The pollution caused by planes and jets. Source: ThinkProgress

Aviation has a large impact on the environment. Emission of heat, particulates and polluting gases are some of the major problems it causes. These, in turn affect the global temperature.

A recent study has concluded that the usage of biofuels help power jet engines reduce particle emissions. Biofuels reduce the emissions as much as 50 to 70 percent. Biofuels are not only environmental friendly, but also economical.

The study published in journal Nature, comes as a result of a cooperative international research program led by NASA and involving agencies from Germany and Canada.

NASA’s HU-25C Guardian aircraft flies 250 meters behind the agency’s DC-8 aircraft on May 14, 2014, before it descends into the DC-8’s exhaust plumes to sample ice particles and engine emissions.
Credits: National Research Council of Canada

During flight tests near NASA’s Armstrong Flight Research Center, the agency collected data regarding several parameters. The parameters include, the effects of alternative fuels on engine performance, emissions and aircraft-generated contrails. The test series were part of the Alternative Fuel Effects on Contrails and Cruise Emissions Study, or ACCESS.

The hot aircraft engine exhaust on mixing with the cold air, produce contrails. It generally occurs at cruise altitudes several miles above Earth’s surface. They are primarily composed of water in the form of ice crystals.

Contrails create long-lasting, and sometimes extensive, clouds that would not normally form in the atmosphere. They have a great influence on the Earth’s atmosphere. Researchers are most interested in contrails for the above reasons.

The DC-8’s four engines burned either JP-8 jet fuel or a 50-50 blend of JP-8 and renewable alternative fuel of hydro processed esters and fatty acids produced from camelina plant oil.
Credits: NASA/SSAI Edward Winstead

NASA’s workhorse DC-8 flew as high as 40,000 feet, during the tests. Its four engines burned a 50-50 blend of aviation fuel and a renewable alternative fuel. The alternative fuel was composed of hydro processed esters and fatty acids produced from camelina plant oil. A trio of research aircraft took turns flying behind the DC-8 at distances ranging from 300 feet to more than 20 miles.

Sources from NASA said that its researchers are planning to continue these studies. They are keen to understand and demonstrate the potential benefits of replacing current fuels. It’s NASA’s goal to demonstrate biofuels on their proposed supersonic X-plane.