Aerodynamic analysis was performed on a hybrid VTOL/fixed wing UAV from Yonah in forward flight mode. The aircraft was characterized for the first time, leading to more accurate performance estimates and identification of areas for improvement.
We performed a drag breakdown and assessed that the rear landing gear and booms are performing poorly. In particular, the large separation zone behind the rear landing gear contributes to high pressure drag. The relatively flat planar front surfaces of the boom also leads to high pressure drag.
A reduction in the frontal area of the rear landing gear, as well as streamlining of the motor mounts were suggested. The CFD results allow us to quantify the potential increase in the lift to drag ratio (and hence approximately range) by 15%. More details are shared in this post.