Overview of the 2023 Boeing ecoDemonstrator Emissions Flight Test
RICHARD MOORE, Steven Baughcum, Tiziana Braeuer, Matthew Brown, Andrew Freedman, Francesca Gallo, William M Griffin, Francisco Guzman, Jennifer Klettlinger, Richard Miake-Lye, Benjamin A. Nault, Daniel Sauer, Michael Shook, Gregory Smallwood, Christiane Voigt, Phil Whitefield, Elizabeth Wiggins, Edward Winstead, Luke Ziemba, 2023 Boeing ecoDemonstrator Explorer Science Team, NASA
Abstract Number: 575
Working Group: Aerosols, Clouds and Climate
Abstract
Aircraft engines emit sub-30 nm soot particles and nucleation mode droplets that have impacts on the local air quality near airports as well as in the formation of climate-altering contrail cirrus clouds. It is currently thought that the radiative forcing from these contrail cirrus today is of similar magnitude to that from the cumulative carbon dioxide emissions since the dawn of the jet age. Sustainable aviation fuels (SAF) are a promising pathway for helping to meet the Biden Administration’s goal of net-zero aviation carbon dioxide emissions by 2050. Replacement of older airplanes with current production airplane/engine technology and SAFs are likely to be 100% of the solution through 2030 and still play a big role even in 2050. NASA-funded research has shown that SAFs have important co-benefits for reducing engine particle emissions, and the improvement can be even greater when pairing SAFs with advanced, low-emitting lean burn engine technology.
Recently, NASA, Boeing, GE Aerospace, United, DLR, Aerodyne Research, and other national and international partners measured the particle emissions and contrail properties behind a Boeing ecoDemonstrator Explorer 737-10 burning both conventional Jet A fuel and 100% SAF. While dramatic soot particle number emissions reductions were apparent, large numbers of volatile nucleation mode particles were measured even after carefully controlling the fuel composition to minimize sulfur content. The implications of these nucleation mode particles as potential seeds for contrail ice crystals will be discussed.