Cornerstone Research Group, Inc. (CRG), proposes to demonstrate feasibility in the reduction of noise attributed to drainage slots in jet engine acoustic liners. This will be accomplished through the development of design rules for optimum slot design and the implementation of adaptive material technologies. CRG proposes to bring this technology to a technology readiness level (TRL) 2 after the Phase 1 effort and a TRL 4 after the Phase 2 effort. The proposed innovation lies in the recognition that drainage slots in the honeycomb of an acoustic liner may have a significantly adverse effect on its ability to absorb noise. This limits the ability of the acoustic liner to achieve its full potential. The proposed research will enable the acoustic designer to understand and to accurately model the effects of drainage slots on the acoustic impedance characteristics. It will also provide the impetus to find solutions that will counteract the adverse effects of drainage slots through adaptive means.