Analysis of VTOL Downwash and Outwash to Establish Vertiport Safety Standards: A Theoretical Approach
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Abstract
VTOL aircraft are expected to play a crucial role in the air transportation sector, fulfilling various use cases similar to helicopters. However, they also present a significant safety hazard, downwash, which is the concentrated and powerful airflows generated by the rotors or propellers. To mitigate downwash risks, clear communication, proper training, and the establishment of safe operating zones are essential. The study suggests that existing FAA vertiport design criteria are insufficient as they lack minimum standards for downwash and outwash safety. This study identified the dangers of VTOL downwash and developed potential mitigation strategies and basic safety guidelines. The study used existing VTOL aircraft data to calculate theoretical airflow characteristics and then compared these to wind speed comfort and safety scales. Equations based on design dimension “D” as described in existing vertiport literature were provided. In addition, equations accounting for variations in VTOL design and propulsion configurations were developed. A resultant process for determining safety zones and buffer areas around vertiports is provided. The findings of this study can assist advanced air mobility stakeholders in the development of vertiport safety guidelines and protections.
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