Tram-train


A tram-train is a light-rail public transport tram vehicles running through from an urban tramway network to main-line railway lines which are shared with conventional trains. This combines the tram's flexibility and accessibility with a train's greater speed, and bridges the distance between main railway stations and a city centre.
There is also a train-tram, which is a train modified to also run on tramlines. Generally, the tram-train and train-tram are interchangeable, although a train-tram is based on a train design modified to also run as a tram and a tram-train is based on a tram design modified to also run on a train line.
The tram-train concept was pioneered with the Karlsruhe model in Germany, and has since been adopted in Mulhouse in France and in Kassel and Saarbrücken in Germany.

Technology

The tram-train often is a type of interurban, i.e. they link separate towns or cities. according to George W. Hilton and John F. Due's definition.
Most tram-trains are standard gauge, which facilitates sharing track with main-line trains. Exceptions include Alicante Tram and Nordhausen, which are metre gauge.
Tram-train vehicles are dual-equipped to suit the needs of both tram and train operating modes, with support for multiple electrification voltages if required and safety equipment such as train stops and other railway signalling equipment. The Karlsruhe and Saarbrücken systems use "PZB" or "Indusi" automatic train protection, so that if the driver passes a signal at stop the emergency brakes are applied.

History

The idea is not new; in the early 20th century, interurban streetcar lines often operated on dedicated rights-of-way between towns, while running on street trackage in town. The first interurban to emerge in the United States was the Newark and Granville Street Railway in Ohio, which opened in 1889. In 1924, in Hobart, Australia, sharing of tracks between trams and trains was proposed.
The difference between modern tram-trains and the older interurbans and radial railways is that tram-trains are built to meet mainline railway standards, rather than ignoring them. An exception is the United States' River Line in New Jersey which runs along freight tracks with time separation: passenger trains run by day, and freight by night.

Existing systems

Asia

Japan

Austria

Africa

A two-year tram-train pilot project is being undertaken between Sheffield and Rotherham. In the initial phase, from October 2017, Stadler Citylink tram-train vehicles were introduced onto the Sheffield tram network only. Late in 2018, with the completion of a chord at Tinsley connecting Rotherham Parkgate with Meadowhall Interchange, the tram-train vehicles operate on national rail tracks. If the trial proves successful, similar schemes could be rolled out across the UK.
In March 2008 the Department for Transport released details of a plan to trial diesel tram-trains on the Penistone line for two years starting in 2010. There was no commitment to connect them to the Sheffield tram network, and in September 2009 the idea was withdrawn as it was deemed not economically viable for a trial due to the cost of the extra development required for the diesel engines to meet the forthcoming stringent EU emission regulations. Instead single-voltage electric tram-trains will be trialled between Rotherham and Sheffield.
A tram-train trial in the Manchester area was ruled out as the Department for Transport wanted to try low-floor tram-trains, whereas Manchester Metrolink cars have high floors.
In August 2009 the Liverpool Daily Post reported that a new Merseyrail tram-train link to Liverpool John Lennon Airport was under consideration. The Merseyrail Northern line and the City line between and were being assessed. From South Parkway the tram-trains would transfer seamlessly to a new tramway. A link from Edge Hill in the east of the city to the Liverpool Arena at Kings Dock near the city centre was also considered.

Oceania

Models of tram designed for tram-train operation include: