Wye (rail)

Wyes can also be used for turning railway equipment, and generally cover less area than a balloon loop doing the same job, but at the cost of two additional sets of points to construct and then maintain.

Where a wye is built specifically for equipment reversing purposes, one or more of the tracks making up the junction will typically be a stub siding.

Tram or streetcar tracks also make use of triangular junctions and sometimes have a short triangle or wye stubs to turn the car at the end of the line.

Even where equipment is symmetrical, periodic turning may still be necessary in order to equalize wear (e.g., on the London Underground's Circle Line).

In Canada and the United States, the railroad often was built before other structures, and railway builders had much more freedom to lay down tracks where they wished.

Similarly, when not constrained by space limitations many early Australian railways made use of wyes (particularly in rural locations) for their lower installation and maintenance costs; however, their necessity and use diminished from the 1960s onwards with the major trend in most states toward bidirectional locomotives and railcars.

In tight city environments, this can happen easily, as it did, for example, at Cootamundra West, Australia and Tecuci, Romania, where extra passenger stations had to be built to serve trains taking the shortcut.

The land within a triangle is cut off from the adjacent area (and normally fenced off) and has marginal commercial value, so will be purposed mainly for the railway's exclusive use – generally being used for maintenance depots, storage, or vehicle parking.

On electrified lines substations tend to be located inside triangles, in part because the land is cheap, and also because it provides the most convenient and flexible sectioning arrangements.

[3] Sefton railway station in Sydney lies on one corner of a triangular junction, which allows trains to branch off in either direction without the need to terminate or change ends.

One train a day from Birrong to Sefton does terminate and reverse at Regents Park station (in order to clean the rust off the crossover rails).

[citation needed] There is a goods branch from Chullora and, in the future, the possibility of a separate single track freight line.

Commuter trains on NI Railways are all diesel multiple unit railcars, so they do not need to use the junction as a turning method.

The Luas tram system has a triangular junction on the Red Line between the stations of Busáras, Connolly and George's Dock.

There is a turning triangle partly tunnelled into the mountain at Kleine Scheidegg at the summit of the 800mm gauge Wengernalpbahn in the Bernese Oberland, Switzerland.

Trains normally descend in the direction they have arrived from and are designed accordingly with the power unit at the lower end and seating angled to compensate for the gradient.

Whilst limitations of space dictated that the triangle had to be partly constructed in tunnels it also ensures that in winter it is snow-free and thus readily available in emergencies.

Here the ex-GWR South Wales mainline from London to Swansea is joined by another GWR line from Shrewsbury via Hereford.

A triangle, grid reference SH294789, was provided in 1989 adjacent to the transfer sidings for Wylfa Nuclear Power Station, near to Valley on Anglesey in Wales.

The turntable at Holyhead has long been removed and the area re-developed; the sidings at Valley some 4 miles (6.4 km) from the terminus are the nearest suitable site.

Eventually authority was given to construct a turning arrangement on a strip of spare land to the west of the main line, just south of Grantham station.

Once the switches on the wye are aligned, the train reversed, with the brakeman at the rear of the last car regulating the speed with the brake lever upon approach to the platform.

Then, the head-end cars could be uncoupled from the rest of the train and spotted by a station switcher at the parcel facility where mail and express packages were handled.

The town of Wyeville, Wisconsin, is named after the Union Pacific Railway, formerly the Chicago and North Western Transportation Company wye and crossover nearby.

This section of track is considered a bottleneck for system-wide capacity based on speed restrictions and timing difficulties from distant branch lines.

The southern terminus of the Amtrak Auto Train in Sanford, Florida, uses a wye to turn the locomotives around for the return trip north.

It will allow for transfers from feeder services on the third leg and facilitate more routing options as future phases are completed.

A simple wye
Countryside wye near Lüderitz, Namibia
Illustration of the usage of a wye track for turning a rail vehicle
A park located within a triangular junction in Sydney , Australia
Double track triangle, drawn in one-rail style
Modified triangle at Grantham
The "reversing star" (red) compared to the ordinary wye (blue)