An Unmanned Aerial Vehicle, UAV for short, is able to fly autonomously during all phases of flight, but has to be monitored from an operator station. In this article a better avionic system is proposed to optimize this process reducing the channel usage without quality degradation. The information related to the aircraft position is called telemetry. This early avionic system is tested in the longitudinal mode of a high wing model unmanned aircraft system in an open source flight simulator.