ASA 129th Meeting - Washington, DC - 1995 May 30 .. Jun 06
1pPA9. Sonic-boom noise penetration into the ocean: 1995 update.
Victor W. Sparrow
Grad. Prog. Acoust., Penn State Univ., 157 Hammond Bldg., University Park,
PA 16802
This talk is an update to a previously given presentation [
1850--1851 (A) (1993)] in which a first-pass model for the penetration of sonic
boom noise into the ocean was described. Since that presentation was given, a
number of refinements to the theory have been identified, the primary of which
is the effect of aircraft Mach number on the duration of the sonic boom. The
general trend for aircraft flying at a fixed altitude is that the evanescent
acoustic wave underwater due to a sonic boom penetrates more deeply for
increased aircraft speeds [ 159--162 (1995)]. Other refinements
currently under development include appropriate initial models for sound level
decay as a function of depth and for focusing and defocusing of the penetrating
sonic boom noise by ``frozen'' sinusoidal and trochoidal ocean surface waves.
[Work supported by NASA Research Grant NAG-1-1638.]