Knowledge Bank

Aerial reconnaissance plays a key role in gathering intelligence for the military. Unmanned aerial vehicles (UAVs) have proven that they can fulfill this role in a cost-effective manner. Furthermore, high-altitude UAVs fill this need well because they do not interfere with commercial air traffic. However, the effectiveness of these UAVs is subject to their range, endurance, and ease of deployment. High-altitude UAVs have an enhanced challenge of weight savings because there is less lift available at higher altitudes as air is less dense. Efforts to save weight for this class of UAV have proven catastrophic because they are designed for high-altitude flight and are susceptible to damage in turbulent areas of the lower atmosphere. To avoid this, it has been proposed to develop a tube-launched UAV deployed at the intended mission altitude. The wings of this UAV must be lightweight and easily folded and stowed in a tube. The wing must also be aerodynamically efficient to be a viable option for long-range aerial surveillance missions. Highly flexible polyimide wings fit these criteria; however, they have been experimentally shown to suffer losses in aerodynamic efficiency as a result of their flexibility. It has been shown in previous experiments that adding structure to the wing can increase aerodynamic efficiency. This research aims to determine ideal structure configuration to maximize the aerodynamic efficiency of such wings. This research will use wind tunnel testing to validate pressure distribution results obtained by Computational Fluid Dynamics. These pressures will then be translated to structural Finite Element models of wing concepts to determine an ideal configuration that maximizes aerodynamic efficiency while retaining low structural weight. Results are currently on-going, with the end goal being a drastic reduction in the cost associated with operating the high-altitude UAV.