Boeing, NASA, and United Airlines have come together to conduct in-flight tests to measure the impact of sustainable aviation fuel (SAF) on contrails and non-carbon emissions, as well as to assess its role in reducing the climate impact of aviation. This collaboration underscores a collective commitment to understanding how innovative fuels, engine technology, and other advancements can mitigate atmospheric warming.
Boeing’s “ecoDemonstrator Explorer,” a 737-10 aircraft designated for United Airlines, will play a central role in the testing. The aircraft will be fueled with a combination of 100% SAF and traditional jet fuel stored in separate tanks, with alternate fuels being used during the trials. Flying in the wake of this commercial jet, NASA’s DC-8 Airborne Science Lab will meticulously measure emissions produced by each fuel type and the formation of contrail ice particles. In addition, NASA’s satellites will capture crucial images of contrail development as part of the testing process.
The primary objective of this research endeavor is to gain insights into how advanced fuels, engine combustor designs, and other cutting-edge technologies may contribute to reducing atmospheric warming. Specifically, the tests will focus on how SAF impacts the characteristics of contrails, the persistent condensation trails formed when aircraft traverse cold, humid air. While the full implications of contrails are not yet fully understood, some studies have suggested that certain types of contrails might contribute to trapping heat in the Earth’s atmosphere.
World Energy, based in Paramount, California, is supplying the SAF for these pivotal tests, with additional support coming from the U.S. Federal Aviation Administration (FAA), which is providing funding through the ASCENT Center of Excellence. GE Aerospace is contributing its technical expertise and project funding, while the German Aerospace Center (Deutsches Zentrum für Luft- und Raumfahrt or DLR) is offering the valuable insights of its experts and instrumentation.
This initiative marks the latest phase in an extensive multi-year collaboration between Boeing and NASA, dedicated to exploring how SAF can effectively reduce emissions and usher in a host of other environmental benefits. In comparison to traditional jet fuel, SAF, which can be produced from a range of sustainably sourced feedstocks, has the potential to reduce emissions by up to 85% over the course of its life cycle, making it a pivotal player in the quest to reduce aviation-related carbon dioxide emissions over the next three decades. SAF also produces less soot, offering the prospect of improved air quality near airports.
Boeing’s Chief Sustainability Officer, Chris Raymond, expressed his enthusiasm for the partnership, stating, “We’ve solved hard problems before, and if we continue to take meaningful actions, I’m confident we’ll achieve a more sustainable aerospace future, together.”
Rich Wahls, NASA mission integration manager for the Sustainable Flight National Partnership, emphasized the significance of flight testing in comprehending the impact of sustainable aerospace innovations on contrails and climate. He stated, “This is why we’re bringing NASA’s DC-8 to bear on this collaboration, where the valuable flight data will improve our predictive models.”
Lauren Riley, Chief Sustainability Officer at United, underscored the potential of the collaboration, saying, “This collaboration between Boeing, NASA, and United has the potential to not only help us better understand contrails but to provide the full scope of what our transition to SAF can provide beyond greenhouse-gas reductions.”
Mohamed Ali, Vice President of Engineering at GE Aerospace, expressed the company’s pride in supporting this groundbreaking research collaboration, aiming to deepen the scientific understanding of SAF’s impact on emissions and foster a more sustainable future for aviation.
Markus Fischer, DLR Divisional Board Member for Aeronautics, emphasized the need for international cooperation in achieving climate-compatible aviation and highlighted the extensive experience of the German Aerospace Center in researching the climate impact of the entire aviation system. Fischer said, “The continuation of transatlantic cooperation now finds a new summit and underlines the international commitment to reduce the climate impact from aviation’s CO2 and non-CO2 effects.”
The 737-10, part of Boeing’s single-aisle 737 MAX family, represents a significant stride in reducing fuel consumption and emissions, with a 20% improvement compared to the aircraft it replaces. This collaborative effort stands as a testament to the aviation industry’s dedication to reducing its environmental footprint and striving for a more sustainable future.
