Within a year Travelport hopes to give every single flight a carbon rating, taking into account the plane, the type of fuel used, and other data points.

BBC: smokestack in Beijing

But the airline's chances of surviving in some form have been helped by a ruling by America's Federal Aviation Administration on July 30th, which downgraded Mexico's flight-safety rating a notch, owing to a lack of air-traffic controllers.

ECONOMIST: Mexican airlines