Noise reduction of UAS: Can acoustic materials provide a solution?

The growing deployment of Unmanned Aircraft Systems (UAS) introduces new challenges associated with their acoustic footprint. Excessive noise generated by UAS propulsion units is not only perceived as an undesirable disturbance but may also pose risks to human health and constrain the wider adoption of these technologies. This paper investigates the potential of acoustic materials and structural modifications as means of reducing UAS noise. The focus is placed on two approaches: the application of noise-reducing materials around the circumference of the propulsion unit, and the implementation of internal structures with varying infill ratios. A range of materials and configurations was tested to evaluate their impact on both noise levels and propulsion system thrust. The presented findings aim to provide insight into whether acoustic materials can serve as a viable approach to mitigating UAS noise while maintaining operational efficiency.