The aircraft took off from Denver International Airport and climbed to 39,000 feet, and during the flight the onboard team collected data on the performance of the fuel during several manoeuvres including taxi, take-off, climb, cruise, auxiliary power unit start, descent and approach.
Unlike the Qatar Airways synthetic fuel flight conducted last October (see story), which used a 50/50 blend in one engine of a four-engined A340-600, no passengers were onboard. A team of 19 engineers and observers took part in the United flight, led by the airline’s Managing Director, Captain Joseph Burns.
“This flight confirms our assumptions about how this fuel performs on a commercial aircraft and is a next step in our effort to stimulate competition in the aviation fuel supply chain, promote energy security, environmental benefits and the creation of green jobs,” said Joseph Kolshak, United Airlines, Senior Vice President of Operations. “United continues to support the use of alternative fuels, and we urge the US government and the investment community to further support critical energy opportunities.”
United was one of 13 international and domestic carriers that signed a Memorandum of Understanding last December with Rentech over potential future supplies of the company’s RenJet fuel (see story).
The synthetic jet fuel – derived from coal or petroleum coke, rather than natural gas – would be produced from a proposed new facility in Natchez, Mississippi, and the airlines involved would take the entire production of RenJet fuel, estimated at 250 million gallons per year.
Synthetic fuel blends are currently the only alternative fuels certified for commercial aviation use, but aside from cleaner burning properties have limited environmental benefits in terms of CO2 emissions because of the energy-intensive Fischer-Tropsch production process involved, although biomass rather than fossil-based sources can be used to lower the carbon footprint.
However, Rentech intends to capture all the CO2 produced at the Natchez facility and sell it to an oil recovery company, Denbury, who would use it to produce otherwise unrecoverable oil at Denbury’s Cranfield oil field in Southwest Mississippi, as well as at the company’s oil fields within the greater Gulf Coast area. The Cranfield oil field is currently hosting a US Department of Energy (DOE) sponsored carbon dioxide sequestration project that claims to be the first in the US to inject more than 1 million tons of carbon dioxide into an underground rock formation, followed by additional injections into the saline portion of the reservoir, more than 10,000 feet below the surface.
According to Rentech, as concluded in a study conducted by the DOE National Energy Technology Laboratory, this would enable the fuels produced at the Natchez facility to have a life-cycle carbon footprint lower than that of petroleum-derived fuels.
Commenting on the United validation flight, Rentech President and CEO D. Hunt Ramsbottom said the flight was a significant step forward for the commercial aviation industry. “We are proud to collaborate with United Airlines to demonstrate the viability of certified synthetic jet fuel that delivers on performance and safety expectations required by commercial airlines, along with environmental benefits that exceed that of conventional jet fuel.”
CORRECTION POSTED MAY 13:
Qatar Airways operated an A340-600 on a revenue flight from LGW to DOH on October 12 using a 50/50 GTL fuel blend on ALL FOUR engines, not one as mentioned in the article. (For more information go to http://www.qatarairways.com/global/en/newsroom/archive/press-release-12Oct09-2.html)