|MadSci Network: Physics|
The Shuttle hits Mach 1 while flying over the Atlantic Ocean; thus the shock wave impinges the Earth, causing a pressure differential, over the ocean's surface, and not on land near the viewing area. If a portion of the shock wave were to pass over the visitor's viewing area, it would be inaudible due to the noise level of the SRMs (Solid Rocket Motors). -Dennis
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