Think you're right, Giok. While they're there, I'll use them. There's also the question of alternatives - I could just as easily take the train up to Edinburgh, for example, but it's no cheaper than the plane. Make the planes more expensive and the alternatives cheaper, and we might see some changes.

Teribus, the drive has been for efficiency to save money on fuel bills, not out of any desire for greenness. And again, emissions are only improved by more efficient combustion for the same reason. Also, they're not really the "air industry" - the "air industry" are the airline operators, who understandably have been taking full advantage of the tax loophole on jet fuel to get as many planes in the air as possible.

Graham.