Making air travel and its expected expansion sustainable will be immensely challenging. While aircraft are getting more efficient, it still takes a lot of fuel to fly. Though biofuels and other alternatives hold promise, large scale implementation will be a long way off. The issue is not that planes are inefficient. Per passenger mile traveled, airplanes are pretty good, especially on long distance flights.
The issue is that a lot of people and cargo are traveling long distances by air. This has great social benefits and it’s good for the economy. Unfortunately, it can be a relatively large portion of a traveler’s total carbon footprint. Exactly how much fuel is used on any specific trip depends on a lot of factors including the length of each leg of your flight, the type of plane and what class you fly. Because of the space taken up in an airplane for business and first class travel that could otherwise accommodate more economy seating, the per person fuel usage can be many times more in business and first class than economy. Also, each time a plane takes off it uses a lot of fuel, so longer flights are more efficient per mile. Obviously, the easiest way to reduce air travel emissions is to fly less. When you need to fly, fly economy class because your footprint is much lower than that of the people up front, even if you can afford the first class fare.
To mitigate your impacts when you do fly, buy carbon offsets. For those flying corporate and private jets – your impacts are excessive. If you care about the future you are leaving for your grandchildren, you should be supporting programs that factor in the cost fuel combustion on the environment so that system can get built for large scale carbon sequestration. Civil aviation (generally small propeller planes) has similar issues to private transportation and hobbies. People who are flying small planes should be aware of their impacts and should mitigate these impacts with carbon offsets.
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