NASA/DLR Measurements from the DC8 of Aircraft Emissions and Contrails at Cruise

This presentation will describe the NDMAX/ECLIF flight campaign, which was jointly conducted by NASA and German Aerospace Center (DLR) to assess the potential of renewable jet fuels for mitigating aircraft climate impacts. Conducted between January 14 and February 3, 2018 from Ramstein Air Base in southwest Germany, the mission used the instrumented NASA DC-8 to sample exhaust and contrails from the DLR A320 "Advanced Technology Research Aircraft" (ATRA) as it burned either standard Jet A-1 or three different Jet A-1/biojet blends. Investigators from DLR, NASA, Max Planck-Institute of Chemistry, and the University of Oslo contributed to the DC-8 instrument payload, which included measurements of cloud microphysical properties, trace gases, water vapor and aerosol number, mass, size, volatility and composition. Similar measurements of ATRA emissions were made by the DLR, NASA, the Missouri S&T, Aerodyne, and the National Research Council, Canada during eight-hours of ground tests conducted to obtain data for further developing fuel-based, emission models. Seven separate DC-8/ATRA formation flights were conducted within temporary restricted airspace (TRAs) over northern Germany that involved flying race-track patterns at nominal 260, 320, and 380 flight levels and at 0.72, 0.76 and 0.80 Mach. Safe DC-8 sampling distances were calculated based on the ATRA weight, altitude and speed and ranged from 2.5 to 14 NM. In all, data were collected in over 1,000 individual wake-plume crossings during 33 hours of joint DC-8/ATRA operations. A six-hour DC-8 flight was also conducted over western Germany to sample exhaust plumes from commercial B737max and A320neo aircraft with new, low-emission LEAP engines to investigate links between soot emissions and contrail microphysics. The presentation will include details of DC-8 modifications, payload, hazard assessments, deployment planning, flight operations and research highlights.