Characterization analysis of particles emitted from aircraft using positive matrix factorization

In order to characterize particles emitted from aircraft, we analyzed the elemental composition information of particles collected from aircraft using positive matrix factorization (PMF). The factor profile and source contribution were deduced based on PMF analysis with five factors and 30 random starting points. Factor 1 contains particles derived from engine oil. Factor 2 contains particles originating from the friction between the runway surface and the tire. Factor 3 contains particles deposited on the runway surface, mainly composed of soil components. Factor 4 contains particles derived from the turbine blade. Factor 5 contains particles derived from plant combustion and particles scattered during landing. Engine reversers accounted for more than 85% of the element total value with factor 2, factor 4, and factor 5. The carbon disc brakes had different main factors depending on the sample. For the tire grooves, factor 2 and factor 3 accounted for the majority of the element total value. The PMF analysis revealed that the particles collected from aircraft contained elements with different modes of generation. In addition, it was found that particles derived from plant combustion, which are presumed to have little relevance to particles emitted from aircraft, were included in the particles collected from the engine reverser, carbon disc brakes, and tire grooves.