Rotorcraft Noise Ground Footprints Estimation and Preliminary Lower Noise Flight procedure design Using DLR Flight Test Data

Abstract

DLR noise abatement flight procedure design code, HEMISPHERE is currently under development. The purposes of the development are to assess acoustic ground footprints over a large area, using acoustic data gathered from only limited ground microphones and to design lower noise flight procedure based on either flight test data or purely numerical simulations. The major elements and their functions in the HEMISPHERE code as well as the code validation using pure numerical simulation results were described in reference. This report gives a brief description of DLR flight test as well as a discussion on ground footprints estimation using flight test data. HEMISPHERE code validation and the noise ground footprints estimation using DLR aeroacoustic flight Test Data are presented, and finally a preliminary manually established noise abatement flight procedure is demonstrated.