This paper presents Ice Crystals particles trajectory simulations based on models representative of aircraft engines flying through realistic Ice Crystals clouds. The current study pursues of the work performed by Safran Aircraft Engines in the framework of the High Altitude Ice Crystals (HAIC) European research project. Results of the HAIC/High Ice Water Content (HIWC) projects flight campaigns are used to characterize the atmospheric environment in the Ice Crystals clouds. The present work benefits from the mixed-phased and glaciated particles trajectory modeling capabilities available in ONERA’s icing numerical tools. Simulations are run on two distinct geometries: a generic engine Inlet & Fan, and a generic Fan & Low Pressure Compressor. The first configuration allows the effects of centrifugation and fragmentation on particle concentrations at the engine’s primary flow inlet. The influence of particle size is also studied. The second geometry provides qualitative information on preferential accretion sites within the engine. Simulation results obtained for this configuration are consistent with experimental observations of the so-called plateau effect.