Accession Number : AD0775095

Title :   A Numerical Study of the Effects of Aircraft Manoeuvers on the Focussing of Sonic Booms,


Personal Author(s) : Onyeonwu,Ronald O.

Report Date : JUL 1973

Pagination or Media Count : 119

Abstract : The effects of aircraft maneuvers on the focusing of sonic booms are investigated for a model atmosphere which is piecewise linear in wind and sound speeds, and piecewise constant in wind direction. Ray-tube areas and trajectories are obtained in closed form for a real atmosphere with winds and aircraft in arbitrary maneuvers. A mathematical formalism is developed for identifying the focusing ray in general maneuvers, leading to a direct and accurate determination of the caustic surface ground intercept. The algorithms derived in the analysis complement those of Hayes to form the basis for a computer program for predicting sonic boom properties. There appears to be a ten-fold reduction in computing time as compared with the Hayes-Haefeli program. (Modified author abstract)

Descriptors :   *Jet aircraft, *Flight maneuvers, *Sonic boom, *Focusing, Shock waves, Acoustic beams, Ray tracing, Atmosphere models, Mathematical models, Canada

Subject Categories : Aircraft

Distribution Statement : APPROVED FOR PUBLIC RELEASE