Variable Swept-Angle Air Launched UAV Design and Characteristic Analysis

The air-launched unmanned aerial vehicles are transported and deployed by air platforms to execute reconnaissance, cluster penetration, and rapid strike missions against beyond-defense-zone targets. A large aspect ratio, variable swept folding and air launched UAV was present to realize the capabilities of long-endurance reconnaissance and high-speed attack. The design specifications are as follows: takeoff weight ≤ 5 kg, cruising speed of 100 km/h, and attack speed of 160 km/h. It features an inverted V-shaped aerodynamic layout and a slowly controllable variable-sweep wing structure driven by a worm gear. The detail parameters design was completed for both the wings and tail. Aerodynamic simulations and characteristic estimations were conducted with OpenVSP. The results indicate that, as the sweep angle increases from 0° to 45°, the lift coefficient, drag coefficient, and lift-to-drag ratio decrease, while the flight speed increases by 60%, which could significantly enhance terminal attack efficiency. However, the sweepback process is accompanied by a rearward shift of the center of pressure, which improves the static stability of the UAV but has an impact on its maneuvering control capability.