Editing London Underground (section)

===Line improvements===
{{more citations needed section|date=June 2015}}

====Bakerloo line====
The thirty-six 1972-stock trains on the Bakerloo line have already exceeded their original design life of 40 years. London Underground is therefore extending their operational life by making major repairs to many of the trains to maintain reliability. The Bakerloo line will receive new trains as part of the [[New Tube for London]] project. This will replace the existing fleet with new air-cooled [[articulated car|articulated trains]] and a new signalling system to allow [[Automatic Train Operation]]. The line is predicted to run a maximum of 27 trains per hour, a 25% increase on the current 21 trains per hour during peak periods.<ref name="New Tube for London Feasibility Report">{{cite web |title=New Tube for London Feasibility Report |url=https://tfl.gov.uk/cdn/static/cms/documents/ntfl-feasibility-report.pdf |publisher=TfL |date=October 2014 |access-date=25 June 2015 |archive-date=26 June 2015 |archive-url=https://web.archive.org/web/20150626151325/https://tfl.gov.uk/cdn/static/cms/documents/ntfl-feasibility-report.pdf |url-status=dead }}</ref><ref name="Bakerloo line 1972 stock train overhall">{{cite web |title=Bakerloo Line Fleet Life Extension |date=11 March 2015 |url=https://tfl.gov.uk/cdn/static/cms/documents/fpc-20150311-part-1-item15-bakerloo-line.pdf |publisher=TfL |access-date=25 June 2015 |archive-date=26 June 2015 |archive-url=https://web.archive.org/web/20150626133010/https://tfl.gov.uk/cdn/static/cms/documents/fpc-20150311-part-1-item15-bakerloo-line.pdf |url-status=live }}</ref>

====Central line====
[[File:The new Shepherd's Bush Underground station - geograph.org.uk - 2421843.jpg|thumb|The new [[Shepherd's Bush tube station|Shepherd's Bush]] station, part of a [[Central line (London Underground)|Central line]] improvement]]
The Central line was the first line to be modernised in the 1990s, with 85 new 1992-stock trains and a new automatic signalling system installed to allow Automatic Train Operation. The line runs 34 trains per hour for half an hour in the morning peak but is unable to operate more frequently because of a lack of additional trains. The 85 existing 1992-stock trains are the most unreliable on the London Underground as they are equipped with the first generation of solid-state direct-current thyristor-control traction equipment. The trains often break down, have to be withdrawn from service at short notice and at times are not available when required, leading to gaps in service at peak times. Although relatively modern and well within their design life, the trains need work in the medium term to ensure the continued reliability of the traction control equipment and maintain fleet serviceability until renewal, which is expected between 2028 and 2032. Major work is to be undertaken on the fleet to ensure their continued reliability with brakes, traction control systems, doors, automatic control systems being repaired or replaced, among other components. The Central line will be part of the New Tube for London Project. This will replace the existing fleet with new air-cooled walkthrough trains and a new automatic signalling system. The line is predicted to run 36 trains per hour, a 25% increase compared to the present service of 34 trains for the busiest 30 minutes in the morning and evening peaks and 27–30 trains per hour during the rest of the peak.<ref name="New Tube for London Feasibility Report" /><ref name="Report on Central Line train overhaul">{{cite web |title= Central line train overhaul project |url= https://tfl.gov.uk/cdn/static/cms/documents/fpc-20150311-part-1-item16-central-line-overhaul.pdf |publisher= TfL |access-date= 25 June 2015 |archive-date= 26 June 2015 |archive-url= https://web.archive.org/web/20150626134753/https://tfl.gov.uk/cdn/static/cms/documents/fpc-20150311-part-1-item16-central-line-overhaul.pdf |url-status= live }}</ref><ref>{{cite web |title=Central line timetable |url= https://tfl.gov.uk/cdn/static/cms/documents/wtt-67-central-15-september-2013.pdf |archive-url= https://web.archive.org/web/20140415231448/http://tfl.gov.uk/cdn/static/cms/documents/wtt-67-central-15-september-2013.pdf |url-status= dead |archive-date= 15 April 2014 |publisher=TfL |access-date=25 June 2015}}</ref>

====Jubilee line====
The signalling system on the Jubilee line has been replaced to increase capacity on the line by 20%—the line now runs 30 trains per hour at peak times, compared to the previous 24 trains per hour. As with the Victoria line, the service frequency is planned to increase to 36 trains per hour. To enable this, ventilation, power supply and control and signalling systems will be adapted and modified to allow the increase in frequency. London Underground also plans to add up to an additional 18 trains to the current fleet of 63 trains of 1996 stock.<ref>{{cite web |title=Jubilee line 36tph upgrade |url=https://tfl.gov.uk/cdn/static/cms/documents/fpc-20141014-part-1-item-18-jubilee-line-wcc.pdf |publisher=TfL |access-date=25 June 2015 |archive-date=20 April 2015 |archive-url=https://web.archive.org/web/20150420123135/http://www.tfl.gov.uk/cdn/static/cms/documents/fpc-20141014-part-1-item-18-jubilee-line-wcc.pdf |url-status=live }}</ref><ref name="PR20140818">{{cite press release |title=LU to source additional Tube trains |url=https://tfl.gov.uk/info-for/media/press-releases/2014/august/lu-to-source-additional-tube-trains |publisher=TfL |access-date=25 June 2015 |date=18 August 2014 |archive-date=26 June 2015 |archive-url=https://web.archive.org/web/20150626120519/https://tfl.gov.uk/info-for/media/press-releases/2014/august/lu-to-source-additional-tube-trains |url-status=live }}</ref>

====Northern line====
The signalling system on the Northern line has been replaced to increase capacity on the line by 20%, as the line now runs 24 trains per hour at peak times, compared to 20 previously. Capacity can be increased further if the operation of the Charing Cross and Bank branches is separated. To enable this up to 50 additional trains will be built in addition to the current 106 1995 stock. Five trains will be required for the Northern line extension and 45 to increase frequencies on the rest of the line. This, combined with segregation of trains at Camden Town junction, will allow 30–36 trains per hour compared to 24 trains per hour currently.<ref name="PR20140818" /><ref>{{cite web |title=Information on the Northern Line upgrade |url= http://www.railway-technical.com/Northern-Interview-article-for-MR-v5.pdf |publisher= railway-technical |access-date=25 June 2015 |url-status=dead |archive-url= https://web.archive.org/web/20150830075238/http://www.railway-technical.com/Northern-Interview-article-for-MR-v5.pdf |archive-date=30 August 2015 }}</ref>

====Piccadilly line====
The eighty-six 1973 stock trains that operate on the Piccadilly line are some of the most reliable trains on the London Underground. The trains have exceeded their design life of around 40 years and are in need of replacement. The Piccadilly line will be part of the New Tube for London Project. This will replace the existing fleet with new air-cooled walk-through trains and a new signalling system to allow Automatic Train Operation. The line is predicted to run 30–36 trains per hour, up to a 50% increase compared to the 24–25 train per hour service provided today. The line will be the first to be upgraded as part of the New Tube for London Project, as passenger numbers have increased over recent years and are expected to increase further. This line is important in this project because it currently provides a less frequent service than other lines.<ref name="New Tube for London Feasibility Report"/>

====Victoria line====
The signalling system on the Victoria line has been replaced to increase capacity on the line by around 25%; the line now runs up to 36 trains per hour compared to 27–28 previously. The trains have been replaced with 47 new higher-capacity 2009-stock trains. The peak frequency was increased to 36 trains per hour in 2016 after track works were completed to the layout of the points at Walthamstow Central crossover, which transfers northbound trains to the southbound line for their return journey. This resulted in a 40% increase in capacity between Seven Sisters and Walthamstow Central.<ref>{{cite press release |title=Major works to improve Victoria line services this summer |url=https://tfl.gov.uk/info-for/media/press-releases/2015/february/major-works-to-improve-the-victoria-line-over-the-summ |publisher=TfL |date=17 February 2015 |access-date=25 June 2015 |archive-date=24 May 2015 |archive-url=https://web.archive.org/web/20150524035913/http://www.tfl.gov.uk/info-for/media/press-releases/2015/february/major-works-to-improve-the-victoria-line-over-the-summ |url-status=live }}</ref><ref>{{Cite news |url=https://www.guardian-series.co.uk/news/14492247.victoria-line-trains-run-end-end-first-time/ |title=All Victoria Line trains to run 'end to end' for first time |work=East London and West Essex Guardian Series |location=Watford |date=13 May 2016 |first=Tom |last=Barnes |access-date=21 April 2021 |archive-date=10 May 2021 |archive-url=https://web.archive.org/web/20210510042703/https://www.guardian-series.co.uk/news/14492247.victoria-line-trains-run-end-end-first-time/ |url-status=live }}</ref>

====Waterloo & City line====
The line was upgraded with five new 1992-stock trains in the early 1990s, at the same time as the Central line was upgraded. The line operates under traditional signalling and does not use Automatic Train Operation. The line will be part of the New Tube for London Project. This will replace the existing fleet with new air-cooled walk-through trains and a new signalling system to allow Automatic Train Operation. The line is predicted to run 30 trains per hour, an increase of up to 50% on the current 21 trains per hour. The line may also be one of the first to be upgraded, alongside the Piccadilly line, with new trains, systems and platform-edge doors to test the systems before the Central and Bakerloo lines are upgraded.<ref name="New Tube for London Feasibility Report"/>

====Sub-surface lines (District, Metropolitan, Hammersmith & City and Circle)====
{{main|Four Lines Modernisation}}

New S Stock trains have been introduced on the sub-surface (District, Metropolitan, Hammersmith & City and Circle) lines. These were all delivered by 2017. 191 trains have been introduced: 58 for the Metropolitan line and 133 for the Circle, District and Hammersmith & City lines. The track, electrical supply and signalling systems are also being upgraded in a programme to increase peak-hour capacity. The replacement of the signalling system and the introduction of Automatic Train Operation and Control is scheduled for 2019–22. A control room for the sub-surface network has been built in Hammersmith and an automatic train control (ATC) system is to replace ageing signalling equipment dating from between the mid-1920s and late 1980s, including the signal cabin at Edgware Road, the control room at Earl's Court, and the signalling centre at Baker Street. Bombardier won the contract in June 2011 but was released by agreement in December 2013, and London Underground has now issued another signalling contract, with Thales.<ref>{{cite web |title=Tube Improvements |url= https://tfl.gov.uk/campaign/tube-improvements/what-we-ve-done |date=n.d. |publisher=TfL |access-date=25 June 2015 |archive-url= https://web.archive.org/web/20150711143215/https://tfl.gov.uk/campaign/tube-improvements/what-we-ve-done |archive-date=11 July 2015 |url-status=dead }}</ref><ref>{{cite web |title= Third Time Lucky: A Look At The New Sub-Surface Signalling Plan |url= http://www.londonreconnections.com/2015/subsurface-railway-resignalling-saga-continues/ |date= 15 June 2015 |website= London Reconnections |access-date= 25 June 2015 |archive-date= 26 June 2015 |archive-url= https://web.archive.org/web/20150626103653/http://www.londonreconnections.com/2015/subsurface-railway-resignalling-saga-continues/ |url-status= live }}</ref><ref>{{cite web |title=SSR Signalling contract |url=https://tfl.gov.uk/cdn/static/cms/documents/fpc-20150617-item17-part-1-four-lines-modernisation.pdf |publisher=TfL |access-date=25 June 2015 |archive-date=26 June 2015 |archive-url=https://web.archive.org/web/20150626145855/https://tfl.gov.uk/cdn/static/cms/documents/fpc-20150617-item17-part-1-four-lines-modernisation.pdf |url-status=live }}</ref>