Gust Behaviour and Envelope Build-Up Process for Fixed-Wing Multi-Mission Remotely Piloted Aircraft

The study of aircraft gust behaviour is essential in aerodynamic and structural design and analysis, as well as in airworthiness certification. The particularities of fixed-wing Remotely Piloted Aircraft (RPA) demand a specific study of gust effects on these vehicles and their implications in RPA design and operation. The research presented here addresses the investigation of gust behaviour of RPA within the frame of conceptual design through three complementary approaches, which are respectively based on the assessment of gust and manoeuvring envelopes of RPA, the modelisation of multi-mission flight profiles of RPA towards the evaluation of the variations in gust load factor along the mission, and the analysis of the interaction of RPA conceptual design parameters with gust behaviour. These approaches are applied to various case studies, providing several key insights into the gust behaviour characteristics of RPA. These include the assessment of the operational conditions in which gust-induced stall may occur and the way in which they interact with typical mission conditions of RPA, the evaluation of the impact of mission parameters in RPA gust response along with the capability of identifying the most critical gust load factor condition for the set of considered design missions, and the ways in which undesirable gust effects may be mitigated in the conceptual design stage through the change in overall RPA design parameters.