Professional Engineering

The prospect of direct train services from London to Cologne, Frankfurt, and Amsterdam has moved a step closer after the European Railway Agency (ERA) backed plans for the use of rolling stock with a distributed traction system – providing it meets certain safety criteria.

At present, Eurostar has a monopoly on passenger services through the Channel Tunnel and runs only French-built trains by Alstom which feature concentrated power, with the motors and electrical equipment located in power cars at either end of the trains. But train operators such as Germany’s Deutsche Bahn want to launch direct services to other European cities using Siemens-built trains which feature a distributed traction system, whereby the motors are situated under carriage floors.

This has sparked a lengthy technical evaluation of passenger trains operating in the Channel Tunnel by the ERA, the organisation that oversees the application of European rail safety standards. French authorities have questioned the rationale behind plans to change the rules, raising fire safety as a particular area of concern. 

The ERA report makes it clear that the requirements for the Channel Tunnel do not explicitly prohibit distributed power provided that an equivalent level of safety to current trains is demonstrated, requiring a driving position at each end equipped to operate with tunnel signalling. 

But the report said that to maintain the ability to drive through the tunnel in 30 minutes and not lower safety standards, an automatic fire detection and suppression system for motors (traction converters and/or power modules) would need to be specified as a requirement on distributed traction trains. This would see trains with distributed power operating under the same safety standards as trains with concentrated power.

 “The objective of this continuing commitment is to ensure that, as far as practicable, a passenger-carrying train with an on-board fire should be able to exit the tunnel, thus avoiding an in-tunnel evacuation and facilitating intervention by the emergency services,” said the ERA report.

The report also considered other areas of train performance. Requirements for traction for passenger trains are that they must be capable of hauling themselves out of the tunnel from a stand with 50% of traction power available. It was felt that any new rolling stock must meet this performance capability.

Other requirements include a smoke penetration protection system and inflatable door joints, with the objective of ensuring that if a train were on fire in the tunnel smoke would not get into any following train. The ERA concluded that effective smoke penetration sealing would be a requirement for the new trains but stopped short of imposing any particular technical solution. 

The results of the technical assessment also ran strongly against the admission of diesel trains to the tunnel on the grounds of increased fire risk. 

Deutsche Bahn ran a safety test of a Siemens-built high-speed train through the Chunnel in October last year. The state-owned rail group demonstrated that it could run safely on the route, which is being opened up to competition under European Union rules. Deutsche Bahn wants to link directly to London from the end of 2013 using inter-city express ICE3-type trains made by Siemens. These would be capable of reaching 320km/h (200mph).

Ulrich Homburg, member of the Deutsche Bahn management board for passenger transport, welcomed the ERA report. He said: “This is an important stage in securing the technical clearance we need to deliver new high-speed passenger rail services to and from London on Europe’s liberalised rail network. The report confirms that we are heading in the right direction as we work towards clearance of our ICE-trains for the Channel Tunnel.”

Eurostar declined to comment on the implications of the report.