Improving Weapons Bay Acoustical Environments

The F/A-22 main weapons bay experiences severe acoustic loading when exposed to the freestream. The severity and attenuation of this loading is exacerbated by the flight envelope of the F/A-22 aircraft, as well as the requirement to carry and release “smart” weapons throughout this envelope. This extremely harsh environment can also impact components that are mounted within the bay itself, including carriage stores that contain sensitive electronics and control surfaces. CRAFT Tech proposes the development and demonstration of a robust flow control strategy that effectively lowers the tonal and broadband dynamic loading of the F/A-22 main weapons bay, while minimizing additional aircraft weight. This strategy (referred to as the “Hybrid Acoustic Suppression”) will employ flow control techniques applied to both the forward and aft portions of the bay, producing attenuation over the entire flight envelope and as the cavity characteristics switch between tonal and broadband. Phase I will involve technology maturation through high-resolution Large Eddy Simulation (LES), complemented by comprehensive wind tunnel testing with PIV flow visualization. The existing F/A-22 leading edge spoiler and aft wall ramp will serve as benchmarks from which acoustic benefit can be traded against any weight, cost, and/or aircraft/mission penalties.