A medium-capacity system (MCS), also known as light rapid transit or light metro, is a rail transport system with a capacity greater than light rail, but less than typical heavy-rail rapid transit. MCS’s trains are usually 1-4 cars, or 1 light rail vehicle (LRV). Most medium-capacity rail systems are automated or use light rail type vehicles. Light rail is considered high capacity as trains use 2-4 LRVs.
Since ridership determines the scale of a rapid transit system, statistical modeling allows planners to size the rail system for the needs of the area. When the predicted ridership falls between the service requirements of a light rail and heavy rail or metro system, an MCS project is indicated. An MCS may also result when a rapid transit service fails to achieve the requisite ridership due to network inadequacies (e.g. single-tracking) or changing demographics.
In contrast with most light rail systems, an MCS usually runs on a fully grade separated exclusive right-of-way. In some cases, the distance between stations is much longer than typically found on heavy rail networks. An MCS may also be suitable for branch line connections to another mode of a heavy-capacity transportation system, such as an airport or a main route of a metro network.
The definition of a medium-capacity system varies due to its non-standardization. Inconsistencies in international definitions are even reflected within individual countries. For example, the Taiwan Ministry of Transportation and Communications states that each MCS system can board around 6,000–20,000 passengers per hour per direction (p/h/d or PPHPD), while the Taiwan Department of Rapid Transit Systems (TCG) suggests an MCS has a capability of boarding around 20,000–30,000 p/h/d, and a report from the World Bank places the capacity of an MCS at 15,000–30,000 p/h/d. For comparison, ridership capacity of more than 30,000 p/h/d has been quoted as the standard for metro or "heavy rail" standards rapid transit systems, while light rail systems have passenger capacity volumes of around 10,000–12,000 p/h/d or 12,000–18,000 p/h/d. VAL (Véhicule Automatique Léger) systems are categorized in the medium-capacity rail systems because their manufacturer defines their passenger capacities as being up to 30,000 p/h/d. In Hong Kong, MTR's Ma On Shan line could, in some contexts, are classified as a medium-capacity system (as it used shorter four-car SP1950 trains) but can attain up to 32,000 p/h/d which is comparable to the passenger capacity of some full metro transit networks. This classification did not last for much longer as full-length, 8-car trains were being deployed on the line in advance of its extension and transformation into the Tuen Ma line in June 2021. Two other lines, the Disneyland Resort line shuttle service to Hong Kong Disneyland Resort since 2005 and the South Island line since December 2016, are also built to MCS standards.
Generally speaking, medium capacity designation is created from relative lower capacity and/or train configuration comparisons to other heavy rail systems in the same area. For example, the train in an MCS may have a shorter configuration than the standard metro system, usually three (though, in some cases, just two) to six traincars, allowing for shorter platforms to be built and used. Rather than using steel wheels, rubber-tyred metro technology, such as the VAL system used on the Taipei Metro, is sometimes recommended, due to its low running noise, as well as the ability to climb steeper grades and turn tighter curves, thus allowing more flexible alignments.
Fully heavy rail or metro systems generally have train headways of 10 minutes or better during peak hours. Some systems that qualify as heavy rail/metro in every other way (e.g. are fully grade separated), but which have network inadequacies (e.g. a section of single track rail) can only achieve lesser headways (e.g. every 15 minutes) which result in lower passenger volume capacities, and thus would be more accurately defined as "light metro" or "medium-capacity" systems as a result.
In addition to MCS, light metro is a common alternative word in European countries, India, and South Korea.
In some countries, however, light metro systems are conflated with light rail. In South Korea, Light Rail is used as the translation for the original Korean term, "경전철" – its literal translation is "Light Metro", but it actually means "Any railway transit other than heavy rail, which has capacity between heavy rail and bus transit". For example, the U Line in Uijeongbu utilizes VAL system, a variant of medium-capacity rail transport, and is therefore categorized "light metro" by LRTA and others, though the operator itself and South Korean sources refer to the U Line as "light rail". Busan–Gimhae Light Rail Transit is also akin to a light metro in its appearance and features, thought the operator refers it as a "light rail". Likewise, Malaysian officials and media commonly refer to the Kelana Jaya, Ampang and Sri Petaling lines as "light rail transit" systems; when originally opened, the original Malay abbreviations for the lines, PUTRA-LRT (Projek Usahasama Transit Ringan Automatik/Automatic Light Transit Joint Venture Project) and STAR-LRT (Sistem Transit Aliran Ringan/Light Flow Transit System) did not clearly distinguish between light rail and light rapid transit. Some articles in India also refer to some "light metro"-type systems as "light rail". The Light Rail Transit Association (LRTA), a nonprofit organization, also categorizes several public transport systems as "light metro".[† 1]
The main reason to build a light metro instead of a regular metro is to reduce costs, mainly because this system employs shorter vehicles and shorter stations.
Light metros may operate faster than heavy-rail rapid transit systems due to shorter dwell times at stations, and the faster acceleration and deceleration of lighter trains. For example, express trains on the New York City Subway are about as fast as the Vancouver SkyTrain, but these express trains skip most stops on lines where they operate.
Medium-capacity systems have restricted growth capacities as ridership increases. For example, it is difficult to extend station platforms once a system is in operation, especially for underground railway systems, since this work must be done without interfering with traffic. Some railway systems, like Hong Kong and Wuhan, may make advance provisions for longer platforms, for example, so that they will be able to accommodate trains with more, or longer cars, in the future. Taipei Metro, for example, constructed extra space for two extra cars in all its Wenhu Line stations.
See also: List of metro systems
The following is the list of currently-operating MCSs which are categorized as light metros by the Light Rail Transit Association (LRTA) as of March 2018[update], unless otherwise indicated.
The list does not include, for example, monorails and urban maglev, despite most of them also being "medium-capacity rail system".
|Bulgaria||Sofia||Sofia Metro – Line 3||1||2020||Driverless vehicle system – 60-metre-long (200 ft) trains; Siemens chosen as technology supplier|
|Canada||Toronto||Toronto subway — Line 3||1||1985||Categorized by APTA as being "intermediate rail" (i.e. between "heavy rail" and "light rail"), and categorized as a "light metro" by LRTA.|
|Vancouver||SkyTrain||2||2002||While using equipment typically employed in medium-capacity systems, the Expo line approaches the capacity of a full "rapid transit" system since it operates with longer 4- and 6-car Bombardier Innovia Metro trains. However, the Canada Line operates with 2-car Rotem trains.|
|China||Beijing||Beijing Subway - Yanfang line, Capital Airport Express||2||2008||Capital Airport Express uses 4-car L-type trains, 60m long. Yanfang line uses 4-car B-type trains, 75m long.|
|Changchun||Changchun Rail Transit - Line 3, Line 4, Line 8||3||2002||All three lines use light rail vehicles, with line 3 also having level crossings.|
|Dalian||Dalian Metro - Line 3, Line 12, Line 13||3||2002||Uses 4-car B-type trains, with some trains on line 3 having 2 cars.|
|Guangzhou||Guangzhou Metro - Line 4, Line 6, Guangfo line, and Zhujiang New Town Automated People Mover System||4||2005||Lines 4 and 6 use 4-car L-type trains, 67m long. Guangfo line uses 4-car B-type trains, 75m long. Zhujiang New Town Automated People Mover uses 14 Bombardier Transportation's APM 100 cars built in Pittsburgh, Pennsylvania.|
|Nanjing||Nanjing Metro - Line S6, Line S7, Line S8, Line S9,||4||2014||Lines S6, S7, and S8 use 4-car B-type trains, 75m long, while line S9 uses 3-car B-type trains, 57 m long.|
|Shanghai||Shanghai Metro - Line 5 (branch), Line 6, and Pujiang Line||3||2003||Line 5 branch and line 6 use 4 car, ~75m long, C-type trains. Pujiang line uses 11 Bombardier Transportation's APM 300 cars.|
|Tianjin||Tianjin Metro - Line 9||1||2004||Line 9 uses 4-car B-type trains, 75m long.|
|Wuhan||Wuhan Metro - Line 1||1||2004||Line 1 uses 4-car B-type trains, 75m long.|
|Hong Kong||Disneyland Resort Line
(Penny's Bay Rail Link)
|1||2005||Trains: 4 compartments without drivers. Some of the M-Train cars used in the Disneyland Resort line were originally ordered from 1994–1998 as subtype H-Stock train (Phase 3 EMU, A/C 270–291, B/C 486–496). Units A/C274 A/C281 A/C284 A/C289 A/C291 and B/C490 are now used on the Disneyland Resort line.|
|South Island line||1||2016||Trains: 3-car S-Trains. Categorized as a "medium-capacity rail transport system".|
|Macau||Macau Light Rapid Transit||1||2019||Uses Mitsubishi Heavy Industries Crystal Mover APM vehicles with rubber tyres running on concrete tracks. Mitsubishi supplied 55 two-car trains that are fully automated (driverless) and utilise a rubber-tyred APM system. They have a capacity of up to 476 passengers.|
|Denmark||Copenhagen||Copenhagen Metro||4||2002||Driverless vehicle system. Trains: 3-car config., 39 metres (128 ft) length.|
|France||Lille||Lille Metro||2||1983||VAL people mover system. Trains: 2-car config., 26 metres (85 ft) in length, with a passenger capacity of 208–240 per train (depending on VAL 206 or VAL 208 train). UrbanRail.net describes it as a "new generation of metro systems".|
|Paris||Orlyval||1||1991||VAL people mover system, using VAL 206 vehicles.|
|Rennes||Rennes Metro||2||2002||VAL people mover system – while trains have 80 second headways, they can only carry 158 people per train. Described as a "mini-metro line".|
|Toulouse||Toulouse Metro||2||1993||Although a VAL system, LRTA defines the system as "Metro." On the other hand, UrbanRail.net describes it as a "light metro VAL system".|
|India||Gurgaon||Rapid Metro Gurgaon||1||2013||Driverless vehicle system. The line is designed to carry up to 30,000 passengers per hour. Several articles define the system as "light metro."|
|Italy||Brescia||Brescia Metro||1||2013||Trains: 3-car config, 39 metres (128 ft) length.|
|Catania||Catania Metro||1||1999||Single-tracked at-grade section limits headways to 15 minutes. Currently 4.6 kilometres (2.9 mi) of double track extension are under construction.|
|Genoa||Genoa Metro||1||1990||Generally considered to be a "light metro" considering its low frequency, limited hours of operation and reduced transport capacity. It is actually categorized as "light rail" by LRTA.|
|Milan||Milan Metro: Line 4 and Line 5||2||2013, 2022||Driverless vehicle system. Trains: 4-car configuration, 50.5 metres (166 ft) length, capacity for 536 passengers.|
|Naples||Naples Metro||1||1993||Line 6 is categorized as "light metro", with only 16 minute headways. Line 1 has a single-tracked tunnel section.|
|Perugia||MiniMetro||1||2008||LRTA defines the system as a "light metro," while they regarded the same system in Laon, which ceased in 2016, as a "cable monorail."|
|Turin||Turin Metro||1||2006||VAL people mover system.|
|Japan||Hiroshima||Astram Line||1||1994||Driverless vehicle system. A small part of the underground section was built as Metro system.|
|Kobe||Kobe New Transit||2||1981, 1990||Trains: Port Island Line and Rokkō Island Line. Both consist of 4-car config (300 people per train), but the platforms are made for fitting to 6-car config.|
|Osaka||Nankō Port Town Line||1||1981||Trains: 4-car config, but the platforms are designed to apply to 6-car.|
|Saitama||New Shuttle||1||1983||Trains: 6-car config, rubber-tyred and operated manually.|
|Sakura||Yamaman Yūkarigaoka Line||1||1982||Trains: 3-car config (205 people per train). An AGT with center-guideway system. Because of the form, LRTA defines the system as a monorail.|
|Tokorozawa||Seibu Yamaguchi Line||1||1985||Trains: 4-car config (302 people per train), rubber-tyred and operated manually. Not mentioned LRTA nor UrbanRail.net.|
|Tokyo||Nippori-Toneri Liner||1||2008||Trains: 5-car config, driverless vehicle system.|
|Yurikamome||1||1995||Trains: 6-car config, driverless vehicle system.|
|Yokohama||Kanazawa Seaside Line||1||1989||Driverless vehicle system.|
|Malaysia||Kuala Lumpur||Rapid KL – LRT Kelana Jaya, LRT Ampang and LRT Sri Petaling||2||1998, 1996||Bombardier INNOVIA ART 200 Trains: Mixed 2-car, 4-car config. fleet.|
|Philippines||Manila||LRT Line 1||1||1984||Trains: Line began with 2-car configuration, reconfigured to 3-car in 1999, and procured new 4-car trains in 1999, 2006, and 2022. Line was originally designed for 18,000 p/h/d capacity, increased to 40,000 p/h/d in 2006. Categorized as "light rail" by LRTA.|
|MRT Line 3||1||1999||Trains: 3-car config., with a max. capacity of 1,182 passengers, and running with 3.5–4 minute headways. 4-car trains with a max. capacity of 1,576 passengers were introduced in 2022. However, line is designed for 23,000 p/h/d capacity, expandable to 48,000 p/h/d.|
|Russia||Moscow||Moscow Metro: Line 12 – Butovskaya Line||1||2003||Can carry 6,700 p/h/d. Trains: 3-car config, ~85 metres (279 ft) length|
|Singapore||Singapore||Singapore MRT: Circle line, Downtown line, Thomson-East Coast line and Jurong Region line (future)||4||2009, 2013, 2020, 2027||The Circle line rolling stock consists of Alstom C830 and C830C trains in 3-car formations with a capacity of 931 passengers. The Downtown line rolling stock consists of Bombardier C951 & C951A trains also in 3-car formations with a capacity of 931 passengers. The Thomson-East Coast line rolling stock consists of Kawasaki Sifang CT251 trains in 4-car formations with a capacity of 1,280 passengers. The Jurong Region line rolling stock will consist of Hyundai Rotem CJ151 trains in 3-car formations with a capacity of 600 passengers.|
|South Korea||Busan||Busan Metro Line 4||1||2009||Unmentioned by LRTA, though UrbanRail.net categorizes the line as a "light metro."|
|Busan–Gimhae Light Rail Transit||1||2011||Driverless vehicle system. Trains: 2-car config. Unmentioned by LRTA, but the operator calls the system "light rail".|
|Gimpo||Gimpo Goldline||1||2019||Each train consists of 2-car trains and runs unmanned.|
|Incheon||Incheon Subway Line 2||1||2016||Each train consists of 2-car trains and runs unmanned.|
|Seoul||Ui LRT||1||2017||Each train consists of 2-car trains and runs unmanned.|
|Sillim Line||1||2022||Each train consists of 2-car trains and runs unmanned.|
|Uijeongbu||U Line||1||2012||VAL driverless system. Trains: 2-car config. |
Categorized as a "light metro" by LRTA and elsewhere, though there are also articles categorizing it as "Light Rail."
|Yongin||Yongin Everline||1||2013||Driverless vehicle system applied.|
|Spain||Barcelona||Barcelona Metro: Line 8 and Line 11||2||2003||Driverless vehicle system. Trains: 2-car config. LRTA also categorizes Line 8 as "light metro."|
|Málaga||Málaga Metro||1||2014||System contains at-grade intersections on surface section of Line 1. Described as a "light metro" by at least one rail publication.|
|Palma, Majorca||Palma Metro: Line M1||1||2007||Mostly underground line operates with just 15-minute headways and two-car trains (306 passengers max.); one reference even categorizes line as "light rail".|
|Seville||Seville Metro||1||2000||Trains: 31.3 metres (103 ft) length with a max. capacity of 280 passengers. Described as a "light metro" by rolling stock manufacturer, CAF.|
|Taiwan||Taipei||Taipei Metro: Wenhu/Brown Line (Line 1) and Circular/Yellow Line||2||1996, 2020||Brown Line (Line 1) – Trains: Rubber-tire system; 4-car config; categorized as a part of the "metro" by LRTA. |
Yellow Line – 4-car AnsaldoBreda Driverless Metro vehicles, categorized as a "light metro" by LRTA.
|Taichung||Taichung Metro: Green Line||1||2021||2-car EMU.|
|Thailand||Bangkok||Bangkok MRT: MRT Purple Line||1||2016||3-car configuration|
|Turkey||Ankara||Ankaray Light Metro (A1 Line)||1||1996||Trains: 3-car config, approx. 90 metres (300 ft) length. Categorized as a "light rail" by LRTA, though Current capacity: 27,000 p/h/d.|
M1 Line (Istanbul Hafif Metro)
|1||1989||Trains: 4-car config. "Hafif Metro" literally translates as "Light Metro". Categorized as a "light rail" by LRTA.|
|United Kingdom||Glasgow||Glasgow Subway||1||1896||Gauge: 4 ft (1,219 mm). Trains: 3-car config.|
|London||Docklands Light Railway||7||1987||Driverless vehicle system. Trains: generally 2–3-car config. Categorized as a "light rail" by LRTA.|
|United States||Detroit||Detroit People Mover||1||1987||Considered to be a "people mover".|
|Honolulu||HART (planned)||1||2023||under construction|
|Miami||Metromover||3||1986||Considered to be a "people mover".|
|Philadelphia||Norristown High Speed Line
(part of the SEPTA rail system)
|1||1907||Has been categorized by APTA as being "Light rapid rail transit" (i.e. between "rapid transit (heavy rail)" and "light rail").|
|Venezuela||Maracaibo||Maracaibo Metro||1||2006||Trains: 3-car trainset config, ~58 metres (190 ft) length (originally designed for Prague Metro). Categorized as a "light rail" by LRTA.|
|Valencia||Valencia Metro||1||2007||Trains: 2-car Siemens SD-460 config, ~55 metres (180 ft) length. Categorized as a "light rail" by LRTA.|
The following is the list of former-MCSs that either developed into a full rapid transit system, or which are no longer in operation: