Abstract: There are many problems in current detection methods such as conditional limitations and complexity of calculation which make them not easy to be put into practical application. The relationship between the servo motor information and the failure of the control surface was analyzed, and a method of detecting the failure rate of the control surface by using the servo current information in combination with the aerodynamic model was proposed. The result of its hardware-in-the-loop simulation shows that the detection system can quickly and accurately output the failure rate within 1 second which is a conservative estimate. That makes the reconfiguration system have a greater chance to regain the effective control of UCAV and increase the survivability of UCAVs that are damaged in the fights.

Key words: control surface failure, fault diagnosis, aircraft modeling, HILS