Abstract: To address the systematic impact of strong environmental uncertainties on the conceptual design of long-endurance fixed-wing unmanned aerial vehicles (UAVs) for Mars exploration, an energy-mass coupling model considering multiple uncertainty sources such as solar radiation, atmospheric density, and dust storm optical depth is established. By integrating direct and diffuse solar radiation fluxes on the Martian surface and incorporating key components including photovoltaic energy conversion, energy storage batteries, and thermal insulation consumption, a set of constraint inequalities defining the feasible region in terms of total mass and wing area is constructed. The sensitivity of the feasible region and cruise performance to optical depth, latitude, and areocentric longitude is systematically analyzed, and the feasibility of uninterrupted flight is evaluated based on low-Reynolds-number aerodynamic simulations. The results indicate that dust storm intensity has limited impact on the feasible region, while latitude and seasonal uncertainties exhibit significantly higher sensitivity. Due to the actual lift and drag characteristics at low Reynolds numbers being far lower than initial expectations, 24-hour uninterrupted flight is not achievable under current technological conditions, necessitating an hour-level flight strategy. Taking a design point of 10 kg mass and wing area, 24-hour flight can be achieved at low latitudes on the vernal equinox under clear conditions, whereas the flight duration reduces to about 11.2 hours at high latitudes on the winter solstice. This study provides a theoretical foundation for environmentally adaptive design and mission planning of fixed-wing solar-powered UAVs for Mars exploration.

Key words: Mars fixed-wing drone, uncertainty, radiation model, method for overall parameter design, parameter sensitivity