An isolated full-scale XV-15 rotor was tested in helicopter mode in the NASA Ames 80 by 120-Foot Wind Tunnel. Extensive acoustic data were obtained to define the rotor operating condition for maximum blade-vortex interaction (BVI) noise. Additional data were obtained at operating conditions simulating flight up to 80 knots. An XV-15 aircraft was also tested under operating conditions corresponding to landing approaches for which BVI is expected to be a maximum. In-flight acoustic data were obtained using the YO-3A acoustic research aircraft. An attempt was made to closely match wind tunnel and flight test operating conditions. Details of the two tests are described and some representative acoustic results are presented. Comparisons are shown between the wind tunnel data and corresponding flight test data. Preliminary results indicate very good correlation of the BVI-related features. However, some differences between flight test and wind tunnel results exist away from the BVI event, thought to arise from differences in the two flow environments.
Comparison of Full-Scale XV-15 Wind Tunnel and In-Flight Blade-Vortex Interaction Noise
53rd American Helicopter Society Annual Forum ; 1997 ; Virginia Beach, VA, United States
1997-01-01
Conference paper
No indication
English
Comparison of XV-15 Full-Scale Wind Tunnel and In-Flight Blade-Vortex Interaction Noise
British Library Conference Proceedings | 1997
|British Library Conference Proceedings | 1993
|Blade Vortex Interaction Noise: A Comparison of In-Flight, Full-Scale, and Small-Scale Measurements
British Library Conference Proceedings | 1994
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