This from the BBC
Virgin Atlantic plan to save fuel
Sir Richard Branson has called on the industry to cut carbon output
Sir Richard Branson's Virgin Atlantic is to conduct a trial using 13 of its planes which could cut aviation fuel use and slash carbon dioxide emissions.
By towing its Boeing 747-400 aircraft to take-off areas at London airports during December it said it could save up to two tonnes of fuel per flight.
Aircraft will be towed to Heathrow and Gatwick runways to cut fuel burning.
Virgin said a reduction of 120,000 tonnes in carbon emissions a year could be made if extended across its fleet.
'Starting grids'
It is hoped to reduce the time engines are running before taking off to about 10 minutes.
"Towing aircraft from a stand substantially reduces the amount of time they need to taxi with their engines running and reduces the time spent queuing before take-off," said Virgin Atlantic spokesman Paul Charles.
Virgin Atlantic is working alongside airport operator BAA and National Air Traffic Services (Nats) during the trial, with a longer run-out expected in the first quarter of 2007.
Aircraft will be towed from their stand at the airport to so-called "starting grids" - which are holding areas, close to a runway, consisting of several parking bays for aircraft.
It means that aircraft can be towed closer to a runway before take-off.
Teams from Virgin Atlantic are also holding talks with the international airports in San Francisco and Los Angeles, as well as JF Kennedy airport in New York, about the timing of similar trials.
Greenhouse gases
Virgin Atlantic is half owned by Sir Richard Branson and the other half by Singapore Airlines. The other aircraft in the fleet are five Airbus A340-300, and 17 Airbus A340-600.
Airlines are in the spotlight over the amount of carbon emissions which the industry is producing following falling fares and the growth of low-cost operators..
Aircraft are one of the fastest-growing sources of greenhouse gases and environmentalists are calling on the government to take action to reduce their output of carbon.
Carbon dioxide emissions from aviation doubled during the 1990s while those from the rest of the economy fell. Currently, aircraft produce about 5.5% of UK emissions.
In September Sir Richard said that up to 25% of the world's aviation carbon dioxide emissions could be cut if airlines, airports and governments worked together.
He has also pledged Virgin Group profits worth $3bn (£1.6bn) towards renewable energy initiatives.