CO₂, NO_x, and Particle Emissions from Aircraft and Support Activities at a Regional Airport

The goal of this research was to quantify emissions of carbon dioxide (CO₂), nitrogen oxides (NO_x), particle number, and black carbon (BC) from in-use aircraft and related activity at a regional airport. Pollutant concentrations were measured adjacent to the airfield and passenger terminal at the Roanoke Regional Airport in Virginia. Observed NO_x emission indices (EIs) for jet-powered, commuter aircraft were generally lower than those contained in the International Civil Aviation Organization databank for both taxi (same as idle) and takeoff engine settings. NO_x EIs ranged from 1.9 to 3.7 g (kg fuel)⁻¹ across five types of aircraft during taxiing, whereas EIs were consistently higher, 8.8–20.6 g (kg fuel)⁻¹, during takeoff. Particle number EIs ranged from 1.4 × 10¹⁶ to 7.1 × 10¹⁶ (kg fuel)⁻¹ and were slightly higher in taxi mode than in takeoff mode for four of the five types of aircraft. Diurnal patterns in CO₂ and NO_x concentrations were influenced mainly by atmospheric conditions, while patterns in particle number concentrations were attributable mainly to patterns in aircraft activity. CO₂ and NO_x fluxes measured by eddy covariance were higher at the terminal than at the airfield and were lower than found in urban areas.