Latest Boeing EcoDemonstrator Studies SAF Use on Contrails Written 6 November 2023

Aviation International News reports that while studies have determined an 85% reduction of carbon emissions from sustainable aviation fuel (SAF), the contrails produced by SAF have not been studied to determine how they differ from those generated by kerosene. To that end, The Boeing Company has partnered with United Airlines and NASA “to study the phenomenon with its latest EcoDemonstrator aircraft.” In early October, Boeing “began flying a CFM LEAP-1B-powered 737 MAX 10 destined for United Airlines on 100 percent sustainable aviation fuel (SAF) and conventional fuel in separate tanks, alternating the fuels during testing.” Studying multiple fuels “with the same engine allows researchers to differentiate the emissions reductions resulting from advanced engine technology from those resulting from advanced jet fuel chemistry.” Although the sample “of results from last month’s testing remains too small to draw any conclusions, researchers from Boeing, NASA, GE Aerospace, and German aerospace research center DLR expressed optimism over the observations from the first three weeks of trials.” DLR Research Team Lead Christine Voigt explained some of the science behind the effect of SAF on contrail production and said, “These sustainable aviation fuels have a lower aromatic content and these are precursors to the soot particle emissions and the soot particles are the precursors for the ice crystals and contrails. Science tells us that warming from contrails might be as large as the warming from CO2 emissions.” 
Full Story (Aviation International News)