A ventilating and particle-filtering airflow system, and related methodology, for managing the flow of air to the brush region of an on-board aircraft (vehicle) electrical generator. Conduit structure collects intaken air during aircraft (vehicle) engine operation, filters this air to capture and prevent the passage of particles, and directs filtered airflow to that brush region. Water drainage is provided for in a region near where filtering takes place. The filtered airflow is substantially the only airflow admitted to this region.