Can Air Travel Ever Be Sustainable?

Flight is an especially tough form of transportation to clean up—but it may be possible.

BY SEAN CAPTAIN

Even miles out from an airport, the stink, noise, and sprawl attest to the heavy environmental toll that air travel imposes. Flight is carbon intensive and difficult to separate from dirty fuels. You can’t pack enough batteries into a plane to get it across even a U.S. state. And beyond CO2, other pollutants and those wispy exhaust contrails can potentially double heat trapping in the atmosphere.

That’s the bad news, but there is a surprising amount of good. Facing thin margins and fierce competition, airlines are obsessed with conserving energy. Fuel efficiency has improved about 80% since the 1950s, with at least 1.5% improvements continuing every year. There are also credible technologies—intermixed with some very optimistic predictions—to replace fossil fuels in both jet and piston engines. It will take clear thinking from engineers and judicious decisions by passengers to steer aviation toward sustainability.