The Anonymous Widower

London Overground: Design Work For West London Orbital Route Begins

The title of this post, is the same as that as this article on the BBC.

This is the sub-heading.

Plans for a new London Overground link in west London are progressing, London’s mayor Sadiq Khan has said.

These paragraphs outline what will happen.

Engineering consultants who worked on the Elizabeth line have been chosen for the West London Orbital service.

“This engineering design will help determine the cost of delivering the scheme, which is currently unfunded,” Transport for London (TfL) said.

It hopes the scheme, which would connect Hounslow with Hendon and West Hampstead, could start next decade.

My feeling, is that they should get on with it.

  • There would be no major construction like tunnels.
  • Four stations would need to be built.
  • I doubt there will be any demolition.
  • It wouldn’t need more electrification, as the route is electrified at both ends and battery-electric trains could be used.
  • It would create more connections to Old Oak Common for High Speed Two.

But if it does for North West London, what the Overground has done for North and East London, it will be very much worth it.

These are a few thoughts and observations.

The Route

This is a schematic of the route from the BBC article.


  1. The new stations are Neasden, Harlesden, Old Oak Common Lane and Lionel Road.
  2. Acton Central, Brentford, South Acton, Syon Lane and West Hampstead Thameslink are step-free and Isleworth is on the way.
  3. The fully step-free Brent Cross West station will open soon.
  4. Lionel Road station will serve the new Brentford stadium.
  5. Old Oak Common Lane will serve High Speed Two, the Elizabeth Line and the North London Line.

They look to be a useful set of stations.

Kew Bridge Station

There’s been a lot of development at Kew Bridge station, since I was last there.

There are lots of flats and Brentford’s new stadium.

I suspect all the stations between Kew Bridge and Hounslow will see similar levels of development.

Electrification Issues On The Dudding Hill Line

The Dudding Hill Line forms the Northern section of the route between the Midland Main Line and the North London Line at Acton Wells Junction.

This map from OpenRailwayMap shows the junction between the Dudding Hill and Midland Main Lines.


  1. The Midland Main Line is shown in red as it is electrified with 25 KVAC overhead wires.
  2. The Dudding Hill Line is shown in black, as it isn’t electrified.

This second map from OpenRailwayMap shows the junction between the Dudding Hill and North London Lines at Acton Wells junction.


  1. As before red tracks are electrified with 25 KVAC overhead wires and black tracks have no electrification.
  2. The Dudding Hill Line is the black track running North-South at the West of the map.
  3. Acton Wells junction, where the Dudding Hill and North London Lines join is in the South-West corner of the map.
  4. The North London Line is shown in red running across the North-West corner of the map.
  5. The Great Western Main Line is shown in red running across the South-East corner of the map.
  6. High Speed Two will run East-West across the map and is shown dotted in red.
  7. The red lines in the middle of the map is the Elizabeth Line depot.

With all the 25 KVAC overhead electrification at both ends of the Dudding Hill Line, it would appear, that if this section is ever electrified, it will be electrified with this form of electrification.

There may be a problem, in that there are three or four bridges over the line.

Electrification Issues At Kew

This map from OpenRailwayMap shows the triangular junction by Kew Bridge station.


  1. As before black tracks have no electrification.
  2. Mauve tracks are electrified with 750 VDC  third-rail electrification.
  3. Kew Bridge station is indicated by the blue arrow at the Eastern point of the junction.
  4. Trains to Hounslow will arrive in the North-East corner of the map and go diagonally across the map to leave in the South-West point of the junction.
  5. Trains to Kew Bridge will arrive in the North-East corner of the map and take the Eastern chord of the junction to a new platform in Kew Bridge station.

Brentford’s new stadium and a lot of housing are in the middle of the junction.

It would seem to be obvious to electrify the triangular junction using 750 VDC third-rail electrification.

But not to the ORR it isn’t, as they won’t allow any new third-rail electrification to be installed on Health and Safety grounds.

Project Management Issues

I believe this could be one of those projects, where by careful selection of the order of the sub-projects, time and money can be saved and passengers will see benefits earlier.

For example.

  • Early delivery of Old Oak Common Lane station would also connect the North London Line to High Speed Two and the Elizabeth Line.
  • Early delivery of step-free access at Kew Bridge station would help passengers going to the new Brentford stadium.

There may be other projects, that need an early delivery.

The Feltham And Wokingham Resignalling Programme

The Feltham And Wokingham Resignalling Programme  is currently underway and there are pairs of new and old signals everywhere between Kew Bridge and Feltham and also between Feltham and Richmond.

These are digital signals and according to Network Rail, they will increase the capacity, which must surely allow the extra trains between Kew Bridge and Hounslow stations.

This signalling project finishes in mid-2024, so I suspect by then the Southern part of the West London Orbital Railway will not have any problems with interaction with other services.

The Feltham And Wokingham Resignalling Programme could be considered an important enabling sub-project of the West London Orbital Railway, that is being performed early.

Richmond Station

As I came through Richmond station, there was an Overground train in Platform 3 and I noticed that Platforms 3 to 5 were allocated to the Overground.

Has the new signalling given Network Rail and train operators more flexibility and extra capacity at Richm0nd?

Currently, the London Overground runs four trains per hour (tph)  between Stratford and Richmond.

The increased flexibility may allow the following.

  • An increase in frequency of trains to Stratford.
  • An increase in frequency of District Line trains, if Ealing Broadway station swaps from being a District to a Piccadilly Line terminus, as I wrote about in Extending The Elizabeth Line – Piccadilly Line To Ealing Broadway.
  • Could Richmond also act as a terminal of the West London Orbital Railway during construction and engineering works?

Another benefit that could be arranged is to run the current four tph London Overground services into Platform 3.

These pictures show a Waterloo-bound South Western Railway train in Platform 2 and a Stratford-bound London Overground train in Platform 3.

As there are 8 tph between Richmond and Waterloo via Clapham Junction, this could be quite a useful cross-platform interchange for passengers going from say Staines or Windsor to Hampstead.



  • The three most likely Northern termini are Brent Cross West, Hendon and West Hampstead Thameslink.
  • There could be other terminals on the North London Line or the Gospel Oak and Barking Line.
  • All possible Northern terminals have 25 KVAC overhead electrification.
  • The two most likely Southern terminals are Hounslow and Kew Bridge.
  • There may be other possible Southern terminals like Twickenham or Richmond.
  • All possible Southern terminals have 750 VDC third-rail electrification.
  • The sections without electrification of the route is less than twelve miles.
  • The ORR won’t allow any new third-rail electrification.

It looks like the trains will need to be dual-voltage with a battery capability.

In this article in Global Rail News from 2011, which is entitled Bombardier’s AVENTRA – A new era in train performance, gives some details of the Aventra’s electrical systems. This is said.

AVENTRA can run on both 25kV AC and 750V DC power – the high-efficiency transformers being another area where a heavier component was chosen because, in the long term, it’s cheaper to run. Pairs of cars will run off a common power bus with a converter on one car powering both. The other car can be fitted with power storage devices such as super-capacitors or Lithium-ion batteries if required. The intention is that every car will be powered although trailer cars will be available.

Unlike today’s commuter trains, AVENTRA will also shut down fully at night. It will be ‘woken up’ by remote control before the driver arrives for the first shift

This was published over twelve years ago, so I suspect Bombardier or Alstom have refined the concept.

In an article in the October 2017 Edition of Modern Railways, which is entitled Celling England By The Pound, Ian Walmsley says this in relation to trains running on the Uckfield Branch, which is not very challenging.

A modern EMU needs between 3 and 5 kWh per vehicle mile for this sort of service.

So for a four-car running for twelve miles, the train would need a battery capacity of between 144 and 240 kWh.

These are not large batteries.

I suspect that the best trains for the route, will be dual-voltage Class 710 trains.

  • The Class 710/2 variant used on the Gospel Oak and Barking Line is dual-voltage.
  • London Overground has 54 Class 710 trains.
  • I am certain, that the batteries needed can be fitted to the trains.
  • Aventras are still in production in Derby.

A test battery-electric version could probably be created and tested on the short Romford and Upminster Line.

There may be other places in London and the rest of the UK, where a four-car battery-electric Aventra would be the ideal train.




April 20, 2023 - Posted by | Transport/Travel | , , , , , , , , , , , , , , , , , , , ,


  1. Indeed, TfL could start running a skeleton D(e)MU/BEMU based service at the next national rail timetable change after Brent Cross West opens (BCW opens soon which is soon but may miss the May timetable change), progressively improving the service as stations are (re)built and the line is electrified.

    The first challenge will be to select a suitable fleet of trains (not sure what is available that is suitable), then do route proving runs, make the minimum station amendments necessary to existing stations, and recruit/train drivers. TfL would also need to let an operating contract.

    It would be nice for the route to use Vivarail D-stock trains (DEMU to start, then maybe BEMU/EMU later). This would suggest letting an initial transitional operating contract for a skeleton service to GWR, as they have some of the Vivarail assets secured for the Greenford branch/shuttle BEMU pilot. If a suitable temporary depot for overnight charging could be agreed, then BEMU service might be possible.

    Longer term I suspect it may be more efficient to operate this as part of the overground with same EMU stock as GOBLIN (buying additional units for capacity expansion for GOBLIN and also WLO capacity, delivering higher capacity trains/service than would be possible with D-stock, as the line could become quite well used).

    Comment by MilesT | April 20, 2023 | Reply

    • I think, this line will have to be run by dual-voltage battery-electric trains. Bombardier designed the Aventras to be battery-electric trains and it will be up to Alstom’s engineers to show what they can do.

      If they can’t then I’m sure Stadler and Hitachi could do a good job.

      I think, that the line will need perhaps 6-8 trains, so it won’t be a big order. But get this line right and there could be large follow-on orders for the replacement of diesel trains.
      I have added a lot more to the original post.

      Comment by AnonW | April 20, 2023 | Reply

      • I also thought Alstom would be a good fit, hence my suggestion to bulk up the order with additional carriages for the GOBLIN.

        Comment by MilesT | April 21, 2023

  2. Surely the Battery Electric, dual-voltage Aventra would be the ideal solution with South West Railways and London Overground respectively running Class 701 and Class 710, Aventra platforms. In that way you could be assured that they would meet the route clearance requirements. Couple that with the lack of work in Derby (Alstom’ s share of the HS2 project will probably only occupy a quarter of its manufacturing footprint) and I think a decent deal could be negotiated.
    Mind you they’ll need to get on with it since apart from HS2 activity it’s about 3 years and 4 months that any rolling stock orders were placed. To put that into context that’s around 6 months longer than the mid-1990s hiatus that wrecked so much of the domestic manufacturing market. Apparently the Rail Minister was due to meet the rolling stock manufacturers and financiers in March because of the threats to up to 20000 UK rail jobs. The meeting is still to happen!
    The future looks bleak to me.

    Comment by fammorris | April 21, 2023 | Reply

    • I wouldn’t be surprised to find, that all political parties are worried about an anti-green backlash. The reaction to the expansion of London’s ULEZ shows that a substantial number of people don’t want restrictions on car usage. Another group don’t want electric cars, because they see the economics as bonkers. If we had a vote on HS2, I suspect the man in the Vauxhall Corsa would vote it down. Are Extinction Rebellion and Just Stop Oil pissing off Joe Public?

      But even Manufacturer or ROSCO funded projects like Hitachi’s Intercity Tri-Mode train and Alstom’s Hydrogen Aventra seem to be making zero progress.

      Comment by AnonW | April 21, 2023 | Reply

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