Impact of Operational Reliability Re-assessment during Aircraft Missions

International audienceDependability assessment, by system manufacturer, during aircraft design, based on stochastic modeling, is common practice, but model based operational dependability assessment in the way described in this paper and in real-time is seldom done. Usually, the stochastic assessment addresses aircraft or mission safety, and does not specifically tackle aircraft maintenance during its operation. This paper will address an aircraft mission operational reliability as resulting from component failures, environment changes, and maintenance facilities offered at the various stops involved in the mission. We will show how the on-line assessment of operational reliability will help adjust an aircraft mission, in case of major changes during the mission. The assessment is made possible thanks to the building and validation of a generic dependability model that is easily i) processed for the assignment of an initial mission, and ii) updated during mission accomplishment, following the occurrence of some specific major events. The generic model can be built as early as the design phase, by engineers who are specialist in dependability assessment, based on stochastic processes. Model update and processing, during aircraft operation, can be achieved by operators who are not necessarily familiar with stochastic processes in the way that they are being applied in this research. We will present examples of results that show the valuable role of operational dependability re-assessment during aircraft missio

Fiabilité opérationnelle des avoins (Approche basée sur les modèles et cas d'étude)

Lors de la conception des avions, il est courant que les constructeurs évaluent la sûreté de fonctionnement en utilisant des modèles stochastiques, mais l'évaluation de la fiabilité opérationnelle à l aide de modèles en ligne, pendant la réalisation des missions, reste rarement effectuée. Souvent, l'évaluation stochastique concerne la sécurité des avions. Cette thèse porte sur la modélisation de la fiabilité opérationnelle des avions, pour aider à la planification des activités de maintenance et des missions, ainsi qu à la bonne réalisation de ces dernières. Nous avons développé une approche de modélisation, basée sur un méta-modèle qui sert de base i) de structuration des informations nécessaires à l évaluation de la fiabilité opérationnelle d un avion et ii) pour la construction de modèles stochastiques pouvant être mis à jour dynamiquement. La mise à jour concerne l'état courant des systèmes avion, un profil de mission et les moyens de maintenance disponibles dans les diverses escales incluses dans le profil de la mission. L'objectif est de permettre l'évaluation de la fiabilité opérationnelle en ligne. Deux cas d études, basés sur des sous-systèmes avion, sont considérés à titre d'illustration. Nous présentons des exemples de résultats qui montrent le rôle important de l évaluation de la fiabilité opérationnelle pendant une mission d avionDependability assessment, by system manufacturer, during aircraft design, based on stochastic modeling, is of common practice, but model based operational dependability assessment online, during missions' achievement, is seldom done. Usually, the stochastic assessment addresses aircraft safety.This thesis addresses aircraft operational dependability modeling to support mission and maintenance planning, as well as the achievement of the missions. We develop a modeling approach, based on a meta-model that is used as a basis i) to structure the information needed to assess aircraft operational reliability and ii) to build a stochastic model that can be updated dynamically. The update concerns the current state of the aircraft system, a mission profile and the maintenance facilities available at the flight stop locations involved in the mission. The aim is to enable operational reliability assessment online. Two case studies, based on aircraft subsystems, are considered for illustration. We present examples of evaluation results that show the valuable role of operational dependability assessment during aircraft missionTOULOUSE-INSA-Bib. electronique (315559905) / SudocSudocFranceF