Design, Fabrication, and Testing of a Scaled Wind Tunnel Model for the Smart Wing Project

Building on the research performed during the DARPA/AFRL/NASA Smart Wing Phase 1 program (Kudva, J.N. et al. (July 1999). Overview of the DARPA/AFRL/NASA Smart Wing Program, SPIE Symposium on Smart Structures and Materials, Newport Beach, CA, Vol. 3674, pp. 230 6; Martin, C.A. et al. (1999). Smart Materials and Structures Smart Wing Phase 1 Final Report, AFRL-ML-WP-TR-1999-4162, Air Vehicles Directorate, Air Force Research Laboratory, Wright-Patterson Air Force Base, OH.) sought to improve vehicle aerodynamic efficiency using control surfaces actuated by smart materials, the goal of the Phase 2 effort was to develop larger scale, smart hingeless control surfaces capable of high-rate actuation and quantify their performance benefits at test conditions representative of operational flight environments. To achieve this goal, a 30-percent geometric scale, full-span wind tunnel model of a proposed Northrop Grumman Corporation (NGC) Uninhabited Combat Air Vehicle (UCAV) was designed and tested. The model incorporated conventional, hinged control surfaces on the left side and smart, hingeless control surfaces on the right to allow incremental aerodynamic performance comparisons; including lift increment due to unit control surface deflection (CL), and roll moment due to unit control surface deflection (Cld). This paper describes the design, fabrication, system integration, and ground test results of the Smart Wing Phase 2 model. Topics that are covered include: (1) wind tunnel model selection; (2) analysis and design procedure; (3) smart control surface integration; (4) model instrumentation; and (5) static load and Ground Vibration Test (GVT) results and correlation.