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Critical control systems are often built as a combination of a control core with safety mechanisms allowing to recover from failures. For example a PID controller used with triplicated inputs. Typically those systems would be designed at the model level in a synchronous language like Lustre or Simulink, and their code automatically generated from those models. In previous SAE symposium, we addressed the formal analysis of such systems - focusing on the safety parts - using a combination of formal techniques, ie. k-induction and abstract interpretation. The approach developed here extends the analysis of the system to the control core. We present a new analysis framework combining the analysis of open-loop stable controller with those safety constructs. We introduce the basic analysis approaches: abstract interpretation synthesizing quadratic invariants and backward analysis based on quantifier elimination.

The seventh European Framework Program (FP7) “Personal Plane” project (PPlane) aims at developing system ideas to enable personal air transport in the long term (2030 and beyond). Such a system will avoid the ever increasing congestion on European roads and offer an alternative to the current conventional transport system across Europe, in particular in those states that still have poor highway and railway networks. The preliminary assumption made in the PPlane project is that automatisms should be developed to enable a “regular Joe” to use a personal aircraft, in various weather conditions, without any command and control difficulties, using a “push button” navigation interface. An on-board automatic system will take care of the complex issues of integration into the airspace (other sky users, class of airspace, Special Use Airspace…), navigation and emergency management.

Avionics systems distributed on AFDX networks are subject to stringent real-time constraints that require the system designer to have techniques and tools to guarantee the worst case traversal time of the network (WCTT) and thus ensure a correct global real-time behavior of the distributed applications/functions. The network calculus is an active research area based on the (min,+) algebra, that has been developed to compute such guaranteed bounds. There already exists several academics implementations but no up to date industrial implementation. To address this need, the PEGASE project gathers academics and industrial partners to provide a high quality, efficient and safe tool for the design of avionic networks using worst case performance guarantees. The PEGASE software is an up-to-date software in the sense that it integrates the latest results of the theories, in tight cooperation with academics researchers.

Within the European Integrated Project NACRE (New Aircraft Concept REsearch) led by Airbus, a team of research centers and universities developed a multidisciplinary flying testbed called IEP (Innovative Evaluation Platform). Under the form of a dynamically scaled model of a future civil transport aircraft, its role is to assist engineers during the assessment of flight dynamics characteristics and noise reduction capabilities. After the feasibility study during which potential scientific and economical benefits of such new test facility have been identified, the team decided to design and manufacture the IEP. Because of the dual aspect of the system (it is a flying unmanned aerial vehicle and a test facility), an extensive requirement analysis has been carried out by the partners in order to identify the necessary operational modes and their associated navigation and control strategies.

This paper describes the microaccelerometer ASTRE, developed as Laboratory Support Equipment of Columbus, to monitor the residual microgravity disturbance level in the very low frequency range. ASTRE will be integrated in the already flown Microgravity Measurement Assembly (MMA). The paper recalls the microgravity environment which is required on-board Columbus and shortly describes expected discrepancies between the requirements and the predicted, more noisy, situation.

This paper presents a work carried out within the FULMEN lightning-on-aircraft oriented European project. It is the second part of the general presentation on the analysis of EM environment inside the aircraft. Therefore, it focuses on numerical calculations of voltage and current transfer functions on the ports of the same prototype wiring harness installed in several aircraft structures. The calculations have been carried out with the cable network CRIPTE code and rely on 3D field calculations performed by Ericsson Saab Avionics. The link between the cable code and the 3D code is achieved through the component of the incident electric field tangent to the running path of the wiring.

Icing is a major hazard for aviation safety. Over the last decades an additional risk has been identified when flying in clouds with high concentrations of ice-crystals where ice accretion may occur on warm parts of the engine core, resulting in engine incidents such as loss of engine thrust, strong vibrations, blade damage, or even the inability to restart engines. Performing physical engine tests in icing wind tunnels is extremely challenging, therefore, the need for numerical simulation tools able to accurately predict ICI (Ice Crystal Icing) is urgent and paramount for the aeronautics industry, especially regarding the development of new generation engines (UHBR = Ultra High Bypass Ratio, CROR = Counter rotating Open Rotor, ATP = Advanced Turboprop) for which analysis methods largely based on previous engines experience may be less and less applicable. The European research project MUSIC-haic has been conceived to fill this gap and has started in September 2018.

The aim of this work is to develop a semi-empirical model for erosion phenomena under ice crystal condition, which is one of the major phenomena for ice crystal accretion. Such a model would be able to calculate the erosion rate caused by impinging ice crystals on accreted ice layer. This model is based on Finnie [1] and Bitter [2] [3] solid/solid collision theory which assumes that metal erosion due to sand impingement is driven by two phenomena: cutting wear and deformation wear. These two phenomena are strongly dependent on the particle density, velocity and shape, as well as on the surface physical properties such as Young modulus, Poisson ratio, surface yield strength and hardness. Moreover, cutting wear is mostly driven by tangential velocity and is more effective for ductile eroded body, whereas deformation wear is driven by normal velocity and is more effective for brittle eroded body.