Enhanced detection and isolation of angle of attack sensor faults

An enhanced detection and isolation method to monitor the state-of-practice triplex redundant angle of attack measurements on modern civil transport aircraft is presented. The developed fault detection and diagnosis architecture relies on advanced model and signal based techniques monitoring each of the three sensors individually. This allows the correct isolation of erroneous sensors also in case of multiple sensor faults. The gathered isolation information is used in an advanced sensor fusion scheme, allowing the propagation of an adequate angle of attack value to the flight control computer in case of failure. The fault detection and diagnosis system is validated using a high fidelity benchmark model of a large commercial transport aircraft using different wind excitations together with challenging pilot and auto-pilot scenarios.