The Government's environmental and economic case for expansion at Heathrow has been exposed as 'pure fantasy' by independent research published by the House of Commons Library, it was claimed today.
Transport secretary Geoff Hoon said only low emission planes would be allowed to use the new runway when he gave the go-ahead to a third runway last month.
But researchers at the impartial House of Commons Library found that 'aircraft designs do not at the moment incorporate many of the features highlighted by the secretary of state'.
"Unless there are some very rapid improvements in technology, it will be some time before more environmentally friendly commercial aircraft are in widespread operation," they said.
The research also casts doubt on the GovernmentÕs economic arguments, according to campaigners.
It states the Department for Transport's estimate of £8.2 billion worth of benefits to the economy over 70 years 'does not account for various factors' that could slash the benefits to £1.5 billion or less.
Its economic model relied on projections from the 2008 spring budget, researchers found, rather than the more pessimistic autumn pre-budget report that reflected the impact of the credit crunch.
The recession may permanently subdue demand for air travel, they added.
Geraldine Nicholson, chairman of NoTRAG (No Third Runway Action Group), said, "This is a damming indictment of the Government's position. The House of Commons Library researchers are confirming what we have always known that Geoff Hoon's 'green planes' don't exist.
"How much more misery should local people be required to go through before the Government admits that its plans for a third runway are pure fantasy?"