Robuta

https://saemobilus.sae.org/papers/a-ray-acoustics-approach-fuselage-scattering-rotor-noise-vfs-f47-2006 VFS-F47-2006: A RAY-ACOUSTICS APPROACH TO FUSELAGE SCATTERING OF ROTOR NOISE - Technical Paper ray acousticstechnical papervfsapproachfuselage