Detection and elimination of underground obstacles is a topic of active research. Multipurpose of applications range from geological, agricultural, ecological and forestry growth monitoring to military related applications like mine detections. Variety of detection methods are used and reported in the literature, e.g. a broadband ground penetrating radar is essential for detection of buried objects [1]. The detection is not only limited to metallic objects but to plastic designs like some sorts of mines [2]. For the latter ones, it was demonstrated that that a thermal camera could successfully detect such objects from an elevation of 10 meters. All those devices are mounted on and carried by low-altitude flying UAVs, which collect data onboard and evaluate afterwards or in the real time. The main purpose of our study is to design a feedback system consisting of three quadcopter type UAVs and the moving vehicle to avoid underground obstacles. The UAVs need to cover and monitor the field in front of vehicle in the real time. The contribution and the novelty of our approach is to make the feedback effective in the sense of combining the UAV battery consumption, the tight field area coverage, real-time communication with the vehicle, and possibly low cost of the whole UAV equipment. The proposed feedback loop is illustrated by the simulation scenarios. They enable us to effectively compare, for the first approach, the field coverage by the UAVs trajectories, various sensor kinds and their scanning capabilities versus the battery energy consumption.