NASA is getting in on efforts to move toward a green future for commercial aviation. Scientific American reports that the space agency is giving millions to teams developing ultra-efficient, eco-friendly planes.

For several years, the airline industry has been experimenting with alternative fuels. Test flights have used everything from algae-based biofuels to cooking oil. New lighter, more aerodynamic passenger jets have increased fuel efficiency, and airlines are trying to retrofit old planes to make them more fuel efficient.

For airlines, the need for innovation is more about economics than the environment. The profitability of the industry is tied to oil prices. By some estimates, as much as one-third of an airline’s total operations budget is consumed by fuel costs.

The problem with NASA’s efforts is that the designs will be so radical that it will be at least 20 years before they take to the skies — but the early buzz is impressive. 

The project, dubbed N+3 because of its attempt to develop planes that could be used three generations into the future, seeks major changes to the way airplanes are made and fueled. The designs will be as much as 70 percent more fuel efficient than current passenger aircraft. They will emit 75 percent less nitrous oxide and be much quieter than current planes.

Another, less-hyped NASA project might have more immediate effects on pollution caused by commercial air travel.

Called N+2, this initiative seeks to cut fuel consumption of airplanes by as much as 50 percent between 2020 and 2025. If this ambitious but realizable goal is reached, nitrous oxide emissions would be cut by as much as 75 percent.

Lockheed plane design

An artist’s rendering depicts a Lockheed Martin future airplane design. (Photo: NASA)

The teams NASA is funding include designers who work for Boeing, GE Aviation and Lockheed Martin.

Meanwhile, Boeing has announced a project that could be ready to fly about the same time as NASA delivers its first project. Boeing has proposed a hybrid airplane that would run on electricity and could use clean biofuels instead of traditional jet fuel. A single-seat hybrid plane, built with funding from Boeing, has already had a successful test flight in England.

It will be years before this type of aircraft could take to the sky and even longer before commercial airlines start making hybrids part of their fleets. The safety concerns are too great to rush any of these innovations to market without extensive testing.

One completely emission-free airplane has already had a test flight, though the model is completely impractical for commercial airlines. The Solar Impulse project has produced a sun-powered plane that can fly with no fuel whatsoever. An around-the-world flight is on the calendar for the plane by the end of the year.

The flight would highlight one of the most attractive attributes of a sun-powered aircraft: It could fly indefinitely. That might seem like a pipe dream today, but it raises possibilities for airlines worried about fuel budgets and the prospect of offering ultra-long-haul flights without layovers. The main drawback is the speed possible with solar power. The first test flight went only about 35 mph.

Jay Dryer, who is directing the NASA aviation development programs, predicts that solar-powered airplanes will eventually be used for commercial flights. However, he also predicts that it would be at least 50 years this advance will become possible. 

With more and more people taking to the sky, fuel usage and emissions from jet engines will continue to increase. Some experts estimate that the total number of commercial fliers worldwide will double between 2015 and 2030.

Between NASA projects, alternative fuel tests and retrofitting projects, the airline industry will only get greener as manufacturers adopt the most successful trends into their operations. 

Related on MNN: