Sonic boom minimization revisited

Abstract

We revisit the classical Jones-Seebass-GeorgeDarden theory of sonic boom minimization, noting that minimum achievable sonic boom is related to the aircraft's weight divided by the three-halves power of its length. We then summarize studies of sonic boom acceptability and the effects of vibrational relaxation on very weak shock waves, This leads us to conclude that a small, appropriately designed, supersonic business jet's sonic boom may be nearly inaudible outdoors and hardly discernible indoors.

Multilevel optimization of a supersonic aircraft

“…Furthermore, a direct evaluation of the shock signature on the soil from the 3D Euler equations is nowadays computationally out of reach. It is necessary to model the far-ÿeld sonic boom propagation, an issue described both in [3] through the pioneering works of Witham about the matter, and in [4]. The central idea in Witham's theory is to propagate bi-dimensionally, in a vertical plane spanned by the ight direction, the near ÿeld shock wave pattern, assuming some (indeed strong) hypotheses.…”

“…According to [4], there are three optimization goals related to ground pressure signatures, shown in Fig. 3: the impulse, the ISPR and the ÿnite rise time.…”

“…Therefore, the reduction of the sonic boom is an important issue in the speciÿcation of the next generation of supersonic aircrafts [3,4]. According to [4], sonic boom minimization could be attained by considering basically three points: to get the minimum pressure impulse, which is deÿned as the integral of the absolute value of the overpressure ground signature, or the minimum initial shock pressure rise or ÿnally to smooth the pressure rise by distributing it in a longer rise time. Di erent optimization strategies focus on one or several of these possibilities.…”

Generation of Parametric Equivalent-Area Targets for Design of Low-Boom Supersonic Concepts

“…Seebass and Argrow [7] give a comprehensive review of the historical development of boom minimization theory and call it the classical Jones-Seebass-George-Darden theory. Existing theories for generating low-boom targets are based on parametric forms of the F-function [3]- [6], which can be converted to a low-boom target A e (see ref.…”

“…Moreover, numerical optimization can be used to generate the optimal A e target for given A e volume constraints. This approach is different from the existing target generation processes that use parametric F-functions [3]- [7]. The approach aims at eliminating the practical difficulties of using the design parameters of an F-function to obtain an A e target that satisfies the volume constraints of a low-boom concept.…”