Noise Transmission Studies of an Advanced Grid-Stiffened Composite Fairing

Steven A. Lane, Scott Kennedy, Robert Richard
2007 Journal of Spacecraft and Rockets  
Interior fairing noise is an important consideration for payload launch survivability and has been studied extensively since the beginning of the space program. This work presents acoustic transmission studies conducted by the Air Force Research Laboratory, Space Vehicles Directorate, on a composite, grid-stiffened, Minotaur payload fairing. These tests were performed in an acoustics laboratory and examined the effects of acoustic flanking paths, the thermal protection system, and melamine-type
more » ... , and melamine-type acoustic blanket treatments on fairing noise. The data showed that acoustic flanking paths significantly increase noise transmission, especially at low frequency. The bare fairing with thermal protection system provided approximately 14 dB of noise reduction over the 5000 Hz bandwidth relative to external levels. Acoustic blanket performance was measured as a function of bandwidth, surface area coverage, and mass. It was observed that small amounts of treatment (2 kg) significantly increased noise reduction (3.6 dB), even at low frequency.
doi:10.2514/1.28590 fatcat:ipsm2rqovvgsxiey4txtkkcz4y