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In this article the H  fault detection and diagnosis technique is applied to a representative twin-engine civil commercial aircraft. The specific failure scenario contemplated concerns the detection of an abnormal aircraft behavior leading to the degradation of the aircraft performance. This abnormal configuration is caused by an actuator or a sensor failure in the control loop of a control surface, between the Flight Control Computer and the moving surface, including these two elements. The definition of the aircraft benchmark, model and fault problematic, and the development and application of the FDD technique application is part of a European Framework Programme project named Advanced Fault Diagnosis for Sustainable Flight Guidance and Control. The results, including nonlinear time domain simulations in the closed-loop functional engineering simulator, show the promising performance and robustness of the proposed solution.

Next generation space exploration missions will require extremely versatile vehicles that should be able to safely carry both cargo and crew to LEO and beyond LEO destinations and back to Earth. The re-entry phase is very important for the success of such missions and becomes critical in the case of high speed (high energy) entries, which arise in Lunar and Mars missions. Moreover, modern requirements call for flexibility for long ranges, and in case of a low L/D vehicle a controlled skip would be necessary to obtain such requirements. This article presents the development of a fully integrated guidance and control (G&C) system as part of a complete robust GNC system for high-speed entry. An Apollo derived guidance method and a QFT designed attitude control system have been implemented to guide a conical capsule in the context of a long range skip entry from a Lunar return mission. The system has been extensively tested, with 6 degrees-of-freedom simulations performed on re-entry scenarios developed using a high-fidelity functional engineering simulator. The vehicle is steered to the desired landing site and successfully controlled during the most critical phases of the trajectory, being pull out, exit of the atmosphere to perform the commanded skip, and the final entry with reduced velocity. The G&C scheme has proved robust against realistic modeling of dispersions and uncertainties throughout the re-entry.

In this article, an architecture addressing the interaction between the health monitoring and control modules for launcher's rocket engines is proposed. The first module is responsible for the monitoring tasks (diagnosis, prognosis and decision), while the second for the control tasks (management, reconfiguration and sequencing). For launchers, these two modules are typically designed and implemented in an independent manner since,most often times, the rockets' controllers follow a set of limited and clear instructions (e.g. change operating set-point or perform engine shut-down) not requiring detailed monitoring information. The new generation of launchers is envisioned to utilize advanced controllers and monitoring modules that will allow optimizing the performance of the mission while improving the dependability of the system. In order to carry these modules on-board it is necessary to examine their interaction from a functional and architectural point of view. Such an interacting architecture is proposed and exemplified in this article as part of the technological investigations performed within the European Space Agency Future Launcher Preparatory Programme (FLPP).

This article presents the motivation, goals and benchmark problems of a study from the European Space Agency entitled "Robust Flight Control System Design Verification and Validation Framework" (RFCS). The objective of the study is to develop, demonstrate and compare the potential of modern control design, analysis and modeling techniques to address complex issues currently not well covered in the traditional launchers' verification and validation (V&V) process. The identification of these V&V gaps have resulted in a set of benchmark problems that allow comparing the standard results with those arising from the application of the advanced techniques. The benchmark problems are extracted from the VEGA launcher and its V&V process, but their significance is more general as they represent common issues found in most launchers.