In flight control systems it is crucial to accommodate actuator failures for safe operation. Modern flight control systems are equipped with multiple power sources and actuation systems that offer redundancy in the event of actuator failures. Traditional approaches to flight control system design involve scheduling of fixed gain controllers and control allocation to take full advantage of redundant actuators. Alternative adaptive control approaches have been extensively investigated recently to provide enhanced fault tolerance by augmenting an existing flight control design with adaptive elements. This paper provides a brief background of the state of the art in adaptive fault tolerant flight control and presents a comparison study of several novel direct neural network based adaptive control methods. © 2008 by the American Institute of Aeronautics and Astronautics, Inc.