Translohr

Translohr is a rubber-tyred tramway (or guided bus) system, originally developed by Lohr Industrie of France and now run by a consortium of Alstom Transport and Fonds stratégique d'investissement (FSI) as newTL, which took over from Lohr in 2012. It is used in Paris and Clermont-Ferrand, France; Medellín, Colombia; and Venice-Mestre and Padua in Italy. In June 2012, Alstom Group and the Strategic Investment Fund acquired Translohr for €35 million.

Description

The Translohr system is intended to provide a tram or light rail-like experience compared to regular buses or trolleybuses. Unlike other guided bus systems (including the similar but incompatible Guided Light Transit system developed by Bombardier Transportation), Translohr cars are permanently fixed to guide rails, and cannot divert from them, similar to traditional steel-wheeled rail vehicles.

Since the guide rail automatically guides the vehicle along its route, accelerating and braking are the only functions the driver controls. Like a conventional tram, power is provided by overhead wires and collected with a pantograph. The vehicle can also be run on internal batteries (arranged in packs) on sections of the route without overhead wires.

There are two main designs for the vehicles: the bi-directional STE series, and the unidirectional SP Prime series. They consist of three to six articulated sections like a conventional tram, with a length from  long and  wide. Their net weight is , depending upon the number of car sections.

Translohr LRVs cannot run without a guide rail, therefore they are not classified as buses. Hence, vehicles that are used on the Clermont-Ferrand network do not have license plates.

Criticism
The  Châtillon–Viroflay Line in Paris cost €27.4m per km, including infrastructure, improvements of the right-of-way, and the purchase of 28 STE6 vehicles. In addition, due to the tyres constantly running over the same area of road, there is significant erosion of the roadway; this has already happened with Bombardier Guided Light Transit transit system, resulting in extensive repairs at significant cost to the operator. This adds to already high running costs. Providing roll ways embedded in the pavement might have been useful. Such rollways are used on rubber-tyred metros. Ride quality is also said to be poor and is not much of an improvement over a standard bus due to the four-wheeled design, whereas trams have trucks (bogies) with shock absorbers or springs. 

The Tianjin system suffered a derailment on 20 August 2007, three months after its inauguration. There were five derailments on Padua's new installation in 2007 before its inauguration, and one on 22 April 2010 due to a misaligned switch.

Where snowfall is an issue, this system may not be practical: since the guide rail forms the return leg of the electrical circuit, accumulation of ice and snow on the rail could cause intermittent power interruptions to the vehicle. Also, as the vehicle does not place a significant portion of its weight on the guide wheels (most of it being supported by the rubber tyres), snow packed into the flangeways or atop the rail by road traffic might possibly lift the guide wheels off the rail, leading the vehicle to go off course. Since the guide wheels each grip the guide rail at a 45-degree angle and thus are at 90-degree angle to each other, the risk for such case may be minimal, however such conditions may cause the wheels to lose grip and become slippery.

Critics of the system also point out that, unlike a conventional tramway, Translohr is a proprietary system, meaning that once it is installed, a city would suffer vendor lock-in, or difficulties in buying vehicles from any manufacturer other than Lohr Industrie. When the patents shall have expired, this will no longer be an issue.

There are several lines under construction or already built, which were eventually abandoned or shut down due to planning changes and operational difficulties. For example, L'Aquila, which started demolition work in 2013; Latina, which purchased new vehicles in 2016 but did not put them into operation because the infrastructure was not completed; Shanghai Zhangjiang Tram, which was demolished shortly after it stopped running on June 1, 2023; TEDA Modern Guided Rail Tram , after the shutdown on June 1, 2023, a tender announcement for demolition work is issued in July 2023.

See also

 CRRC Autonomous Rail Rapid Transit
 List of rubber-tyred tram systems 
 Right-of-way (transportation)
 TEDA Modern Guided Rail Tram
 Tram
 Tramways in Île-de-France

References

Further reading

External links
 

Bus terminology
Rubber-tyred tram
Tram vehicles of China
Tram vehicles of France
Tram vehicles of Italy