[Air Pollutant Emission Inventory from LTO Cycles of Aircraft in the Beijing-Tianjin-Hebei Airport Group, China].

Based on the International Civil Aviation Organization's standard emission model, this survey collected the actual flight conditions of the nine airports in the Beijing-Tianjin-Hebei airport group, fully considered the impact of the height of the atmospheric mixed layer, and revised the operating time using the US Environmental Protection Agency method to accurately estimate the 2018-2019 shipping season (364 days) landing and take-off cycle (LTO) air pollutant emissions list for Beijing-Tianjin-Hebei airport group aircraft. The results show that the total emissions of NOx, CO, SO2, HC, and PM in the LTO cycle of the Beijing-Tianjin-Hebei airport group in the 2018-2019 season are 10720.5, 3972.2, 407.8, 508.0, and 53.7 t, respectively. Within these, the winter and spring season emissions are 4290.2, 1646.7, 168.3, 220.1, and 22.4 t, respectively; and the summer and autumn season emissions are 6430.3, 2325.5, 239.5, 287.9, and 31.3 t, respectively. From the perspective of spatial distribution, Beijing Capital Airport is the airport in the group with the largest amount of air pollutants discharged. Regarding time distribution, the highest peak is at 07:00-08:00, there is a medium-high emission level from 12:00-20:00, and the emissions are relatively low after 21:00. The aircraft emit more NOx and CO in the LTO cycle, with PM accounting for the least amount of emissions. The discharges of different pollutants under different working modes are significantly different. Of all the aircraft in the airport group, the B777 unit LTO discharges the most pollutants, that of the B737 is the least, and the B787 unit LTO circulation HC is the lowest.