Transient Aircraft Soot Emissions Indicate That Steady-State Measurements Likely Underestimate Real-World, Take-Off Emissions: Time-Varying Aircraft Take-Off Emissions Indices Measured at Los Angeles International Airport

Abstract

Verbatim from NASA NTRS. Not paraphrased, not summarized.

Aircraft engine emissions are unique among mobile pollution sources in that their impacts affect the local air quality near airports as well as upper tropospheric composition and climate over regional-to-hemispheric scales. Furthermore, air travel and its resulting emissions are expected to rebound from the recent COVID-related lows to increase dramatically over the next several decades. Given the multi-decade service lifetime of many commercial aircraft, it is critically important to quantitatively understand the real-world emissions coming from these engines in order to inform environmental assessment and modelling activities. Here, we present a detailed analysis of aircraft emissions during take-off operations at Los Angeles International Airport. The data were collected as part of the NASA Alternative Fuel Effects on Contrails and Cruise Emissions (ACCESS) project in May 2014, and the dataset is publicly available as described by Moore et al. [1]. In particular, we focus on the time-varying nature of the plume concentrations where clear differences in particle size and non-volatile particle fraction are observed during the early portion of the take-off plume relative to the later portion of the plume. We compare the transient emissions indices measured here to engine certification values in the International Civil Aviation Organization (ICAO) Emissions Databank, which suggests that steady-state measurements may underestimate the real-world, non-volatile particle emissions. The implications of this finding for modelling aircraft particle emissions will be discussed.

Authors

• Richard H. Moore Langley Research Center
• Michael A. Shook Langley Research Center
• Luke Ziemba Langley Research Center
• Joshua DiGang Langley Research Center
• Edward L. Winstead Science Systems and Applications (United States)
• Bastian Rauch German Aerospace Center
• Tina Jurkat-Witschas German Aerospace Center
• Kenneth L. Thornhill Science Systems & Applications, Inc.
• Matthew D. Brown Science Systems and Applications (United States)
• Ewan Crosbie Science Systems & Applications, Inc.
• Francesca Gallo Universities Space Research Association
• Carolyn Jordan National Institute of Aerospace
• Claire Robinson Science Systems & Applications, Inc.
• Kevin Sanchez Universities Space Research Association
• Taylor Shingler Langley Research Center
• Elizabeth B. Wiggins Universities Space Research Association
• Bruce Anderson Langley Research Center