Hladkyi E. New approaches to the integrated evaluation of flight safety and space-rocket systems reliability

The dissertation defines general problems in evaluating flight safety for launch vehicles (LV) and missile launches in order to increase the safety of space launch system facilities and personnel as well as people living along the line of flight (the described problems are a part of the general issue of ensuring the safety of combat missile systems and space launch systems). Shortcomings of traditional safety evaluation models were analyzed for the cases of LV (missile) normal flight and emergency. For normal flight, the model improvement is related to the consideration of possible fragmentation in areas of separating parts (SP) fall. The developed flight safety evaluation model allow taking into account the prior information on fragmentation of analogue vehicles and the uncertainty of SP initial destruction altitude. For emergency flight, the specifics of flight safety systems (FSS) installed on Yuzhnoye launch vehicles and missiles to identify emergency conditions and emergency engine shutoff (EES) should be taken into account in creating more advanced flight safety evaluation models. The models that are built consider different characteristics of abnormal situations occurring due to a system failure during LV flight and a corresponding FSS reaction to those abnormal situations. Generalization of created models allows taking into account possible EES blocking (first of all, in the initial flight phase) and emergency LV fragmentation in the passive fall phase. Using polygons is proposed for more precise representation of damage areas in safety evaluation models, which significantly increases the adequacy of the developed flight safety models. A number of practical tasks are solved in relation to designing the areas that are dangerous for people, assessing a collective risk for settlements, selecting the ESS blocking time in the initial flight phase, and assessing risks for linear objects. Theoretical questions are considered in relation to the assessment of zero emergency probability for an LV equipped with the FSS that identifies and prevents emergencies and the analysis of influence of this system on the LV basic mission performance. Safety evaluation models are built for the case of testing combat tactical and short-range missiles with cluster warheads on the territory of Ukraine. The enhancement of launch vehicle reliability is one of the basic factors of increasing flight safety. Hence, more advanced models for evaluating the reliability of LV and its stages are built to be applied in different development phases. In particular, these models allow taking into account safety factors applied during design phase and improvements adopted during development tests. Special attention is paid to the parametric reliability and safety models in which it is recommended to use universal lambda-distribution and normal copula on its basis. Key words: launch vehicle, flight safety, abnormal situation, accident, emergency engine shutoff, separating part, individual risk, collective risk, damage area, flight reliability.