Medium-capacity rail system

When the predicted ridership falls between the service requirements of a light rail and heavy-rail rapid transit 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 light rail systems,[2] an MCS runs on a fully grade separated exclusive right-of-way.

An MCS may also be suitable for branch line connections to another mode of a heavy-capacity transport system, such as an airport or a main route of a metro network.

[3] 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.

For example, the Taiwan Ministry of Transportation and Communications states that each MCS system can board around 6,000 to 20,000 passengers per hour per direction (p/h/d or PPHPD),[7] while the Taiwan Department of Rapid Transit Systems (TCG) suggests an MCS has a capability of boarding around 20,000 to 30,000 p/h/d,[8] In Hong Kong, MTR's Ma On Shan line was locally classified as a medium-capacity system (as it used shorter 4-car SP1950 trains, compared to 7- to 12-car trains on other MTR lines) but can attain up to 32,000 p/h/d which is comparable to the passenger capacity of some full metro transit networks.

In addition to MCS, light metro is a common alternative word in European countries, India,[10][11] and South Korea.

CRRC Zhuzhou LRV Trains: 6-car configuration The following is the list of former-MCSs that either developed into a full rapid transit system, or which are no longer in operation: