In-flight Sound Measurements: A First Overview

A series of flight tests were carried out in June 2011 with more than 250 sensors in a cabin cross section upstream of the wings. The main purpose of the flight test was to qualify and quantify the main sources of cabin noise as well as the transfer paths to the passenger under real flight condition. The sensor set consists of pressure transducers installed in three dummy windows, accelerometers on the fuselage and the cabin and microphones inside the cabin. While varying the flight conditions by changing flight altitude, thrust and speed the main noise sources were distinguished and qualified.