The aim of this paper is to analyze different aspects of microphysical properties of mixed phase clouds, considering also the processes that are contributing to their formation. ATMOSLAB airborne laboratory, equipped with CAPS – Cloud, Aerosol and Precipitation Spectrometer sensors system was exploited to perform three flight research missions focused on cloud microphysics. For this purpose, there was analyzed the variation of 4 major parameters with high influence the cold clouds lifecycle (temperature, pressure, number concentration, effective diameter and 2D images of droplets and ice crystals) and was highlighted the occurrence of nucleation, accretion and droplet coalescence in cirrus and cirrostratus clouds.