Gulfstream SAF Testing Shows Contrail Emission Cuts

Gulfstream Aerospace has become the first business aviation company to complete a high-altitude flight-test campaign demonstrating the potential for 100% sustainable aviation fuel (SAF) to reduce contrail-forming particle emissions at altitudes up to 50,000 feet, the company said.

The campaign marked the first 100% SAF flight for the Gulfstream G800 and its Rolls-Royce Pearl 700 engine. Researchers paired the G800 with a specially modified G700 converted into a flying emissions-measurement laboratory. Flying in close formation, the two aircraft captured measurements of particulate matter and contrail-forming atmospheric characteristics at altitudes higher than those flown by most airliners, but typical for business jet missions.

Researchers compared jet-A, low-sulfur jet-A, and 100% hydroprocessed esters and fatty acids (HEFA) SAF, which contains no sulfur or aromatics. Preliminary results suggest a significant measurable reduction in the particulate emissions that contribute to contrail formation when operating on neat SAF.

“As aviation continues its work in optimizing environmental efficiencies, Gulfstream is focused on advancing solutions that deliver measurable impact today while shaping a more sustainable future for flight,” said Gulfstream president Mark Burns. “This campaign reflects our strategy to lead with advanced technology, real-world testing, and meaningful collaboration to better understand and reduce aviation’s environmental impact.”

Preparing for the campaign required months of work, including modifying the G700 cabin to integrate in-flight emissions instrumentation. Pilots trained in simulators to execute formation profiles designed to capture near-field emissions and contrail evolution several miles in-trail.

The research was conducted in collaboration with the FAA’s Center of Excellence (ASCENT), NASA, the German Aerospace Center (DLR), the Missouri University of Science and Technology, Aerodyne Research, Rolls-Royce, Montana Renewables, and World Fuel Services.

“This collaboration enabled these first-ever high-altitude 100% SAF emissions observations, allowing the team to operate safely and efficiently while maintaining the precision needed for accurate data collection,” said Rich Moore, NASA research scientist. “This real-world data is essential to improving our models and understanding aviation’s broader environmental impact.”

Gulfstream said its aircraft have flown more than 3.5 million nm on SAF blends to date. The campaign data will be shared with the broader aviation and atmospheric science communities to help refine analytical models and inform future fuel standards.

“Partnering with Gulfstream was an excellent opportunity that will help inform and quantify our efforts to mitigate the impacts of persistent contrails,” said Julie Marks, executive director of the FAA’s Office of Environment and Energy. “We appreciate the collaboration with industry as the FAA continues to evaluate how SAF may help reduce persistent contrails.”