Clamp on cars as trains take the plane at Heathrow's new terminal

BAA, the company which owns Heathrow airport, yesterday stepped up its campaign to be allowed to build a fifth terminal by announcing plans for a variety of new rail links and promising that the amount of new car parking spaces would be capped at 20,000.

The airport is already due to be connected by railway for the first time in the summer of 1998 with the pounds 350m Heathrow Express and yesterday BAA said that it was in negotiation with five potential private operators to bring trains in to the station.

Options include running one train per hour to both Birmingham and Manchester, operating a frequent service to St Pancras in north London, connecting with Thameslink or running local trains to either Watford Junction or Acton.

There is also a study being undertaken by the consultants Halcrow to link Heathrow with the Reading-to-Waterloo line. But another scheme, to join Heathrow with the Great Western line in a westerly direction creating scope for direct trains from the South West and Wales, has not attracted any interest from the existing train operators, GWR and Thames, because it would need electric trains and they only operate diesels.

While BAA's plans will be met with enthusiasm by supporters of rail, so far no money has been committed towards any scheme and no decision has been taken between options that are mutually exclusive because of the limited amount of capacity.

Moreover, BAA has refused to name most of the potential private operators with whom it is having discussions although Virgin has already expressed an interest in the St Pancras connection.

If Terminal 5, currently the subject of a planning inquiry which is not due to end for at least another year, is given the go ahead, there could be as many as 16 trains per hour arriving at the airport. However, if permission is not received, the maximum would probably be eight per hour, of which half will be the Heathrow Express service linking the airport to Paddington with a 16-minute journey.

The plan for rail links is part of BAA's determination to show that the new airport terminal would not jam up local roads in north-west London. The announcement of the proposals coincided with the publication of BAA's evidence to the public inquiry on surface access to the new terminal. As part of the company's policy, it has said that it will increase parking charges by an average of 25p per visit in order to raise extra funds for public-transport provision and it has committed itself to a cap of 55,000 on the number of parking spaces at the airport, compared with the current level of 35,000, all but 10,000 of which are run by BAA.