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Optimal Propellers for a Small Hybrid Electric Fuel-Cell UAS

The use of small, electrically powered unmanned aerial systems are seeing widespread use in surveillance and reconnaissance roles. To overcome the low energy density of current battery systems and extend the endurance of small tactical UAS, hybrid electric fuel-cell systems are being investigated. This paper investigates propeller optimisation for a small hybrid electric fuel-cell UAS. Multi-objective optimisation is presented to display the possible couplings between an optimal propeller and motor for single-goal designs of both maximum aircraft endurance and maximum aircraft range. Additionally, Pareto fronts illustrate the tradeoffs between multiple competing design goals when optimising a fixed pitch propeller for a small tactical UAS.