Noise reduction of the aircraft engine has been of importance since the beginning of jet liners. Acoustic characteristics of the installed engine as well as those of the engine itself would be useful for better noise assessment. Japan Aerospace Exploration Agency (JAXA) has conducted the noise tests using a business jet plane. The flight test includes the conventional acoustic measurement by microphones on the ground and the acoustic source localization using a microphone array. In parallel, the static test has been conducted using a turbo-fan engine installed on the plane. This paper describes the experimental results of the static test. The first part of the tests is the acoustic measurement by the far-field measurement and the source localization. The second part is the flow measurement on the pressure and temperature behind the engine. The far-field measurement made it clear that the fuselage and wing prevents the higher frequency tones from propagating whereas the jet mixing noise in the middle frequency is hardly affected by the shielding effect. The results of the flow measurement provided the properties necessary for the jet noise estimation using an empirical noise model.
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