Bi-directional Vehicle

A bi-directional vehicle is a

vehicle A vehicle (from la, vehiculum) is a machine that transports people or cargo. Vehicles include wagons, bicycles, motor vehicles (motorcycles, cars, trucks, buses, mobility scooters for disabled people), railed vehicles (trains, trams), wa ...

that can be driven in either direction, forwards or backwards. Usually, the term refers to

rail vehicle The term rolling stock in the rail transport industry refers to railway vehicles, including both powered and unpowered vehicles: for example, locomotives, freight and passenger cars (or coaches), and non-revenue cars. Passenger vehicles can be ...

s, such as

train In rail transport, a train (from Old French , from Latin , "to pull, to draw") is a series of connected vehicles that run along a railway track and Passenger train, transport people or Rail freight transport, freight. Trains are typically pul ...

s or

tram A tram (called a streetcar or trolley in North America) is a rail vehicle that travels on tramway tracks on public urban streets; some include segments on segregated right-of-way. The tramlines or networks operated as public transport are ...

s, and some airside transfer buses, that are equipped with driver's

cabs C mathematical operations are a group of functions in the standard library of the C programming language implementing basic mathematical functions. All functions use floating-point numbers in one manner or another. Different C standards provide d ...

at both ends. These vehicles generally have entry and exit

door A door is a hinged or otherwise movable barrier that allows ingress (entry) into and egress (exit) from an enclosure. The created opening in the wall is a ''doorway'' or ''portal''. A door's essential and primary purpose is to provide security b ...

s on either side of the vehicle. One major benefit of bi-directional vehicles is the ability to reverse direction at a

terminal station A train station, railway station, railroad station or depot is a railway facility where trains stop to load or unload passengers, freight or both. It generally consists of at least one platform, one track and a station building providing such ...

with a stub-end track. On a system using

double track A double-track railway usually involves running one track in each direction, compared to a single-track railway where trains in both directions share the same track. Overview In the earliest days of railways in the United Kingdom, most lin ...

, a

crossover switch In electronics, a crossover switch or matrix switch is a switch connecting multiple inputs to multiple outputs using complex array matrices designed to switch any one input path to any one (or more) output path(s). There are blocking and non-block ...

is often used to move the vehicle to the other track. This situation contrasts with the use of

uni-directional vehicle A uni-directional vehicle is a vehicle that is normally designed to operate only in the forward direction. While the vast majority of road vehicles are like this, the term generally refers to a train or tram with a distinguishable front and rear ...

s, which requires the use of a

balloon loop A balloon loop, turning loop, or reversing loop ( North American Terminology) allows a rail vehicle or train to reverse direction without having to shunt or stop. Balloon loops can be useful for passenger trains and unit freight trains. Bal ...

triangle junction In railroad structures, and rail terminology, a wye (like the'' 'Y' '' glyph) or triangular junction (often shortened to just "triangle") is a triangular joining arrangement of three rail lines with a railroad switch (set of points) at each c ...

, or

turntable A phonograph, in its later forms also called a gramophone (as a trademark since 1887, as a generic name in the UK since 1910) or since the 1940s called a record player, or more recently a turntable, is a device for the mechanical and analogu ...

to reverse direction. Aside from eliminating the need for complicated railway infrastructure to turn vehicles around, the presence of doors on either side of the vehicle enable the use of

island platform An island platform (also center platform, centre platform) is a station layout arrangement where a single platform is positioned between two tracks within a railway station, tram stop or transitway interchange. Island platforms are popular on ...

s. These extra doors come at the cost of reduction of seating on board the vehicle. Rail transport Vehicles by type {{rail-transport-stub