Three phases of XV-15 acoustic flight tests have been conducted over a five-year period by a NASA/Army/Bell Helicopter team to evaluate the noise reduction potential for tilt-rotor aircraft during terminal area operations. Lower hemispherical noise characteristics for a wide range of steady-state terminal area type operating conditions were measured during the phase 1 test and indicated that the take-off and level flight conditions were not significant contributors to the total noise of tilt-rotor operations. Phase 1 results were used to design low noise approach profiles being tested during the phase 2 and phase 3 tests, which used large area microphone arrays to directly measure the ground noise footprints. Approach profile designs emphasised noise reduction while attempting to maintain handling qualities sufficient for tilt-rotor commercial passenger ride comfort and flight safety under IFR (instrument flight rules) conditions. This paper discusses the weather, aircraft, tracking, guidance, and acoustic instrumentation systems, as well as the approach profile design philosophy, and the overall test program philosophy. Acoustic results are presented documenting the variation in tilt-rotor noise due to changes in operating conditions, indicating the potential for significant noise reduction using the unique tilt-rotor capability of nacelle tilting.
NASA/Army/Bell XV-15 tiltrotor low noise terminal area operations flight research program
NASA/Army/Bell XV-15 Schwenkrotor-Flugforschungsprogramm für lärmarmen Betrieb im Flughafenbereich
Journal of the American Helicopter Society ; 47 , 4 ; 219-232
2002
14 Seiten, 17 Bilder, 1 Tabelle, 21 Quellen
Article (Journal)
English
Bahnverfolgung , Drehflügelflugzeug , Flugeigenschaft , Flughafen , Fluglärm , Flugregelung , Forschungsprogramm , Führungssystem , Instrumentenlandeverfahren , Lärmminderung , Lautstärkemessung , Luftfahrzeug , Rotor (Drehflügel) , Schallemissionsprüfung , stationäre Eigenschaft , Untersuchungsergebnis , Versuchsaufbau
NASA-Army-Bell XV-15 Tiltrotor Low Noise Terminal Area Operations Flight Research Program
Online Contents | 2002
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