Aerion Plans For 100 Percent Biofuel on AS2

Aerion Corp, which expects to begin flight testing its supersonic AS2 business jet in 2023, plans for the $120 million aircraft to be able run on pure biofuel, as well as the currently mandated jet-A blends that are seeing increasing use in commercial and business aviation.

According to the Business Aviation Guide to the Use of Sustainable Alternative Jet Fuel (SAJF), published last year by a consortium of industry organizations including GAMA, NATA, IBAC, NBAA and EBAA, the blend limits are to ensure the appropriate level of compatibility with the aircraft fueling systems, mainly due to ensuring a minimum level of aromatics, which are necessary to maintain the seals in the systems. “The question regarding aromatics and fuel seal performance is at the heart of SAJF operational compatibility,” said Gene Holloway, the airframer’s vice president for environmental responsibility. “The aromatic compounds found in traditional or blended Jet A/A1 fuel encourage the necessary seal expansion for engine/fuel system operation.

Last October Aerion and GE unveiled the engine program that was selected to power the AS2, and according to Holloway, advances in the material engineering now being used in new engines will render that concern a non-issue. “From a technical standpoint, we don’t see any obstacles at this time,” Holloway told AIN. “The modern materials used in today’s seals do not require aromatics to promote proper sealing. Our engine, the GE Affinity, incorporates seals that allow for 100 percent biofuels.”

SAJF is slowly being embraced by the aviation industry for its environmental benefits. At a recent Wings Club event in New York, Aerion CEO Tom Vice noted that the use of biofuels will reduce its aircraft emissions by at least 40 percent. A recent report from the Commercial Aviation Alternative Fuels Initiative (CAAFI) noted that SAJF use also resulted in a reduction in sulfur oxide and particulate matter, and a 15 to 25 percent decrease in carbon monoxide and unburnt hydrocarbons.

Aside from those environmental considerations, Holloway pointed out other benefits which would derive from the use of pure sustainable fuel. SAJF has a significantly lower freezing point than standard jet fuel, which is important for sustained operations at high altitude, and it has an energy density that is two-to-three percent greater than that of traditional petroleum-based jet-A, for improved operational efficiency and extended range.

Currently, the per-gallon cost of biofuel is on average six times that of jet-A, but Aerion expects that differential will drop considerably as production of sustainable alternative jet fuels (SAJF) ramps up. “The cost of biofuel varies significantly today based upon the feed stock and process used,” said Holloway. “Aerion is tracking multiple biofuels with slightly varying chemical properties and created from several feedstocks, because we understand that as biofuel becomes more available worldwide, significant amounts will be produced locally from regionally available feedstocks.”