Richard Branson yesterday revealed Virgin Atlantic is just months away from a test flight that will see one its Boeing 747s run on biofuels for the first time.

According to reports from Reuters, Branson said that the company would undertake a test flight "early next year" using one of the renewable fuels it has developed through the group's new Virgin Fuels subsidiary.

The flight, which will be conducted without passengers, would be the first of its kind and see the company pre-empt plans by Air New Zealand to undertake a test flight using a combination fuel of biofuel and kerosene in late 2008.

Speaking at a Mortgage Bankers Association meeting in Boston, Branson said that the company had encountered difficulties using ethanol to power flights as it freezes above 15,000 feet and was instead investigating using butanol, a biofuel with similar properties to gasoline, for aviation.

The flight will represent a major milestone for Virgin Fuels, which Branson set up last year with a pledge to invest all the profit over the next decade from his stake in Virgin's airline and rail businesses in tackling global warming.

Environmentalists welcomed the news but remained sceptical about the potential green benefits that can be attained in the medium term from the new fuels.

"The news is great in the sense that the aviation industry is facing up to the problem of climate change and seeking solutions," said Richard Dyer, aviation campaigner at Friends of the Earth. "But biofuels are not a solution on their own. There are major technical problems still to overcome with biofuels freezing at high altitudes."

He added that projects to develop aviation biofuel also did little to alleviate the well-documented problems associated with biofuels such as increased pressure on agricultural land and questions over whether they genuinely deliver carbon savings when the full development life cycle is accounted for.

In related news, Airbus yesterday delivered the first A380 to Singapore Airlines amidst claims the new "Super Jumbo" boasts significant environmental benefits.

Airbus said the new aircraft was "greener, cleaner, quieter and smarter" and would deliver an "unmatched fuel efficiency" of less than three litres per passenger per 100km.