region only)

AC electric traction

WAG-5A at Bhusawal

WAG-7

Mixed type locomotives

WAM 1 (Among the first AC electric locomotives used in India. Introduced in 1959. Now out of service. 3010 hp)

WAM 2

WAM 3

WAM 4 (Indigenously designed by Chittaranjan Locomotive Works in 1970. Highly powerful class. One of the most successful locomotives in India. 3850 hp)

Passenger locomotives

WAP4

WAP 1 (Designed by Chittaranjan locomotive works in 1980 for the Kolkata-Delhi Rajdhani Express. A very successful class. 3900 hp)

WAP 2 (Not in use)

WAP 3 (Not in use)

WAP 4 (Upgraded from WAP 1 for higher loads by Chittaranjan locomotive works in 1994. One of the most successful locomotives in India. Very powerful class. 5350 hp)

WAP 5 (Imported in 1995 from Switzerland and used on premier express trains. 5450 hp)

WAP 6 Only found near Asansol

WAP 7 (Same design as WAG 9 with modified gear ratio. Highly powerful class. 6250 hp)

Goods locomotives

Main article: WAG locomotives

WAG 1

WAG 2

WAG 3

WAG 4

WAG 5 (The most successful electric locomotives in India. Designed by chittaranjan locomotive works in 1984. More than 1100 were made. 3850 hp)

WAG 5A,WAG 5B (Technical variants of WAG 5)

WAG 6A (Imported from ASEA and Hitachi. 6110 hp)

WAG 6B,WAG 6c (Variants of WAG 3A. All rated at 6110 hp)

WAG 7 (Very successful class. Designed by chittaranjan locomotive works. 5000 hp)

WAG 9 (Currently the most powerful class in India, rated at 6350 hp. Same design as WAP 7 with modified gear ratio. Designed by Adtranz, Switzerland.)

Chennai EMU

Electric multiple units

WAU 1 to WAU 4

Dual (both AC and DC) traction

Note: These locomotives are, or were used only in sections around Mumbai which is the only location in India still using DC traction. They can run under AC traction too. The main purpose behind the manufacture of these type of locomotives was to provide transportation in and out Mumbai area without changing the engine.

WCAM3 at Kurla

Mixed type locomotives:

WCAM 1

WCAM 2

WCAM 3(Designed by Bharat Heavy Electricals Limited. 4600 hp under DC traction and 5000 hp under AC traction)

Goods locomotives:

WCAG 1 (Designed by Bharat heavy electricals limited. 2930 hp under DC traction and 4720 hp under AC traction)

Note:There is no dedicated dual current passenger locomotive in India, but in Mumbai area, there are some EMUs which can run under dual traction.

See WCAM Class for more details

Metre Gauge (1 metre) locomotives used in India

Diesel traction (mixed type only)

YDM 1

YDM 2

YDM 3

YDM 4

YDM 4A

YDM 5

Electric traction

Metre-gauge electric loco - YAM1

YCG 1 (These locomotives are among the earliest electric locomotives in India. This class was imported to serve the Chennai area in early 1930s.)

YAM 1 (These locomotives were in service until 2002 around Chennai. 1740 hp)

Electric multiple units:

YAU class (First EMU service in India. Introduced in 1920s in Chennai area)

Narrow Gauge (2.5 and 2 ft) locomotives used in India

Diesel traction (mixed type only)

2 ft 6 inches

ZDM 1

ZDM 2

ZDM 3 (Later rebuilt as ZDM 4C class)

ZDM 4

ZDM 4A

ZDM 4B, 4C, 4D

ZDM 5

2 ft

NDM 1

NDM 5

NDM 6 (These class is currently being used in Darjeeling Himalayan Railway)

Battery traction

NBM 1 Designed by BHEL in 1987. This class was powered by battery.

Note:All narrow gauge locomotives in India are mixed type locomotives.

Special names

Shakthi (Hindi: power): Refers to microprocessor controlled WDG 3A loco (not all WDG 3As are shakti).

Navodit: first 3-phase loco, a WAP 5.

Nav yug(Hindi: new era): a WAP 7.

Prabal: WDM-3A from Lucknow Shed

Nav Jagran

Nav Shakti A WAG 9.

Jawahar : This name is given after India's first prime minister. Jawahar Lal Nehru.

Baaz: a WDP 4 (Only #20011 and 20012 have the name stencilled on. them)

Sukh Sagar Navin BZA WAM-4 #20420.

Baba Saheb: A GZB WAP-1 named after Babasaheb Ambedkar.

Garuda: Microprocessor controlled WDG-2 and WDG-2A locos.

Tiger Face: Refers to those WAG-7 locomotives which have stripes on their front.

(source:wikipedia)