Since the new signal systems were installed on the Met line, how many minor and severe delays have occurred regardless of cause and how many occurred in the same period prior to new signal system installed?

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TfL Ref: FOI-2455-1920

Thank you for your request received by Transport for London (TfL) on 13^th November 2019 asking for information about delays on the Metropolitan Line.

Your request has been considered in accordance with the requirements of the Freedom of Information Act and our information access policy.

Specifically you asked:

“Since the new signal systems were installed on the Met line, how many minor and severe delays have occurred regardless of cause and how many occurred in the same period prior to new signal system installed?”

There were 86 cases of Severe and Minor Delays in the 81 day period prior to the introduction of the new signalling (on 2^nd September 2019) and 275 in the same time period after the introduction of the new signalling. The data is based on the Service Status on the Metropolitan Line as recorded by the London Underground Control Centre, up to and including 20^th November 2019. Not all of these instances of delays would have been related to the new signalling system.

We are investing £5.4 billion to modernise the trains, track and signalling on the oldest parts of the Underground – the Metropolitan, District, Hammersmith & City and Circle lines. This work will improve journeys on 40 per cent of the Tube network, and is the largest single upgrade in the history of the Underground. It will result in greater capacity and improved frequency, as well as improved journey times, better reliability and better customer information. 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.

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 ongoing 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. We have carried out modifications to the trains' communications systems as well as the line's signalling system to improve the reliability of the interface between the train, the signalling system and the equipment on the ground, to mitigate the breakdown of communications which can cause trains to become "non-communicating" and therefore unable to operate. Two software updates are scheduled, which we are confident will improve the situation for our customers. We are reviewing our plan for maintaining the existing older signalling to make the best use of resources to minimise the impact of any signal failures. We have extra staff and technical experts on duty, and teams meeting trains at Finchley Road and Euston Square to fix issues immediately. We have also deployed incident response managers at key points along the line to aid service recovery.

We fully understand how frustrating this is for customers, and we apologise for the disruption that they are currently facing. We are working 24-7 and taking every measure possible to tackle the delays and improve the service as soon as possible.

If this is not the information you are looking for please do not hesitate to contact me.

Please see the attached information sheet for details of your right to appeal as well as information on copyright and what to do if you would like to re-use any of the information we have disclosed.

Yours sincerely,

David Wells

FOI Case Officer

FOI Case Management Team

General Counsel

Transport for London

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