A procedure and supporting computer code for the prediction of noise that radiates from small, vertical lift UAV aircraft is proposed. The resulting building block procedure is theoretically based but is verified experimentally at several output stages. Noise source models for rotors, lift-fans, engines etc. are developed and validated through specially designed experiments and stored in a component digital library. For a given small lifting UAV configuration, these noise source models are combined into a hemispheric representation of the total radiated noise. The total radiated field is governed by the operating state of the vehicle as described by the governing performance model for the chosen configuration. Standard propagation effects and subjective weightings are used to radiate hemispheric noise levels to ground observers. The resulting computer program can be mathematically flown along prescribed trajectories to estimate ground noise radiation of several small UAV aircraft.
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