Full-Scale Testing of Active Flow Control Applied to a Vertical Tail

Abstract

Full-scale wind tunnel tests were carried out on a Boeing 757 vertical tail equipped with 37 sweeping jet actuators on the starboard side along the rudder hinge line. The tests were performed at the National Full-Scale Aerodynamics Complex (NFAC) 40- by 80-Foot Wind Tunnel () at NASA Ames Research Center. The model was tested at a nominal airspeed of 100 knots across rudder deflections and sideslip angles that covered the airplane’s emergency single engine climb. Active flow control (AFC) was optimized at the maximum rudder deflection of 30° and sideslip angles of 0° and . A threshold success criterion of 20% increase in the maximum side force was exceeded at largest rudder deflection using 12 sweeping jet actuators in the absence of sideslip but barely reached it with 18 actuators at the maximum sideslip at a momentum coefficient input of approximately 0.5%; consequently, 31 actuators were selected for most tests. AFC caused significant increases in suction pressure and associated side force on the actuated side. The successful demonstration of this application cleared the way for a subsequent flight demonstration on the Boeing 757 ecoDemonstrator in 2015.