The Anonymous Widower

Can The Signalling Of The London Overground Be Improved?

An article on Modern Railways Online is entitled First To Succeed Arriva On London Overground.

These are two paragraphs of the article.

Under the new concession, which runs for eight years, First Rail London Limited (FRLL) will introduce extra peak time trains on the Mildmay Line from May 2026, more frequent trains on the Windrush Line from December 2026 – up to 18 trains per hour – and upgrade help points and CCTV.

It will also introduce ‘targeted upgrades’ on the Mildmay Line infrastructure to “boost performance for customers.”

It would appear that the signalling is being improved.

So I asked Google AI, the question in the title of this post and received this reply.

Yes, London Overground signalling is actively being improved through major projects like the Windrush Line upgrades (aiming for 18-20 trains per hour) and South London signalling modernisation (Alstom’s new system for better reliability), allowing for increased capacity, faster journeys, and fewer delays, although these upgrades involve planned disruptive works.

It would appear that the improved signalling will lead to more faster and better services.

These have been indicated in the Modern Railways article.

• Extra peak time trains on the Mildmay Line
• More frequent trains on the Windrush Line

I would also expect more freight, open access and other special trains to be able to use London Overground tracks to pass through London.

London has a rail capacity problem, for both freight and passenger trains.

This report from Network Rail is entitled The London Rail Freight Strategy (LRFS).

I have written a series of posts based on this report.

• Decarbonisation Of London’s Freight Routes
• Doubling Harlesden Junction
• East Coast Main Line South Bi-Directional Capability
• Gauge Improvements Across London
• Gospel Oak Speed Increases
• Headway Reductions On The Gospel Oak To Barking, North London and West London Lines
• Heavy Axle Weight Restrictions
• Kensal Green Junction Improvement
• Longhedge Junction Speed Increases
• Moving The West London Line AC/DC Switchover To Kensington Olympia
• Moving The West London Line AC/DC Switchover To Shepherd’s Bush
• Nunhead Junction Improvement
• Stratford Regulating Point Extension
• Will Camden Road Station Get A Third Platform?
• Will Clapham Junction Station Get A Platform 0?

There is certainly work to be performed on London’s railways to increase the total number of freight trains, that pass through and around the capital.

Conclusion

I believe that as has been shown on the Lizzie Line, Thameslink, the East Coast Main Line and other lines around the world, that the number of trains per hour on the Overground can be increased to meet the objectives stated in the Modern Railways article.

What Is The Peak Frequency Of The East London Line?

I asked Google AI, the question in the title of this section and received this reply.

The East London Line (now part of the Windrush Line, London Overground) has peak frequencies of around every 4-6 minutes (10-15 trains per hour) on its busiest sections, though some parts might see higher frequencies, generally offering a very frequent service through East London during peak times. Specific frequency can vary by section (e.g., Stratford-Lewisham, Canary Wharf-Lewisham), but generally, you can expect trains every few minutes during weekday rush hours (around 06:30-09:30 & 16:00-19:00).

I do think that Google AI has got its DLR and its East London Line mixed up.

But even if we accept that current East London Line service needs 15 tph and the new capacity will be the Modern Railways article figure of 18 tph, that’s still an increase of 3 tph through the Thames Tunnel-section of the East London Line.

What Is The Peak Frequency Of The North London Line?

I asked Google AI, the question in the title of this section and received this reply.

The North London Line (NLL), part of London Overground, typically runs 8 trains per hour (tph) during weekday peaks, with plans to increase this with infrastructure upgrades like digital signalling and longer trains to meet growing demand and integrate with Crossrail/HS2. While 8tph has been a target, the line also carries significant freight, impacting passenger service frequency, with older plans aiming for 6-8tph peaks and even longer trains (3-4 cars) for capacity.

The peak frequency of trains on the North London Line appears less than the East London Line, so I would assume, that like the East London Line, it could probably squeeze in another 3 tph.

When you consider that the working day is over eighteen hours, 3 tph means nearly an extra sixty trains per day on both the the East and North London Lines.

Could This Extra Capacity On The East and North London Lines Created By Improved Signalling Be Used For Extra Services?

Consider.

Every train of the service, would need its own path.

• A typical four tph Overground service like Dalston Junction and New Cross would need four paths per hour.
• A typical freight service would need a dedicated path.
• A typical long-distance passenger service would need a dedicated path.

There are certainly possibilities.

December 14, 2025 - Posted by AnonW | Artificial Intelligence, Transport/Travel | Digital Signalling, East London Line, London Overground, North London Line, Signalling