It is becoming increasingly clear that the Government's case for maintaining that a third runway can be built at Heathrow without increasing aircraft noise or exceeding permitted levels of air pollution is based on a series of fabrications.

Not only were the forecasts fiddled by reducing the number of very large aircraft using Heathrow from 20 to six per cent, also many of the large aircraft assumed to be using the airport in 2030 appear to have been an entirely fictitious 'green jumbo' that produces less noise than any known or projected type of aircraft.

Already, permitted EU air pollution levels are being exceeded in several places around Heathrow.

The extra traffic associated with T5 can hard-ly have helped this and either the construction of a third runway or the introduction of mixed mode operations should make the situation even worse.

I gather that a deputation has already alerted the EU to the fact that air pollution rules are being breached and that the Government does not seem to be doing anything about this.

All this seems to me to provide excellent grounds for challenging the validity of the Government's consultation document.

If that fails, it remains to document the real level of pollution resulting from a third runway and bring this to the attention of the EU.

They could even end up building a third runway and then discovering that they cannot use it.

JOHN MURPHY Camrose Avenue, Feltham.