Turboprop aircraft performance response to various environmental conditions

This study evaluated aircraft performance response to various environmental conditions encountered during night. These conditions included clear air, ice only, mixed phase, and supercooled drops, Supercooled drops consisting of cloud, drizzle, and rain sizes were the main focus of this study, Aircraft response was quantified by rates of change in aircraft climb capability, drag coefficient, and lift ol er drag ratio, The aircraft performance parameters were compared to an environmental hydrometeor parameter quantifying the environmental conditions, Results show that encounters with supercooled drizzle drops (SCDD) resulted in maximum rates of performance degradation, Encounters with supercooled cloud and rain-sized drops resulted in minor to low rates of performance degradation, whereas encounters with supercooled drops in low ice particle concentrations resulted in only minor rates of degradation, In addition, aircraft response to high ice particle concentrations, in low liquid water, following an SCDD encounter, resulted in rapid performance recovery, The results presented herein show a strong relationship between aircraft response and an environmental parameter utilizing a weighted volume diameter and liquid water content, The results suggest that the most severe icing is actually caused by SCDD as opposed to freezing rain.