A new rail link between Heathrow and Waterloo has moved a step closer after a major study suggested there was a strong case for the project.
Trains would run between the airport and London Waterloo under the Southern Rail Access proposals which were first mooted many years ago.
It means passengers could travel by rail to the airport from the likes of Guildford, Woking and Basingstoke.
A new feasibility study by Network Rail suggests the work would cost between £700m and £1.8bn depending on which route is chosen.
Network Rail found almost all the options on the table represent either good or very good value, whether or not a third runway is built, though it said further appraisal is needed.
'Huge opportunity to treble rail capacity at Heathrow'
Chris Joyce, head of surface access at Heathrow Airport, welcomed the findings.
"A new rail link connecting Heathrow to south London and Surrey is a huge opportunity to connect an additional 4.8 million passengers to Heathrow, and allow us to treble our rail capacity by 2040.
"This is great news for passengers who will have even more public transport options to and from the airport. It’s also really good news for Heathrow’s neighbours as it will minimise road traffic in the area.
"Southern rail access in addition to Crossrail, Western Rail Link, HS2 via Old Oak Common and an upgraded Piccadilly Line service will place Heathrow at the heart of an integrated rail system, and build on the airport’s strength as the UK's best connected transport hub."
What happens now?
Network Rail's findings suggested a semi-fast Heathrow-Waterloo service, via Richmond, was the best value London link.
A stopping service to Waterloo, with two trains an hour via both Hounslow and Richmond, and a new tunnelled rail line linking Feltham to Heathrow Terminals 2 and 3 in four to five minutes are among the options under consideration.
Hounslow Council earlier this year recommended a new southern link to Heathrow via Feltham, with trains running on an elevated track via a new station in Bedfont.
Network Rail said the study had been carried out to inform the government of the options and enable potential funders to decide whether they merited further development.
Consultation began in February this year over the proposed Western Rail Link to Heathrow, which cut would journey times between the airport and Reading to 26 minutes.