it's 5 years most lenders look for a return on their investment
I'm not sure what was meant by this - for a personal loan, that would be normal (they only relatively recently started going to 7). This would be an investment, not a loan - and any infrastructure of this nature would have much longer times than that.
Also, if the airport is worth £800m, then in five years time, it will still be a valuable asset, whatever they do to it - some of the buildings and surfaces will deteriorate, but the funamentals won't change.
I'd be more interested in learning if, given recent talk of trying to bring HS2 to Scotland sooner, rather than later - and starting with a link between Glasgow and Edinburgh - whether that would serve either airport, or indeed both. Realistically, Glasgow airport just needs to get its fixed link 'back on track'. A high speed station underneath the terminal at EDI would give incredibly quick times to both cities, and much more useful than those - ok, I won't mention the t word, probably too sore a point!
