The third runway at Heathrow could be a ramp that is built over the M25, the transport secretary has told the BBC.
Building the new runway means having to tackle the problem of it crossing the motorway to the west of the airport, with previous plans having involved a hugely expensive tunnelling project to put the road underground.
Now transport secretary Chris Grayling has floated the idea of an incline at one end of the new runway. Many runways, such as Leeds/Bradford, are built on an incline and it will pose no construction difficulties or safety issues for flights.
As well as hundreds of homes, one casualty of building an additional runway will be British Airways’ Waterside head office at Harmondsworth, which will need to be demolished.
Before any work begins, the government faces numerous hurdles, with four local authorities, including one in Windsor and Maidenhead, prime minister Theresa May’s constituency, preparing legal challenges.