Flyover Noise Computations of the Joby Aviation Aircraft

Abstract

Joby Aviation is developing a six propeller, all electric vertical takeoff and landing aircraft. The aircraft is designed to operate near high population areas such as residences and workplaces, so it is imperative that the acoustic emissions of the aircraft are minimized for community acceptance. The aircraft design process incorporated the usage of high-fidelity computational aeroacoustics methods. Acoustic flight tests of the Joby aircraft were conducted by the National Aeronautics and Space Administration as part of the Advanced Air Mobility National Campaign and confirmed the revolutionary low noise footprint. The measured noise levels were compared with high-fidelity computational aeroacoustics predictions for two steady, level flight conditions. The results provide insight into the noise sources of the aircraft in these flight conditions. Airframe noise was predicted to be dominant for both flight conditions in the A-weighted spectrum due to the low propeller loading. Modeling efforts were made to account for acoustic shielding and airframe broadband noise and resulted in an improvement in the predictions, although the true noise sources are to be confirmed with further investigation.