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Safety concerns mean that biofuel will not be permitted for aircraft in passenger service for at least five years, despite the first flight yesterday of a jet partly powered by coconut oil (Ben Webster writes).

The 350-seat Virgin Atlantic Boeing 747 flew from Heathrow to Amsterdam with five people on board. However, only 5 per cent of the fuel used was biofuel. Fears that the biofuel might freeze or cause the engine to underperform meant that it was restricted to supplying one engine partly. The other three engines ran on normal aviation fuel and were isolated from the tank that contained 20 per cent biofuel and 80 per cent normal fuel.

GE, the American aircraft engine manufacturer taking part in the test, had run ground tests with the biofuel and found that it did not freeze until minus 51C (-60F), within the safety specification that aviation fuel should not freeze until it reached minus 47C.

Dave Daggett, Boeing’s project manager for alternative fuels, said biofuel was unlikely to be certified for passenger service before 2013.

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