Aircraft

Virgin Atlantic, Boeing and General Electric are within weeks of selecting the biofuel for a flight demonstration in the UK early next year. "We are working towards a downselect very shortly," says Tim Held, GE Aviation fuels specialist.

"There are three leading candidates, all with different sources and processes," says Held. Producing jet fuel from biomass using the Fisher-Tropsch process is not one of them, he says. "It's not on the list because it's been done."

Ground testing of the chosen fuel in a development engine at GE is expected to begin in October-November, says Held. The limited flight-test programme will involve burning biofuel in one GE CF6-80C2 engine on a Virgin Boeing 747-400.

The demonstration will require special permission from the US Federal Aviation Administration, he says. The flights will not be in revenue service and will involve an aircraft that is about to go into heavy maintenance. "There will be no changes to the aircraft other than to fill the tank," Held says.