A system for controlling aircraft boundary layer airflow comprising a frame structure configured to be coupled or integral to an inner surface of an aircraft nacelle, the frame configured to support to the nacelle, and/or a modular plenum configured to be received by the frame structure, the modular plenum comprising a truncated tetrahedron intersected at its apex by a duct. The frame may comprise a plurality of sub-frames. The system may further comprise a plurality of modular plenums, each configured to fit within a sub-frame. The system may further comprise a flexible material configured to couple a first duct to a second duct. The system may further comprise a nacelle configured to receive the system.