American Airlines on Thursday turned an idea dreamt up by Sir Keith Mills in 1988 into $1bn of much-needed liquidity. The news that it had sold forward its air miles for $1bn to Citigroup, together with a new loan facility and a $1.6bn sale-and-leaseback commitment, sent the carrier’s share price skyward. The stock rose by as much as 25 per cent at one point. Investors can perhaps be forgiven their overreaction to this mildly good news considering that American Airlines has only turned a net profit twice this decade.

High fuel costs and the recession have forced airlines everywhere to look to their loyalty schemes as a potential source of funds: Delta did it last year with American Express. Still, they would rather not. The truth is that miles programmes are so profitable that airlines try their darndest not to reveal the underlying numbers. Qantas, for example, considered a part flotation of its frequent flyer business in the dark months of last year. Even though markets have brightened, that idea is now “indefinitely off”.