飞翼布局飞机气动效率高, 常被太阳能飞机所采用, 但操稳特性较差. 平直翼飞翼布局飞机具有与主流后掠飞翼布局飞机不同的气动特性. 使用涡格法计算了轻小型平直翼飞翼布局无人机的气动力系数与气动导数, 分析了某验证机的俯仰静稳定性及不同迎角、爬升角下的纵向与横航向稳定性, 讨论了重心位置低于机翼平面对其稳定性的影响, 并制作航空模型试飞. 研究发现, 平直翼飞翼布局飞机的纵向稳定性与常规布局飞机不同, 可以在无增稳条件下维持横航向稳定, 荷兰滚倾向弱. 重心位置降低可以改变配平迎角, 使其在正迎角下俯仰更稳定, 但会使其在负迎角或大爬升角下的俯仰稳定性恶化. 飞机在飞行中表现出多种特殊行为, 需要进一步研究.

Flying-wing aircraft are known for their high aerodynamic efficiency and are often utilized in solar-powered aircraft. However, they generally exhibit poor stability and controllability. Unswept-wing flying-wing aircraft, also called “flying planks”, possess aerodynamic characteristics that differ from swept-wing flying-wing designs. This study utilizes the vortex lattice method to calculate the aerodynamic coefficients and derivatives of a lightweight, small-scale, unswept-wing flying-wing unmanned aerial vehicle (UAV). The study analyzes the longitudinal static stability, longitudinal and lateral-directional dynamic stability under varying angles of attack (AoAs) and climb angles as well as the effects of the centre of gravity (CG) position below the wing on the stability of the UAV.An aeromodel is constructed and test-flown to validate the findings. Results show that the longitudinal stability of the unswept-wing flying-wing aircraft differs from that of conventional configurations. These aircraft show almost no tendency for dutch-roll, and maintain lateral-directional stability without stability augmentation. Lowering the CG position can alter the trimmed AoAs, and enhance the pitch stability at positive AoAs and deteriorates the pitch stability at negative AoAs or large climbing angles; it also narrows the flight envelope. Unswept-wing flying wings possess various unconventional characteristics during flight and need further investigation.