AFRL Takes Aim at Turret Efficiency, Performance Published June 20, 2012 By Holly Jordan Air Vehicles WRIGHT-PATTERSON AIR FORCE BASE, Ohio -- Air Force Research Laboratory researchers completed wind tunnel tests designed to investigate the performance of feedback flow control devices around aircraft turrets. One goal of this research is to improve the performance of high-energy lasers aboard aircraft. During the Feedback Flow Control Turret Test, conducted at the AFRL Subsonic Aerodynamic Research Laboratory (SARL), researchers tested a turret equipped with 20 suction slots placed around the turret aperture. These devices are used to manipulate the airflow to help reattach the flow as the vehicle is in motion. Sensors placed around the turret allowed researchers to measure flow and develop algorithms to maximize the efficiency of the devices. Achieving reattached airflow over a turret is important for several reasons: separated airflow can cause distortion in a beam emanating from the turret; attached airflow lessens the distortion. Therefore, transmission of the beam to target is much more accurate. As a side benefit, reattached airflow reduces drag over the turret, improving the aerodynamic efficiency. The tests were conducted at wind tunnel speeds of Mach 0.3, using diagnostic techniques including Particle Image Velocimetry to measure flow velocity, and a Malley Probe to measure aero-optic distortion. All tests were completed successfully, with researchers gaining data to further the understanding of these types of flow control devices. In addition to turrets, AFRL is studying different applications for which feedback flow control can prove beneficial. All fighters and bomber aircraft could benefit from the energy-saving aspects of this technology.