Safety in aircraft systems is a concern of rising importance, especially due to the sophisticated control devices exploited to improve the overall system performance, including both digital designs and complex hardware (input-output sensors, actuators, and components). Thus, control systems must include automatic supervision tasks to diagnose incipient malfunctions, as early as possible. This book focuses on the design of robust linear and nonlinear dynamic filters, obtained via model-based and analytical approaches for fault diagnosis and identification. The problem is treated in all its aspects covering: nonlinear modelling of aircraft systems; design of disturbance decoupled dynamic filters for residual generation; fault detection and estimation, fault tolerant control. Sample case studies are used to demonstrate the application of these techniques to high fidelity flight simulators. This book will be of interest to researchers in aircraft fault tolerant control, fault detection and diagnosis. Aircraft control engineers interested in applying the latest methods in fault detection and diagnosis will benefit from the simulation examples.