The most perverse thing about air travel is the inverse relationship between seat size and the up-sizing of passengers.

As the seats get smaller the effects of improved nutrition (as well as excessive nutrition) makes people grow larger, especially those who always occupy the adjacent seats when you are stuck in the middle.

This is not just because of the low cost airline revolution either, because it has been going on ever since the late 70s, when better engines meant Boeing 747s could be flown long distance with economy seats ten across the main deck rather than nine across.

And DC-10s went from eight across to nine across, inventing the dreaded middle block of five seats, so that hot meals could be routinely dropped on the person really stuck in the middle because the flight attendants couldn’t easily hand over the tray across two other passengers.

The latest version of this sort of bastardry is the changing of nine across seating in economy in Boeing 777s to ten across.

Everyone is doing it. The accountants love it because it greatly improves the CASK metric, or costs per seat per kilometre, and their secret metric, the UPPASK, or unhappy passenger per seat kilometre, which is clearly uppermost in the mind of most airlines and was probably invented by the Ryanair anti-christ Michael O’Leary.

But tomorrow Singapore Airlines flies its first ‘revised’ older model 777-300 to Sydney, and they haven’t done the dirty. The economy seats, with new in flight entertainment gadgets for the bored, stay at nine across.

Starting tomorrow, SQ's refurbished older 773s
Starting tomorrow, SQ's refurbished older 773s

A line has been drawn. Kneecaps and buttocks rule, OK.

The only downgrade in these jets is in business class. Tragic really. They have the wonderfully inaccurately termed ‘inclined lie flat beds’ of old (but with new colours and plasma screens and so forth) which means they can give people underwear wedgies if they gradually slide down the slope in fitful efforts to sleep.

And if you change to an A380 or the much newer Boeing 777-300ER at Changi you do get the truly flat, as in parallel to the floor, wide sleeper seat in business class.

And in the current economic situation, probably most of that cabin to yourself.

So for those of us who just want something civilised in economy class, let’s hope this is a reminder to all airlines with roomy nine across seats in 777s to leave them that way.

And also, not to even think of changing the current wide seats in A380 economy cabins to narrow little torture tubes just because the ‘beast’ is capable of lifting the extra load.