Please could you tell me the absolute number incidents of trains failing to communicate with the signalling system, which are often disingenuously described as 'faulty trains', between Edgware Road, Finchley Road and Euston Square since the implementation of the new signalling system in at the start of September 2019. This is approximately 75 days ago. Can you also tell me the absolute number of incidents of legacy system signal failures between the same stations (Edgware Road, Finchley Road, Euston Square) for the equivalent number of days (approx. 75) prior to the implementation of the new signalling. Please could you also release any internal documentation regarding remedial action being taken to reduce the incidence of non-communicating trains (if any?).

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TfL Refs: FOI-2481-1920

Thank you for your request received by us on 16 November  2019 asking for information about faulty trains.

Your request has been considered in accordance with the requirements of the Freedom of Information (FOI) Act and our information access policy. You asked:

Please could you tell me the absolute number incidents of trains failing to communicate with the signalling system, which are often disingenuously described as 'faulty trains', between Edgware Road, Finchley Road and Euston Square since the implementation of the new signalling system in at the start of September 2019. This is approximately 75 days ago. Can you also tell me the absolute number of incidents of legacy system signal failures between the same stations (Edgware Road, Finchley Road, Euston Square) for the equivalent number of days (approx. 75) prior to the implementation of the new signalling.

Please could you also release any internal documentation regarding remedial action being taken to reduce the incidence of non-communicating trains (if any?).

The Metropolitan, District, Hammersmith & City and Circle lines carry 1.3 million passengers per day, accounting for 40 per cent of the Tube network and 25 per cent of the overall London Underground ridership. Because these lines share a lot of track and infrastructure, we are modernising them under a single combined and integrated project, Four Lines Modernisation (4LM). Our £5.4 billion programme to modernise the signalling on those lines will result in greater capacity and frequency, as well as improved journey times, reliability and customer information. This is the largest single upgrade in the history of the Tube.

Customers have already seen the benefits of the brand new walk-through air conditioned trains. Now we are into the critical stage of introducing the new signalling, including replacing signalling equipment built in 1926. The programme is currently on track to deliver an initial 30 trains per hour service over the south side of the central area in May 2021. Further increases to 32 trains per hour are then planned to be in service across all lines by May 2023.

On 2 September 2019, a section of new digital signalling was introduced from Latimer Road to Finchley Road and Euston Square, with trains operating automatically on those sections of the route. We extensively tested the new signalling during engineering hours and on weekends prior to going live, and this went well. But, while running the new software with the trains in a live environment we have experienced some software reliability issues and there have been a number of incidents of disruption for our customers. These have largely centred around communications issues between software systems on and off the trains.

We have been working with our signalling supplier to identify how to address these issues, and fixes are now being developed. Two software updates are scheduled for late this month and for mid-January next year, which we are confident will improve the situation for our customers.

Unfortunately, to provide the information you have requested would exceed the ‘appropriate limit’ of £450 set by the Freedom of Information (Appropriate Limit and Fees) Regulations 2004. Under section 12 of the FOI Act, we are not obliged to comply with a request if we estimate that the cost of determining whether we hold the information, locating and retrieving it and extracting it from other information would exceed the appropriate limit. This is calculated at £25 per hour for every hour spent on the activities described.

The process of locating all internal documentation across the whole organisation, regarding remedial action being taken to reduce the incidence of non-communicating trains,  would exceed the cost limit described above and so we are refusing this request.

To help bring the cost of responding to your request within the £450 limit, you may wish to consider narrowing its scope so that we can more easily locate, retrieve and extract the information you are seeking. You may find it more beneficial to request specific recorded information rather than broad correspondence requests as this is less likely to generate concerns around the processing time and the potential collation of a lot of information that may not be of significant value to you.

If you want to refine your request or make a Freedom of Information Act request in future, please bear in mind that the Freedom of Information Act allows you to request recorded information held by us. You should identify the information that you want as clearly and concisely as you can, specifying the types of document that you are looking for. You may wish to ask a specific question or for a specific document rather than all internal documentation regarding remedial action being taken to reduce the incidence of non-communicating trains.

Although your request can take the form of a question, rather than a request for specific documents, we do not have to answer your question if it would require the creation of new information or the provision of a judgement, explanation, advice or opinion that was not already recorded at the time of your request.

Please see the attached information sheet for details of your right to appeal.

Yours sincerely

Melissa Nichols

FOI Case Officer

Information Governance

Transport For London

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