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Above rail services

Rail transport services involving the operation of freight and passenger trains. See also Below rail services.


Access agreement

The terms and conditions under which an accredited rail operator is permitted to operate over track controlled by an infrastructure owner or manager.


Articulated vehicle

Vehicle or vehicles comprising more than one section connected by flexible joints. Most Light Rail Vehicles and some trains are articulated.


Automatic signal

A signal which operates automatically when trains travel on and off track circuits.


Automatic train protection

A range of safety features including the provision of signal information to train drivers via on-board computers, monitoring of train speed and braking, alarm systems and automatic braking if drivers do not obey signals and speed limits.


Axle load

The proportion of a vehicle’s weight carried by each axle. It is calculated by dividing the vehicle’s total weight by the number of axles.



Material usually made of rock that forms the bed that railway tracks are laid on.


Balloon loop

A circular loop of rail line that trains proceed around and reverse their direction of travel.



A long section of railway line on a gradient.


Below rail services

Rail transport services involving the provision of rail infrastructure, including track and signalling. See also Above rail services.


Bi-directional track

Section of track which has signals that enable trains to run in either direction.



Structure underneath a railway or tramway vehicle, including wheels, bearings, brakes and suspension mechanisms.


Braking distance

Maximum distance which any train operating at its maximum authorised speed will travel during a full service application of the brakes, measured from the point where the brake application is applied to the point where the train comes to a stop.


Branch line

Secondary railway or tramway line that branches off from another line.


Broad gauge track

Railway or tramway track with a width of 1600 mm (5 feet, 3 inches) between the rails.



A cushioning device designed to absorb shock that is located on the ends of some railway vehicles.


Buffer stop

Barrier at the end of a track to stop railway or tramway vehicles continuing beyond the end point.


Bulk freight

Freight carried in large quantities, such as iron ore, coal and grain.



Control room of a locomotive, railway or tramway vehicle.


Catch points

A single trailing point blade designed to prevent unauthorised access to a section of track by intentional derailment of vehicle.



System of overhead wires in electrified areas to provide power for electric railway or tramway vehicles.


Centralised Traffic Control

Safeworking and signalling system involving remote control of points and signals at various locations from a centralised control panel.


Colour light signal

Fixed lineside signal using coloured lights to provide indications to train or tram drivers.



See Train consist.


Crossing loop

Section of track forming a loop, enabling trains or trams running on a line with single track to pass each other.



A section of track connecting two parallel railway or tramway tracks, which enables trains or trams to cross from one track to the other.


Distributed power

Distribution of locomotives into intermediate places throughout the length of a train, with intermediate units controlled by the leading locomotive by remote control.



Track arrangement where a railway or tramway track passes under another through a tunnel.


Diesel Multiple Unit (DMU)

Multiple Unit train consisting of a set of diesel-powered self-propelled carriages.


Double heading

Two locomotives combining to haul a train.


Down line

Track usually used by trains proceeding in the direction away from the main terminus.


Down train

Train proceeding in the direction away from the main terminus.


Driving car

Multiple Unit train vehicle with driving controls.

Dual gauge track

Track arrangement enabling trains of two different gauges to operate over the same line, such as standard gauge and narrow gauge. Three parallel rails are laid incorporating a common rail and two other rails.


Electric Multiple Unit (EMU)

Multiple Unit train consisting of a set of electrically-powered self-propelled carriages.



Metal bar bolted to the side of rails to join them together.



Track arrangement where a railway or tramway track crosses another track by means of a bridge or other construction.



Type of articulated steam locomotive comprising a boiler between two steam power units.



Distance between a pair of rails that make up a railway or tramway line, measured from the inside edges of the heads of the rails. Trains and trams are designed to operate on rails of a particular gauge.


Gauge conversion

Alteration of track from one gauge to a different gauge, such as broad gauge to standard gauge.


GenSet (Generator Set)

Type of locomotive that uses two or more small diesel engines and generators rather than a single large engine and generator. Individual engines can be shut down when required to improve efficiency and reduce pollution.


Grade separation

Use of different height levels, such as with flyovers, bridges and tunnels, at the meeting point of different transport routes so that traffic is not disrupted. Grade separation can involve one transport mode, such as railway lines, or more than one transport mode, such as railways and roads.



Slope of a railway or tramway line, expressed as the rise distance over the horizontal run distance. Gradients in Australia are conventionally expressed using “1 in” notation, such as 1 in 40 to represent a slope where the line rises one metre for every 40 metres of horizontal run. The gradient can be calculated as a percentage by dividing the first number by the second number and multiplying by 100. A gradient of 1 in 40 is equivalent to 2.5 %.



Railway enthusiast.



Transverse structure at each end of a locomotive or vehicle’s underframe. The headstocks support coupling equipment and buffers, if fitted. Locomotives and railway vehicles are typically measured by their length over headstocks.


Hi-rail vehicle

See Road-rail vehicle.


Hook and pull

Provision of locomotive and crew to haul a train.



System of signal and point mechanisms that prevents conflicting train movements through junctions and crossovers.


Intermodal freight

Movement of freight using different modes of transport, such as railway, road, ship and air.


Intermodal terminal

Location where freight is transferred between at least two different modes of transport. This typically involves the transfer of shipping containers from rail to road or road to rail.

Island platform

Station layout with a central platform having tracks on both sides. See also Side platform.



Location where two railway or tramway lines diverge from one another.

Lash up

Group of two or more locomotives coupled together.


Level crossing

Intersection of a railway or tramway line with a road and/or a pedestrian path at the same level.


Light engine/locomotive movement

One or more locomotives travelling together without carriages or wagons.


Light rail

Urban public transport system using vehicles like trams but generally of a higher capacity, often operating on a right of way separate from other traffic.


Loading gauge

Maximum dimensions within which a railway or tramway vehicle can safely pass another vehicle or lineside infrastructure.



Railway vehicle that provides the motive power to operate a train, but does not usually carry goods or passengers within the vehicle.



System of remote control enabling lead locomotives to control other locomotives distributed throughout a train by means of radio signals.


Main line

Major line of a railway system.



Mostly underground urban railway system designed to carry passengers over short distances.


Motive power

Locomotives or other railway vehicles that provide tractive effort to operate trains.



Train service on which passengers can take their motor car. Passengers are accommodated within regular passenger carriages, while cars are loaded on to a railway wagon specially designed for carrying motor vehicles.


Motor car

Electric Multiple Unit train vehicle with traction motors. See also Power car, Trailer car.


Narrow gauge track

Railway or tramway track with a width of 1067 mm (3 feet, 6 inches) between the rails.



System of connected railway or tramway lines within a defined area.


Out of gauge

Railway or tramway vehicle that exceeds the loading gauge for a particular section of track.



Bridge over a railway or tramway line.



Device mounted on top of a railway or tramway vehicle to collect electrical current from overhead wires to power the vehicle.


Peak hours

Times when transport networks are most busy, usually between 6.00 and 9.00 am, and between 3.00 and 6.00 pm, on weekdays.


Permanent way

Railway lines, including tracks, sleepers, ballast and associated fixed equipment. The term was developed to distinguish permanent from temporary lines.



Track installation with moveable rails enabling trains or trams to be switched from one track to another.



Closure of one or more railway or tramway tracks to enable work to be carried out.


Power car

  1. Diesel Multiple Unit train vehicle with motors. See also Trailer car.

  2. Electric Multiple Unit train vehicle with equipment to obtain electrical power for the train, such as a pantograph. See also Motor car, Trailer car.


Rack railway

Railway using a toothed rack system to assist trains climbing steep gradients.


Radial steering bogie

A type of bogie fitted to some locomotives, which enables the wheelsets some flexibility of movement within the bogie frame when travelling around curves, with the aims of increasing adhesion and reducing wear on wheels and rails.


Rail corridor

Fenced off area around rail lines. In unfenced areas the rail corridor is generally considered as within 15 metres of the rails.



Self-propelled single or Multiple Unit passenger railway vehicle. Rail motor is generally an older term with the same meaning, but is still used in some circumstances.


Railway-tramway crossing

Crossing where railway and tramway tracks intersect.


Refuge siding

Siding where trains are placed to enable other trains to pass.


Road-rail vehicle

Also known as hi-rail (from highway and railway) vehicle. A vehicle that can run on both roads and railway lines. Road-rail vehicles are usually conventional road vehicles that have railway wheels on the front and rear to enable them to operate on railway lines.


Rolling stock

Railway or tramway vehicles, including locomotives, passenger carriages, freight wagons, trams and light rail vehicles.


Route kilometres

Total length in kilometres of a section or network of railway or tramway lines, regardless of the number of tracks in that section or network. See also Track kilometres.


Run around

Movement involving detaching a locomotive from one end of a train and attaching it to the other end, enabling the train to then proceed in the opposite direction.



Systems and equipment to enable the safe operation of train or tram movements.


Second person

Railway employee who assists the driver of a train.



Railway or tramway line between one location and another.


Semaphore signal

Fixed lineside signal using a moving arm to provide indications to train drivers.



Arrange railway vehicles to form a train or detach vehicles from a train when required.


Side platform

Station layout with a platform at the side of a single or double track. Typically two side platforms are provided on double track. See also Island platform.



Section of railway or tramway track where vehicles can be stored.



Electrical or mechanical device, usually fixed adjacent to track, which provides an indication to train or tram drivers whether they have authority to proceed. There are various types of signals in use throughout Australia.


Signal box

Building that houses signalling equipment to control train or tram movements.



Bars perpendicular to railway tracks that rails are secured to, typically made of wood or concrete.



Process of parking a train or tram when it is not in use.


Standard gauge track

Railway or tramway track with a width of 1435 mm (4 feet, 8½ inches) between the rails.


STN (Special Train Notice)

Information for railway employees about train movements and changes outside of regular timetabled operations.



Location at the end of a railway or tramway line.


Track circuit

Electrical circuit passing through rails which detects trains and other railway or tramway vehicles. The circuit facilitates the operation of signals, level crossings and other equipment.


Track kilometres

Total length in kilometres of all tracks in a section or network of railway or tramway lines; for example, a 20 km section of double track would equal 40 track km. See also Route kilometres.


Trailer car

Multiple Unit train vehicle that does not have motors. See also Motor car, Power car.


Train consist

The arrangement of vehicles that make up a train, including locomotives, carriages and/or wagons. Train composition is an alternative term that is also used.



System of railway lines including three sections in a triangular arrangement that can be used for turning trains in the mode of a three point turn. Triangles are also used at some junctions to enable a train on any line to move directly to either of the two other lines.


Turn up and go

Provision of services frequent enough that passengers do not require a timetable.



Rotating stage that can be used for turning railway vehicles.



Bridge under a railway or tramway line.


Up line

Track usually used by trains proceeding in the direction towards the main terminus.


Up train

Train proceeding in the direction towards the main terminus.


Wheel arrangement

Wheel distribution underneath a locomotive


Working timetable

Schedule of all planned train or tram movements along particular lines, usually for employee use only.



Group of numerous railway or tramway tracks used for storing and arranging vehicles.



System whereby a railway line reverses and then reverses again to enable trains to climb and descend steep gradients.



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