Network Rail is evaluating responses to a 3.4-mile proposed link from west of Heathrow Airport to Terminal 5.

The link would leave the Great Western Main Line (GWML) at a new junction between Langley and Iver stations and connect to the existing railway at Terminal 5. It would allow four trains per hour to run in each direction from Reading to Heathrow via Slough, with alternate services calling at Twyford and Maidenhead.