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Charles D Smith

Publications and source records attributed to Charles D Smith.

3 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS2019

Noise Abatement Flight Test Data Report

An acoustic flight test of six helicopters conducted by NASA, FAA, and the US Army is described. Microphone arrays were used to collect acoustic data for source noise characterization, to investigate the acoustic impacts of maneuvering flight, and to develop and evaluate noise abatement operations for helicopters on approach. Atmospheric data and vehicle state data were also collected. Noise metrics are calculated and plotted for all conditions tested. All data described are publicly available upon request.

Rotorcraft↗
NASA NTRSDate not supplied

Medium-Sized Helicopter Noise Abatement Flight Test

An extensive flight test campaign was recently completed which aims to reduce the noise generated by helicopters in an effort to improve community acceptance. Using a ground-based microphone array, acoustic measurements were acquired on helicopters in the medium-size vehicle weight class over a number of flight conditions including steady level flight, steady descents, and approaches. While data were collected across four helicopters, the Leonardo AW139 and Sikorsky S-76D will be the focus of this paper. The extent of measured ground noise con- tours was limited due to the site constraints. Thus, the Noise Informed Community Environment Operations Planning System (NICEOPS) in conjunction with the flight test data was used to estimate how changes in the operating procedures impact noise exposure over a wider area during approaches. It was found that even small longitudinal accelerations can have a substantial influence on the noise generation processes during approach and must be modeled appropriately to develop new flight procedures which minimize the acoustic impact on the ground.

Flight Testing↗