I doubt that in 30 years time the price of fuel will be less, what with more people using more cars and all of us chasing stocks of petro products. Not so much the fuel running out as us being outbid on it. Remember during the fuel strike a few years ago when fuel shot up to 65p per litre??? What is it now?
There must surely come a point in time when travelling to Mexico for a week in the sun will become so expensive that we give it up as an excessively expensive luxury. A bit like getting bladdered on a Friday night has already become.
Spending £70M on an airport seems (to me at least) a bit like buying up all the cigarette factories at a knock-down price in that it may seem a bargain in the short term but you are going to need to get a return from an ever shrinking and fragile market. How many pax do you need to fly to service a £70M expenditure?
I didn't take a holiday abroad this year for cost reasons and I'm a Cardiff pilot with Thomson.
Note. Thomson sized airlines spend the thick end of $500M per year on jet fuel.