Why does the Falcon-9 booster make a triple sonic boom during flyback? An initial analysis
Year: 2025
Type: article
Abstract: When the SpaceX Falcon-9 rocket booster descends through the atmosphere after a launch, it produces a sonic boom with three shocks in the far field, rather than the usual two-shock N-wave. In this Letter, the additional shock's origin is explained using sonic boom theory, nonlinear propagation modeling, computational fluid dynamics, and photographic evidence. The extra central shock results from a forward-migrating compression wave caused by the grid fins merging with a rearward-migrating rarefaction wave caused by the lower portions of the booster, including the folded landing legs.
Source: JASA Express Letters
DOI: 10.1121/10.0035649
Authors: Mark C. Anderson, Kent L. Gee
Institution: Brigham Young University
Language: English
Subfield: Aerospace Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: diamond
OpenAlex ID: W4407406316