The world is seeing radical series of tests in flight to find alternatives to fossil fuels. So much of an airline’s costs are fuel driven, you can expect to see these tests monitored closely. The USAF is deep into its own bio-fuels tests and pleased so far. EADS is doing equally important tests with bio-fuels. Boeing is also busy with experiments.
But how about flying without any fuel whatsoever? Fantasy? Maybe not – its been done, though any commercial application is a long way off. But here’s an interesting read – GoodbyeFuelWorld.