Wind Tunnel Testing for the SB>1 Defiant Joint Multi-Role Technology Demonstrator

Wind tunnel tests have been conducted to support development of the SB>1 DEFIANT™ Joint Multi-Role Technology Demonstrator. The objective is to provide data to validate and enhance the aerodynamic performance and flight dynamics models and to improve understanding of the aerodynamics of X2 TECHNOLOGY™ configurations. The first model was a 1/11 scale airframe with a powered propeller that was tested in the United Technologies Research Center (UTRC) Pilot Wind Tunnel (PWT) in 2013-2014. The second model was a 1/5 scale airframe with a powered coaxial main rotor that was tested at the U.S. Air Force National Full Scale Aerodynamic Complex (NFAC) in 2016. This model could also be tested with a powered propeller. Measurements included forces and moments on the various components, as well as fuselage, empennage, and blade surface pressures. For the 1/11 model, fuselage-induced flow fields at the propeller and empennage locations were also measured. Application of the experimental results to the State Space GenHel flight dynamics model is described.