Jubilee line

The Jubilee line is a London Underground line which runs between Stratford in East London and Stanmore in North West London. First identified as a separate line in 1979, the Jubilee line is one of the newest line identities on the Tube network, although parts of its alignment date back to sections of the original Metropolitan Railway extensions north of Baker Street. The line is 37.19km (23mi 8ch) in length, just over half of which is in tunnel and serves 27 stations. Passenger service along the line runs mainly from Stratford to Stanmore, although there are scheduled short trips which terminate at North Greenwich in the East and West Hampstead, Willesden Green and Wembley Park in the North.

Route description

Metropolitan Railway Section

The route from Stanmore to Finchley Road is formed entirely from former Metropolitan Railway alignment which was adapted for use by the Bakerloo line in 1939 and subsequently became the Jubilee line from 1979. From Stanmore the line runs above ground in a southerly direction as a two track railway through Canons Park, Queensbury and Kingsbury stations before meeting the Metropolitan line at Wembley Park. Just north of Wembley Park the Jubilee line dives under the Metropolitan line to take it's position as the central pair of London Underground tracks in the mainly six track alignment towards West Hampstead, this is arranged to enable cross platform interchange between Jubilee and Metropolitan line services at Wembley Park and Finchley Road. From Wembley Park the Jubilee line heads south west towards Finchley Road and provides stopping services to Neasden, Dollis Hill, Willesden Green, Kilburn and West Hampstead stations with Metropolitan line services running express on either side and mainline trains running on the south most pair of tracks. The majority of stations on this section include examples of Metropolitan railway architecture, with Willesden Green providing a largely intact example of an early Metropolitan Railway suburban station and Stanmore providing an example of 1920s design, Dollis Hill and West Hampstead also provide classic examples of 1930s style London Passenger Transport Board station architecture. Access is provided to Neasden Depot where a portion of the Jubilee line fleet is stabled overnight from Wembley Park at the north end and from Neasden station at the south end, additional stabling is provided on this section of the line at Stanmore where ten sidings are located. As well as regularly used turnback sidings at West Hampstead, Willesden Green and Wembley Park emergency turnback facilities exist at Neasden and Finchley Road Stations on this section.

1939 construction

From Finchley Road the Jubilee line descends into its central tunnelled section which is formed of classic twin tube tunnels and travels in a broadly southerly direction. This first section of tunnel was excavated between 1933 and 1939 to allow Bakerloo line trains to reach the existing Metropolitan alignment at Finchley Road, this section of line includes Swiss Cottage and St. Johns Wood stations and the Southbound platform at Baker Street. Swiss Cottage and St. Johns Wood stations are both classic 1930s tube stations with a pair of platforms accessed via a central concourse with escalators to the ticket hall.

Jubilee line phase 1

At Baker Street station a pair of junctions allow connection to/from the Bakerloo line, the Southbound connection being located just south of the station and the Northbound connection to the north of the station. From Baker Street the Jubilee line enters the 1979 era tunnels built for the initial Fleet line project continuing in a southerly direction in calls at Bond Street and Green Park stations. From Green Park a short branch exists which runs eastwards to Charing Cross this was meant to form the start of a route from here toward Fenchurch Street and then onwards towards Southeast London. Other than Baker Street the stations on the Phase 1 section of line are typical tube station layout with a pair of platforms located either side of a central concourse, the platform areas are decorated with brightly coloured tunnel linings. This section of line only contains one turnback facility using the former platforms at Charing Cross, to use this facility trains detrain at Green Park and run empty into one of the disused platforms at Charing Cross before returning to Green Park, there are also two stabling sidings located in the overrun tunnels at Charing Cross, although these are not scheduled to be used.

Jubilee Line Extension

To the south of Green Park station a junction allows trains to leaving the Phase 1 alignment and join the Jubilee Line Extension. Heading South trains call at Westminster station before turning east and calling at Waterloo, Southwark, London Bridge, Bermondsey, Canada Water, Canary Wharf and North Greenwich. Just after North Greenwich the line turns to head north and passes under the River Thames for the 3rd time in as many stations and surfaces just before Caning Town station from where it runs in a northwards direction alongside the former North London Line, now DLR, alignment towards Stratford making one more stop at West Ham on the way. There are trains that are regularly scheduled to terminate from the west at North Greenwich, where they use the central platform and a handful of trains in the early morning and late evening carry out the reverse move and terminate at Greenwich from the Stratford direction, emergency turnback facilities also exist at Waterloo, London Bridge, Canary Wharf and West Ham. Stratford Market Depot is the main maintenance depot for the Jubilee line and is located between West Ham and Stratford stations access is possible from both stations. The architecture of the Jubilee Line Extension is highly regarded, and features stations of a scale never before seen on the London Underground with particularly noteworthy Stations being those at Westminster and Canary Wharf.

Current trains

The Jubilee line is operated with a fleet of 63 seven car trains designated 1996 tube stock by London underground. Delivered from 1997 as part of the Jubilee line project the new trains had completely replaced the existing 1983 stock by 1998. While the 1996 stock is externally similar to the Northern lines 1995 stock there are a few external differences between the fleets, mostly around the cab area, there are also significant differences internally and electronically and the two fleets are not interoperable. One notable feature of the 1996 stock is its unique M door arrangement which can both be opened into the cab as a conventional door and swung down to form an emergency staircase. The trains were originally delivered as 59 six car set the trains and were extended to include a 7^th car over Christmas 2005 and an additional 4 sets were delivered by Alstom at the same time. From a technical point of view the sets are formed of two half sets, on three car and one four car with the four car unit at the Stratford end of the train.

Past trains

Despite only being 40 years old as a line the Jubilee line has been operated by three separate fleets of trains. On opening as the Jubilee line 1972 MkII stock was in operation on the line however it was always intended that this would be a stopgap measure pending total fleet replacement following extension of the line towards Southeast London. Delays in the progress of extension beyond Charing Cross resulted in only a small order for new trains being placed in 1982 with only 15 new trains being ordered rather than the 60 anticipated for the fully extended line. These trains designated 1983 MkI stock allowed half the 1972 stock to be displaced to the Northern line, however as they were being delivered an additional 15 1983 MkII sets were ordered. During the planning of the Jubilee Line Extension consideration was given to the conversion of the 1983 stock to run as part of mixed sets with the 1996 stock however this was deemed poor value for money and they were withdrawn. The Jubilee line tracks have also been home to a variety of other train types. 1938 ran on the section north of Baker Street during its time as part of the Bakerloo line and various types of surface stock from its time as part of the Metropolitan Railway and from when Metropolitan line trains used to run over the Jubilee line in the early morning and late evening, additionally the 1986 stock operated sporadic passenger service on the Jubilee line between 1988 and 1989.

Signalling

Since 2011 the Jubilee line has been signalled using the Thales SelTrac signalling system the which is used on several railways globally and in London is also installed on the DLR and the Northern line and is in the process of being fitter to the Subsurface Railway as part of the 4 Lines Modernisation project. On the Jubilee and Northern lines this system is known as Transmission Based Train Control (TBTC) by London Underground and achieves Grade of Automation level 2 (GoA2). The system uses inductions loops located in the four foot of the Jubilee line tracks to track the location of the trains and transmit information between the trains and the signalling system, this allows the system to operate as a “Moving Block” system although the system actually uses 25m long block. As a GoA2 system TBTC allow for full automation of the driving of trains, known as Automatic Train Control (ATC) under the supervision of a Train Operator.

Prior to the installation of ATC on the Jubilee line Metropolitan line trains could run along the Jubilee line tracks between Neasden and Finchley Road with a number of early morning and late evening services scheduled to do so, since 2011 this has not been permitted as the two lines have incompatible signalling. Additionally, the 1996 stock had its tripcocks removed following completion of TBTC installation and so are not permitted on any other lines with the exception of short areas of the Metropolitan line around Wembley Park and Neasden stations which have been fitted with TBTC equipment to allow access to Neasden Depot. It is important to note that the SelTrac installation being rolled out on the Metropolitan line, referred to a Communications Based Train Control (CBTC) by London Underground, uses a radio transmission to communicate with trains and as such will not allow Metropolitan or Jubilee line trains to run over each other’s lines.

Remaining signals

A small number of colour light signals are retained on the Jubilee line for purposes of mixed operations, these signals show a Green Aspect to trains operating on Tripcok rules and a blue aspect for trains using in cab signalling. In the vicinity of Neasden station signals have been retained encase a Metropolitan line train is wrongly routed onto the Jubilee line tracks. At Baker Street southbound platform, a signal allows access from the Jubilee line to the Bakerloo line for engineers’ trains passing between the two. Three further signals which do not have a Green aspect as they are used by trains operating on TBTC are located at the exit points from Stratford Market Depot. Additionally, all moves within Stratford Market and Neasden Depots are conducted in RM mode using position light signals. There are also a handful of disc shunt signals located in the vicinity of Neasden depot which have been overlaid with the Jubilee line TBTC and act in coordination with the in cab signalling display.

Modes of Operation

Trains on the Jubilee line can be operated in three different modes of operation, supervised ATO, full speed manual (PM) and slow speed manaul (RM).

Automatic Train Operation (ATO)

In ATO mode the onboard computer is responsible for driving the train between stations, managing the speed of the train in accordance to the Movement Authority (known as the “Target Point”) provided by the Control Centre. As a GoA2 system the operation of the train is monitored at all times by the Train Operator who is also responsible for opening and closing the doors at each station and handing control to the ATC system by pressing the “ATO Start” buttons once station duties are complete.

Protected Manual (PM)

In PM mode the ATO system is cut out and driving the train is the responsibility of the Train Operator. In PM the operation of the train is still under full supervision of the TBTC system and the Automatic Train Protection (ATP). In this mode the Train Operator drives the train in accordance the Target Point displayed on their in-cab display. While subtle regular and attentive users of the Jubilee line will be able to notice differences in how trains operate between being in ATO and PM modes.

Restricted Manual (RM)

In RM mode the train is operated with limited supervision of the signalling system and with no ATP, consequently it is limited to a maximum speed of 10mph and strict operating rules. RM is only used on the main running line when required due to certain on train or signalling system failures, and only under the verbal authority of the signaller. The procedure for operating a train in RM on the Jubilee line is very similar to that of passing a signal under authority of the signaller on other lines. RM is also the method of operation within Neasden and Stratford Market Depot where position light signals are in use to manage train movements.

History

Metropolitan Railway Era

The first parts of what is now the Jubilee line opened in phases as the Metropolitan Railway extended its route north from Baker Street through to Willesden Green and then on to Wembley Park and Harrow-on-the-Hill. On the 10th December 1932 the Metropolitan Railway opened its final section of track as an independent railway in the form of a branch from Wembley Park to Stanmore.

Bakerloo Line Era

In 1933 the London Passenger Transport Board (LPTB) was formed as the organisation responsible for managing the majority of public transport in London. Following its formation, the LPTB carried out works to divert the Metropolitan line's local services south of Wembley Park as well as the Stanmore branch onto the Bakerloo line, in order to alleviate congestion on the section of line between Finchley Road and Baker Street. This work saw the creation of a new section of tube tunnel between Baker Street and Finchley Road stations as well as the realignment of the lines between Finchley Road and Wembley Park to move the local lines to run between the fast Metropolitan line tracks instead of next to them, work was also conducted at this time to build a new burrowing junction north of Wembley Park to separate trains to Stanmore. Bakerloo line trains began running from Baker Street to Stanmore from 20th November 1939 at which point Metropolitan line services to Stanmore were withdrawn.

Jubilee Line

While the transfer of the local services between Stanmore and Baker Street helped the Metropolitan lines' congestion issues it created new congestion issues for the Bakerloo line with limited terminating capacity at Elephant & Castle and reduced services to Queens Park plans soon emerged for a new line to relieve the Bakerloo line. In 1971 work began on the construction of the first phase of this new line, named provisionally as the Fleet line with new tunnels between Baker Street and Charring Cross calling at Bond Street and Green Park. The work to build Phase one of the Fleet line was completed for opening in 1979 by which time the line had been renamed the Jubilee line to commemorate the Silver Jubilee of Queen Elizabeth II in 1977, the line was officially opened by the Prince of Wales 1st 30 April 1979 with passenger service commencing from 1st May 1979.

Jubilee Line Extension

Charing Cross had never been the intended final terminus of the Jubilee line with the line anticipated to continue eastwards following a route broadly parralelling The Strand, Fleet Street and Ludgate Hill to reach Fenchurch Street station and then on towards Lewisham in South East London, as a result the platforms at Charing Cross were orentated in an East-West direction and around 300m of overrun tunnel was dug which almost reached the anticipated first stop of the Piccadilly line's Aldwych station.