We present Flying Frustum, a 3D spatial interface that enables control of semi-autonomous UAV (Unmanned Aerial Vehicles) using pen interaction on a physical model of the terrain, and that spatially situates the information streaming from the UAVs onto the physical model. Our interface is based on a 3D printout of the terrain, which allows the operator to enter goals and paths to the UAV by drawing them directly on the physical model. In turn, the UAV’s streaming reconnaissance information is superimposed on the 3D printout as a view frustum, which is situated on the physical model according to the UAV’s location on the actual terrain. We argue that Flying Frustum’s 3D spatially situated interaction can help improve human- UAV awareness, allow a better operators-to-UAV ratio, and enhance the overall situational awareness. In this video we illustrate the design and demonstrate the proof-of-concept system of Flying Frustum.