Acoustic Analysis of the Firefly Alpha Launch Anomaly

In September 2021, during Firefly Aerospace's inaugural launch of the Firefly Alpha, an unexpected anomaly occurred, resulting in the shutdown of one of the four boosters. With the thrust decreasing by a factor of 3/4th, we anticipate observing distinct changes in the peak spectral frequency and an overall reduction in sound pressure levels. This study examines the acoustic signatures associated with the anomaly. We specifically focus on the shift in peak spectral frequency and the attenuation of sound pressure levels. The insights derived from this analysis could offer a valuable opportunity to validate our current understanding of rocket sound source models, enhancing our comprehension of rocket noise.