Launch System Hazard Study: Methodology and Lessons Learnt after 5 years of Application

Abstract

ABSTRACT Risk management for new launch vehicles issuing from different origins and original industrial organizations, was a great challenge. In order to assess risk for launch operations, a specific type of risk analysis from take-off along the flight is performed. This analysis is called Launch System Hazard Study. The method is a classical one for high-risk industry, for which all the risks shall be assessed and mastered. These classical studies identify the hazard on ground and establish the risk mitigation to reduce the risk occurrence (prevention measures) and/or to minimize the effect (correction measures), like in particular the evacuation of the hazard zone. One of the main differences between the risk industry and the launch vehicle is that the latter is a moving source of hazard, which can be very large and reach many places on Earth or in orbit. More precisely the hazard study is an analysis that includes a description of all the hazards related to the operation in nominal and accidental operating situations, whether their cause is internal or external. The study specifies the nature and scope of the possible consequences of all these operating situations. When dealing with elements of the launch vehicle which are returned or which fall back and are liable to reach the ground, the study presents the components of these elements, stating their dimensions, masses and materials used. Moreover the study must present an exhaustive analysis of the causes and consequences, as well as the probabilities of the critical events. The mitigations are also defined, if necessary. Since 2010, each new development of a European launch vehicle required a hazard analysis. The lessons learnt consisted in the adaptation of the methodology not only to the scale of the launch system evolution, but also to the different phases or type of development, from a complete launch system to an adaptation for a specific mission. To allow this flexibility, the challenge was to simplify the analysis, without losing from the accuracy and the completeness point of view. The benefit of this approach is to have a more efficient methodology, more widely usable and fruitful all along the development, to anticipate and optimize the mitigation measures.