Annotation: In this paper, three robust control methods for the uncertain dynamic model of Skywalker X8 flying-wing unmanned air vehicle are designed: mu-synthesis, robust proportional integral derivative control and adaptive robust proportional integral derivative control using optimization. The implementation feasibility of designed robust control systems based on the capabilities of the autopilot hardware is investigated. A robust proportional integral derivative and robust adaptive proportional integral derivative control are designed based on the considerations of the robustness of the system's behavior as well as hardware considerations. With a robust control system based on mu-synthesis, it is possible to achieve better reference signal tracking and disturbance rejection. But the hardware processor speed of the existing autopilot makes it impossible to implement this controller. Two parallel microcontrollers or a dual-core microcontroller must be used to implement a control system based on the musynthesis. Designed robust adaptive proportional integral derivative controller for roll channel was implemented in the existing autopilot and tested in flight test. Flight test results with adaptive robust proportional integral derivative controller show better disturbance rejection in the roll channel than the traditional one.