NASA Examines Alternate Jet Fuels through Research Flights

Alternate fuel sources, including bio-fuels, are currently being tested by several airlines, most predominately by Sir Richard Branson’s Virgin Airlines. As this trend toward alternate fuels for airplanes continues, NASA researchers have begun to study the effects of alternate biofuel on engine performance, emissions and aircraft-generated contrails at altitude.

To perform their investigation of the viability of biofuels, and their potential impact on the environment, NASA is using DC-8 “flying laboratory” to conduct their test flights and gather information. The fuel used during test will be conventional aviation JP-8 jet fuel, or a 50-50 blend of JP-8 and an alternative biofuel made of hydroprocessed esters and fatty acids that come from camelina plants.

The research program is known as the Alternative Fuel Effects on Contrails and Cruise Emissions, or ACCESS for short. During the test flights, the aircraft will fly at altitudes up to 40,000. As the bio-fuels are burned in the engines of the DC-8, a chase plane, in the form of a NASA Falcon HU-25 aircraft, trails behind at various distances gathering data by sampling the exhaust with over a dozen external sensors and instruments.

“We believe this study will improve understanding of contrails formation and quantify potential benefits of renewable alternate fuels in terms of aviation’s impact on the environment,” said Ruben Del Rosario, manager of NASA’s Fixed Wing Project.

In addition to the NASA DC-8, NASA hopes to have opportunities to trail some commercial aircraft, in coordination with air traffic controllers, ad tak samples of their exhaust emissions as well. For reasons of public safety, these tests will be performed at a distance of at least 10 miles in trail.