During the civil aircraft flights, the pollutants in the air are inevitably inhaled in the components in the gas path of an aeroengine, forming dirt on the blades surfaces and edges. In order to analyze the attached contaminants, the online washing liquid was collected in the process of cleaning the two aircraft engines. The cleaning dirts morphology and components were respectively observed and analyzed by Scanning Electron Microscope (SEM) and Energy Dispersive Spectrometer (EDS) in order to obtain the main attached components and the particle size range to build a foundation for the simulation of the particle deposition. Dirt sediment were affected by the factors of the particles incident velocity and the compressors rotating speed that were explored through simulation experiments. The particles sediment rule can be attained on the blades surface, which can provide the theoretical basis for the aircraft online washing.