POA * ONLINE SUBSCRIPTION ONLY

This Item provides a computerized method for estimating airframe noise in one-third octave bands over a frequency range set by the user. The OASPL is also computed. The polar and azimuthal angular ranges are specified by the user. Estimations are for free-field conditions in a still lossless atmosphere.

The method is a semi-empirical one and requires knowledge of the geometric data of the aeroplane and of ambient atmospheric conditions for its input. Airframe elements considered are the wing, the horizontal and vertical tailplanes, slats and flaps, and the undercarriage, any combination of which may be used in the calculation of airframe noise.

Computer programs, known as ESDUpac A9023, ESDUpac B9023 and VIEWpac M9023, are provided with this Item.