With the rising price of fuel and more stringent emissions regulations, there is a strong need for the aviation industry to begin taking steps to earn its green wings. It's not surprising therefore that biofuel was one of the hot topics at this week's Paris Air Show with both Boeing's 747-8 and Gulfstream's G450 business jet making the trip across the Atlantic on biofuel blends. The G450 flew in from Morristown, New Jersey, after a seven hour flight in which one of its Rolls-Royce engines was powered by a 50/50 blend of Honeywell Green Jet Fuel and petroleum-based jet fuel.

It's estimated that this use of biofuel saved 5.5 metric tonnes (6 tons) of carbon, a quarter of the average annual carbon emissions per person in the U.S, and half that in UK.

Honeywell's biofuel is derived from camelina, a dedicated energy crop that grows in rotation with wheat, which reduces competition with the food market. According to Honeywell, the biofuel offers up to an 85 percent reduction in net emissions compared to petroleum-based fuels. Additionally, it is manufactured using the same hydro-processing technology already used for the manufacture of today's transportation fuels, and can be mixed with petroleum-based fuel. Furthermore, tests have shown that it can be used for military or commercial applications without need for aircraft or engine modification.

The initial technology was driven by a 2007 contract from the U.S. Defense Advanced Research Projects Agency (DARPA) to produce renewable military jet fuel. Honeywell has experimented with biofuels made from camelina, jatropha and algae in sixteen biofuel test flights so far, and have produced more than 700,000 U.S. gallons (264,979 liters) of Honeywell Green Jet Fuel to date. The feedstock for the transatlantic flight was grown and harvested by Sustainable Oils, a U.S.-based producer of camelina-based technology.

"Gulfstream is committed to achieving business aviation's ambitious goals on emissions reductions," said Pres Henne, senior vice president, Programs, Engineering and Test for Gulfstream. "These include carbon neutral growth by 2020 and a reduction in total carbon emissions of 50 percent by 2050 relative to 2005."

Honeywell is also tackling its environmental impact on more than one front. Precision navigation and landing systems combined with improved systems for air traffic control reduce flight times and minimize airport delays, while increasing efficiency and safety and reducing carbon footprint. Planes can fly nearer to one another and land more efficiently without compromising on safety. They say fuel savings of up to US$100,000 per year per aircraft are possible through a greater ease to changing flight paths, and additionally are working on developing next generation GPS satellite air traffic management.

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