Biofuels cut jet engine pollution, shows Nasa study

A study led by Nasa showed that use of biofuels in aircraft can slash carbon particle emissions by 70 per cent and also curtail the formation of contrails, which are adversely impacting the atmosphere. Generally, plant materials like halophyte and forest waste called camelina are used in making biofuels. Already, many airline companies like Virgin Atlantic and United Airlines, as well as the US Air Force, are using biofuels in flying a portion of their fleet. The Alternative Fuel Effects on Contrails and Cruise Emissions Study had Nasa and other partners from Germany and Canada conducting tests by trailing a DC-8 aircraft that used a mix of jet fuel and biofuel as a camelina oil derivative.

The tests were conducted between 2013 and 2014 with the research aircraft following the Nasa aircraft. Measurements taken during the observations on the carbon emissions from the exhaust and formation of contrails were analysed. The research has been published in Nature. The study makes specific mention of the formation of contrails resulting from the conjunction of hot emissions from aircraft engines and the cool air at high altitudes. Though contrails contain only water vapour and ice crystals, the problem can worsen when cirrus clouds are formed, which may upset the natural weather processes. Nasa will be continuing the study to assess the benefits of biofuels by testing for results on a QueSST, a supersonic X-plane.