At the just concluded AirVenture 2013 air show in Oshkosh, WI, a first-ever dual fuel compressed natural gas (CNG) powered aircraft was introduced by Aviat Aircraft Inc. and the Minneapolis-based Aviation Foundation of America Inc.
The Aviat Husky CNG was billed as the world's first dual fuel, piston powered aircraft to operate on both CNG and aviation gasoline. The plane flew more than 1,000 miles en route from Aviat's Afton, WY, headquarters to the AirVenture show.
Aviat fitted its standard Husky A1-C with a CNG fuel tank in addition to its standard 50-gallon aviation gasoline tanks to fuel its 200-hp, four cylinder Lycoming aircraft engine with a 143 mph cruising speed. The range, or flight endurance, is about seven hours operating at a 65% power setting.
Modifications to the standard gasoline-power Husky aircraft include the CNG tank and fueling system and new pistons in the Lycoming engine to increase the compression ratio. The CNG dual fuel system added between $12,000 and $15,000 to the price of the plane.
Aviat President Stu Horn called his company's latest innovation "a remarkable proof-of-concept airplane." Horn acknowledged the company met some challenges in converting a standard aircraft model into a dual fuel configuration, but "the performance and ease of operations have exceeded our expectations."
Greg Herrick, president of the Aviation Foundation, approached Aviat with the idea of demonstrating the use of natural gas in general aviation aircraft. Herrick noted some of the advantages of using CNG include fuel cost savings, cleaner burning fuel operations and no lead emissions. He thinks that CNG can be "readily applied" to a variety of piston-powered aircraft.
Generally, CNG sells for about 80% less than aviation gasoline, which is averaging about $6/gallon. CNG has no lead in it, while the lead content in aviation gasoline is getting to be a major issue, according to Herrick. CNG typically burns 138 octane and can provide enhanced performance compared to the 100 octane aviation gasoline.
The prospect attracting the Aviation Foundation is for CNG dual fuel aircraft to help reduce the overall cost of flying and flight instruction. CNG fueling infrastructure longer term would need to be added at airports, but for now removable fuel tanks can be taken to nearby CNG fueling facilities used for ground transportation, Aviat officials noted at the air show.
Earlier this year, Royal Dutch Shell plc and Qatar Petroleum teamed up with Qatar Airways to produce a natural gas-based aviation jet fuel, which was used on a commercial jetliner from Qatar (see Daily GPI, Jan. 15). A Qatar Airways Airbus A340-600 plane flew outbound from Doha International Airport to London Heathrow using the gas-to-liquids (GTL) jet fuel, which was blended with GTL kerosene and conventional oil-derived jet fuel at the Pearl GTL facility in Qatar.