Quotes of the Day

Let's start with an uncomfortable and increasingly important truth: flying is pretty tough on the environment. Sure, today's aircraft are some 70% more fuel efficient than planes operating in 1970. But passenger numbers are soaring: the industry expects to fly 2.2 billion people this year, 10% more than in 2005. The result? Aviation's share of global CO2 emissions, now around 2%, is expected to hit 3% by 2050.

Problem is, flying is often the only way to go. Four-fifths of airline-related emissions come from journeys over 1,500 km, for which there's no real alternative (Moscow to Beijing by bus, anyone?). But if flying simply can't be avoided, its environmental impact needn't be a write-off.

Consider seating arrangements. "The more people on a plane, the better," says Gehan Talwatte, managing director of London-based aviation consultancy Ascend. Legroom may be compromised during budget or charter flights, but squeezing more seats on board reduces each flier's share of an aircraft's fuel load and greenhouse-gas emissions. While a charter and a scheduled flight each burns around a ton of fuel traveling between London and Malaga, Spain, for example, charter planes can pack in around 16% more seats, lowering the fuel used per passenger by a similar amount.

Find taking connecting flights to be a waste of time? Flying direct is more than just convenient. With the intense fuel burn of take-off and landing cycles generating a big portion of a flight's emissions, changing planes can worsen an overall journey's environmental impact. According to Ascend, a direct chartered flight from London to Goa, India—routinely carrying extra seats—can use 60% less fuel per seat than a scheduled service that requires passengers to transfer. So, with guilt alleviated, you're ready for that vacation: seats aboard charter flights are available from a host of operators (try www.tui.com or www.mytravel.com for more details). Now if only we could just cut delays.

• Adam Smith
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