Prediction of shaped sonic boom focusing.

Abstract

The focusing effects of aircraft maneuvers and accelerations on shaped, or minimized, sonic boom signals have been investigated. The spectrally accurate boom prediction methodology of Pilon [AIAA J. 45, 2149–2156 (2007)] has been enhanced to include the effects of focusing through an implementation of the nonlinear Tricomi equation solver of Auger and Coulouvrat [AIAA J. 40, 1726–1734 (2002)]. The newly enhanced prediction tool was used to predict boom focus from aircraft accelerations, turns, and dives. Idealized near-field shaped boom signals were used as inputs to the code. Both fully resolved, continuous boom signals and booms containing zero-thickness shock waves were used as inputs to the focusing algorithm, in order to highlight the differences in perceived loudness on the ground. The new tool and results of the study will be used to help design accelerations and maneuvers for future supersonic cruise aircraft.