Imagine making a train journey via London. You’d probably rather not – currently such a journey involves carting suitcases from one central London terminal to another. But what if there was another way – if you could take a train towards London and be able to quickly and conveniently transfer onto another railway line without even entering the capital?

This is the dream of a group of independent engineers, Interlinking Transit Solutions Ltd (ITSL), some of whom worked on Skytrain in Vancouver and who have been designing an elevated light transit system following the curves and gradients of the M25 to connect to railway lines where they cross the M25.

The project, called the London Air Rail Transit System (or LARTS Rapid Rail), has evolved both to take account of concerns about lack of capacity, connectivity and resilience of London’s airports, railways and roads and discussions with representatives of many organisations including of airports, airlines, railway companies, DfT, TfL, the Mayor’s office, local government, Chambers of Commerce, multi- disciplinary engineering consultancies, project managers, City solicitors and accountants.

Many existing railway or Underground stations are very close to the M25 (e.g. Byfleet and New Haw, Iver, Kings Langley, Waltham Cross or Epping) while others, (e.g. Staines, Potters Bar, Brentwood or Upminster) would need a short spur line, (and local negotiation) to connect with them.

Because the roads also radiate out of/into London, they too create opportunities for park and ride LARTS stations to reduce car journeys on the M25 or into London. A light rapid transit system remaining within the confines of the motorway in effect adds a railway line that improves capacity, resilience and connectivity for Network Rail.

Using this ‘brown’ land also reduces the need to use the hard shoulder for traffic or widen the motorway in future. We estimate that LARTS will have the environmental benefit of removing about 10,000 vehicles/day on the M25.

To limit motorway disruption, pre- fabricated twin-track guideway sections would be erected at night on piers. These vary in height according to the need to balance visual intrusion against avoiding of existing obstacles.

Generally the guideway would be quite low to pass under bridges. No houses would be demolished – a major factor in planning, delivering and budgeting the project.

Depending on the local situation, LARTS Rapid Rail stations would generally use the elevated construction method to sit over an existing platform. Passengers can make quick transfers between the train and the rapid transit system using a lift or escalator.


Rail connections for airports

The Davies Airports Commission has identified an urgent need for rail access to Heathrow from the south, as has Surrey CC, which is not connected by rail to Heathrow. The Commission also raised the hope of a rail connection between Heathrow and Gatwick through existing junctions.

It is perhaps not surprising that the ‘industry’ has naturally focused on heavy rail options, motorway widening, and airport developments that still regard the car as the most likely form of transport. LARTS challenges those orthodox views with a system that can accommodate first class passengers as well airport workers, plus baggage, mail and freight.

The first stage of LARTS would be from Terminal 5 to Staines where a shuttle service would meet every train arriving at Staines, as at Paris Orly, so providing Heathrow with a peak service to Waterloo of eight trains per hour. We estimate the cost at £400 million.

LARTS can provide the rail connection to Gatwick by extending around the M25 and down the M23. It offers quicker total journey times than heavy rail because the route is shorter along the motorways and passenger walking times are less due to the ability of the system to get right up to the airport terminals. With a line capacity for 10 trains/hr per direction, frequent LARTS Express non-stopping services running on steel wheels at 125kph would take 31 minutes between T5 and Gatwick South. The cost is estimated at about £4 billion using an average figure of £31 million per kilometre.

In extending south of Heathrow, LARTS would be able to have a station at Byfleet and New Haw (Brooklands) to pick up the South West Trains mainline.

The same concept can be applied to Luton airport by constructing a spur up the M1, and passengers could also be delivered to Stansted trains at Waltham Cross station. Connections for Heathrow Hub or Crossrail can also be made.

Extending north of Heathrow would make connections to the Great Western line at Iver, the West Coast Main Line at Kings Langley, and the East Coast mainline at Potters Bar. Avoiding central London not only reduces congestion there, but saves time – Birmingham to Heathrow via LARTS at Kings Langley would save 48 minutes.


Passenger numbers

The Airtrack scheme was forecast to attract about 3.5 million passengers per year. The Airports Commission indicates that inter-airport ridership will be marginal. We estimate it will be about four million passengers per year, which is too low to justify a dedicated heavy rail scheme, let alone a high speed one.

However, LARTS can work with these numbers because it will add passengers from the hubs that are created at existing railway stations and motorway junctions, and it can operate 24 hours a day. LARTS will help to meet the target of 50 per cent of passengers travelling to airports by public transport.

Airport users particularly need public transport 24 hours a day otherwise they use their car. Unlike heavy rail, LARTS is particularly useful for airport staff working early or late, as well as for freight and Royal Mail for which there will be dedicated waggons.

We estimate that three quarters of the 12,600 airport employees living in Surrey may consider LARTS because the total journey time will be more predictable, shorter and cheaper than taking the car all the way into the remote staff car parks. Based on platform and terminus capacities, LARTS can move about 14,000 passengers per hour. We believe this number is roughly the equivalent to a lane of the M25, which should allay fears about restricting further widening of the M25.

Globally tested resilience

Resilience is important for all modes of transport but too often vehicles are stuck on the M25, trains are delayed, and planes sometimes cannot land at their destination. LARTS uses technology and systems that are designed to guard against snow, monsoon rains, flooding, winds, track intrusion, cable theft, and system disruptions. In Vancouver, New York, Beijing, Kuala Lumpur, Dubai and Seoul, system reliability is better than one fault in 12 million journeys and punctuality 98 per cent or better.

Flights that have to be diverted for weather or operational reasons could use another London airport and quickly repatriate crew, passengers and baggage to the original destination using LARTS without having to reposition the aircraft or take buses, which might also be affected.

Heathrow to Gatwick in 31 minutes

The Davies Airports Commission received two other proposals for an orbital railway connecting the airports – one an underground high-speed railway, the other a MAGLEV system. Neither could take the opportunity to integrate with existing railways, so limiting passenger numbers and making them additionally very expensive. Davies dismisses the orbital concept in the words:

‘This option does not deliver the additional capacity that will be required in the future as set out in the assessment of need. Obtaining an acceptable transfer time between airports with some of the concepts presented here would be difficult. The option would entail significant cost. Local environmental costs of the infrastructure are not quantified but there is likely to be significant additional impact.’

With the Commission’s main focus on aviation capacity, it seems not to have noticed that LARTS RapidRail can make a Heathrow/Gatwick connection in 31 minutes; provide the surface access of great connectivity that any airport expansion will require; make the airports more accessible by rail for many more people within or far beyond the M25; reduce vehicle CO2 emissions and congestion on the highways and on central London infrastructure. Nor will LARTS be as significant in cost as many other options that will be needed for surface access connections, and it should attract private finance.