The first line of the extensive Paris Metro network, now owned and operated by RATP, was opened on 19 July 1900. Running from Porte de Vincennes to Porte Maillot, the line was equipped with 3-car trains which had a driving cab at one end only. Semi-circular loops at the terminal stations enabled the trains to be turned. Subsequently, the line has been extended to La Defense in the west and Chateau de Vincennes in the east, making a total of 25 stations with platforms lengthened to take 6 cars. Passenger loadings were initially quite low but nowadays the line carries 750,000 passengers per day making it the most crowded line on the network.
The line was built on the cut and cover principle but at Bastille, where it had to cross the Port de Paris Arsenal water channel, tunnelling techniques could not be trusted so a low level bridge was built. This necessitated steep gradients and very sharp curves which have been a challenge ever since. Running on the north bank of the Seine, the line is always busy; weekdays with people going to work and on business, evenings for theatre and opera goers, weekends with museum, shopping and tourist traffic.
Line 14 and a Modernisation Template
In 2000, RATP took the decision to modernise the complete Metro network. Most lines had infrastructure and trains that were 30-40 years old. So began Project OURAGAN (Hurricane in English) and to understand what this was all about, the rail engineer spoke with Gérald Churchill, the project manager for Line 1 and Ariane Ramboër, the RATP press officer. Gérald had previously been the manager for Line 14 (the Metéor), newly opened in 1998 as the first example of UTO.
Definitions may be needed here: ATO = Automatic Train Operation, retaining a ‘driver’ in the front cab; STO = Semi automated Train Operation, which under new European standards is the revised definition for ATO; DTO = Driverless Train Operation, with no driver but retaining a member of staff on the train as in Docklands Light Railway; UTO = Unattended Train Operation, with no member of staff on board, similar to common practice on airport shuttles.
Line 14 had been built with UTO in mind so the infrastructure was commensurate with the requirements. The line initially carried 140,000 passengers per day but this has risen to 500,000. In 2002, a paper was presented to the RATP Board showing that UTO was workable and that it should be considered for application to an existing line. No-one had tried such a conversion before, but a feasibility study in 2003 showed that it was technically possible, would generate additional capacity and be economically viable.
Line 1 was an obvious choice because of the severe overcrowding. RATP engineers were entrusted with the production of a specification and the subsequent project management with Board approval being given in April 2004. A condition set by the Paris Highways Authority was that train traffic must not be interrupted by the implementation works. The project was split into 5 main elements:
• Replacement of the Rolling Stock;
• Replacing the old STO signalling with a new UTO and the provision of Platform Screen Doors;
• Civil works to adapt the platforms for screen doors;
• New telecom systems in line with UTO requirements;
• Social negotiations to change the conditions of working.
All of these had their challenges, but the platform works and changed conditions of working were the hardest to achieve.
Having no member of staff on a train carries a new set of risks, all of which have to be carefully considered and mitigated. There must be constant supervision of the passengers en route from boarding to disembarking with the ability to deal remotely with any incident that might arise. The basics are:
• UTO of trains with guaranteed stopping position at stations;
• Train cars to be without bulkheads such that an end to end ‘hollow tube’ results;
• Platform screen doors to ensure safe entry and exit from trains;
• Automatic opening of doors at stations once the train is stopped with timed closure of doors depending on the known passenger numbers at any particular station;
• CCTV coverage of every car, each camera being linked by radio to the control room and all pictures recorded for possible police evidence purposes;
• A panic alarm in each car, which when operated automatically brings up the CCTV picture of the car;
• Public address from control to train at any time during the journey;
• Continued movement of the train to the next station if the alarm is activated unless the train is already stopped;
• Easy means of getting staff to the train if a failure occurs.
All the technical elements of these had been tested on Line 14. However, it was one thing installing them on a brand new line, quite another thing applying them retrospectively to an existing one.
Line 1 employed around 250 drivers and, under UTO, they would not be needed. Many drivers were well qualified, often being recruited at graduate level, and RATP was anxious not to use this skill base. Negotiations with the trade unions commenced in 2007 and proceeded on a constructive basis on the presumption that the interests of the company took priority. Various options emerged, the three main ones being:
• Redeploy drivers to another line;
• Keep them on Line 1 until full implementation and then retire them – aimed at the older staff;
• Retrain them for a more senior job on Line 1 such as executives in the Operation Control Centre (OCC) or on stations.
Another short term option has been to create ‘rolling’ teams, positioned every 4-5 stations, to be available to recover or assist trains that encounter a problem, either technical or passenger related. It took time but the negotiations were eventually successful and a formula for the future has been established.
Design and Construction
Fundamental to success was a new, yet proven UTO system. This was competitively tendered with 5 firms invited, all of whom had a system that was in use elsewhere. The contract was awarded to Siemens France – the former Matra Transport company acquired by Siemens in the 1990s. As such, it is a French system. The new system is moving block but operated as a virtual block so that sections remain discrete even though they can be shortened if traffic and speed conditions dictate. The contract required that the new signalling infrastructure had to be superimposed over the old, such that both technologies could be controlled from the new Operations Control Centre. This is similar to methods employed on London’s Victoria line. Equipping an old type MP89 train with the new control equipment enabled test running at night to prove that both old and new systems could operate safely together.
The new trains of type MP05 are being supplied by Alstom from their Valenciennes plant. There are two separate contracts, one to build the trains including all the power equipment and passenger facilities, the other to equip the trains with the VPPI (video protection and passenger information) system. Several sub-contracts were needed for the supply of component parts. The first train was delivered in mid 2008, ready for initial testing at the Valenciennes test track. The second train was delivered to Paris in May 2009 for certification testing and the main production run started in October 2009. Whilst Alstom built the trains, the UTO package was supplied by Siemens, including the train borne equipment. As is often the case, this split responsibility caused a few problems along the way. Gérald reminded me of the English expression, ‘the devil is in the detail’, although with this project ‘the devil is in the interface’!
Radio is the fundamental transmission media, with three separate systems in use:
• Free space propagation using tunnel mounted aerials in the 5.6GHz band for the UTO system;
• WiFi for the video transmission from each car to the OCC;
• Tetra for the voice systems for staff and passengers communication to the OCC.
Each of the new trains has to be equipped with three aerial systems.
Platform Screen Doors
The UTO and telecom systems had all been tried out on Line 14 so applying new versions of the equipment to Line 1 was not too much of a problem. Installing platform screen doors to a working railway was a very different scenario, however, and this turned out to be the biggest challenge. The platforms were found to need reinforcing and increased height. To do this was not a quick process. A joint contract was let to Sogea TPI and Eiffage TP. The concreting was done at night but the station then had to be closed for the concrete to cure. This caused some disruption but, with stations close together, it was considered acceptable for passengers to use adjacent ones.
Once the foundation work was finished, the screen doors were installed at the rate of 3 per night, this work being contracted to the Swiss company, Gilgen Door Systems. It took between 10 and 14 days to install a complete station, Bastille being the worst because of the sharp curves and slants at each end of the platforms. The problems did not end there; with the doors fitted, the old MP89 trains then had to be fitted with antennae to activate the doors and, with the old STO system not having the same accuracy as the new one, would the trains stop in the right space envelope? RATP made visits to London to see how this was managed on the Jubilee Line with manual driving and were reassured that a margin of error could be accommodated. This has proved acceptable and an error rate of 1 in 10,000 has been achieved.
Work Completion and Implementation
By May 2011, all infrastructure work was completed. 13,000 work sites had been needed with up to 100 sites at any one time; in all that period, no major safety incident had occurred. The testing could now begin starting at night and then in the daytime from July, by progressively running new trains in automatic service mode but empty of passengers in between the old trains. This was part of the safety certification process involving Certifer, a French railway certification agency.
Main approval came in September 2011, with final signoff being achieved in November. Eight trains then went into passenger service interspersed with the old trains. This number is gradually being increased as trains are delivered and, at the time of writing, about 20 are in traffic. It will take until Jan 2013 before all new trains are in service. Some technical hitches were encountered once passenger usage started, mainly involving the on-train systems, which took only about 2 weeks to resolve.
Door closure times at known busy stations are set at 50 seconds, elsewhere it is 40. Station dwell times can be remotely changed from the OCC. A critical test came on 9 Jan 2012 when an incident on RER line A caused a shutdown for a period, with many travellers transferring to Line 1. Every possible train was pressed into service and one million passengers were transported in the day. The current headway using a mixed fleet is 105 seconds but this will improve to 85 once the new trains are fully deployed. Signals will remain in place for manual driving in degraded mode operation. Currently a UTO train will not pass a red signal under the ‘overlay’ rules but once all the new trains are in service, the signals will be changed to a blue aspect
The Line 1 upgrade and full automation has cost €600 million. Of this, €400 million has been for the new trains, €150 million for the UTO and telecom systems, and the remainder for the installation of screen doors. The system will be maintained by RATP staff, with initial training being undertaken by the supplying companies. A small separate OCC exists mainly for training purposes but it can also be used for limited functionality operation if disaster recovery is needed.
The displaced MP89 stock, still only 20+ years old, is being transferred to Line 4, replacing older trains in service. Once Line 1 is fully completed, the upgrade of other lines to UTO will be progressed but the procurement process will have to start again. Three new lines may also be constructed to form a Paris Ring – lines Red, Green and Orange – as well as extending Line 14 north and south. All of these will adopt the same UTO operating philosophy. A 2025 completion date is tentatively put forward but this will depend on the availability of finance.
Can UTO be employed elsewhere? Yes, of course it can, and Nuremberg and Lausanne are two such cities where it is in operation. Could it happen in London? The Sub Surface Lines are similar in construction and operation to the Paris Metro but the deep level tubes would need careful thought. One senses that the human factors situation would be quite challenging!