This work is showing a new and promising way to reduce the void content in composite structures. The application of vibrating vents is creating a pulsing fluid pressure during the resin injection phase of the resin transfer moulding process. This is mobilizing trapped air bubbles in the preform. To prove the reduction of the void content a design of experiments study was carried out. Density measurements at different distances to the injection gate, which are directly related to the void content, are proving the beneficial aspect of this procedure. Furthermore, a statistical analysis was carried out revealing a significant reduction of the void content in zones far from the injection gate.