A General Prediction Procedure for Light Propeller Driven Aeroplane Flyover Noise Signatures

Abstract

Noise emission characteristics of propeller-driven aeroplanes (i.e. General Aviation aircraft) are the essential input data for immission calculations to be performed for airfields in Germany. In contrast to presently available calculation procedures, in this paper such characteristics shall be based on modern propeller noise calculation schemes rather than employing empirically determined "aircraft noise-categories". Propeller noise predictions were performed utilizing a time-domain calculation scheme, however, related to a "representative constant" blade geometry, a fixed radial blade loading distribution and typical blade lift- and drag coefficients. As a consequence of such simplifications calculated noise data need to be checked against measured noise levels. Once the simplified noise prediction code has thus been "calibrated" it could be used directly to calculate noise levels as a function of overall design- and operational parameters.