Aerospace Technic and Technology

The subject matter of the article is an analysis of methods for assessing the reliability of a complex technical system applicable to a rocket engine for solving the problem of estimating the reliability of a rocket engine at an early stage of its development. The goal is to determine the method of estimating the reliability of a rocket engine with insufficient statistical information. The tasks to be solved: to carry out the analysis of existing methods for assessing the reliability of a complex technical system; to justify the expediency of their application for assessing the reliability of the rocket engine at an early stage of its development; choose an effective method for solving the problem. In work the analysis of following methods was carried out: a method of rationing reliability taking into account the complexity of the system and the importance of the elements belonging to the system; method of "weighting factors"; method of accounting for a priori information when using the model "parameter – one-way tolerance field". The following results obtained during the research. As a result of the analysis of existing methods for assessing the reliability of a complex technical system, it argues that they can apply to a rocket engine in terms of the availability of sufficient information When determining the method for estimating the reliability of a rocket engine with insufficient statistical information, a reliability chosen model that allows estimating the level of reliability of a rocket engine at an early stage of its development with insufficient information.  Conclusions. The scientific novelty of the results is following: the proposed method makes it possible to assess the level of reliability of rocket engines of new developments when the designers do not have sufficient statistical information on the results of reliability tests, that is, at the very beginning of the development of the rocket engine; developed methods for assessing reliability of a complex technical system applied to a rocket engine with the use of the "parameter – one-way tolerance field" model was further developed, thanks to the availability of a priori information, which makes it possible to use them for various approaches to assess the reliability of a rocket engine, depending on the amount of information available

valuation methods; mathematical expectation; rocket engine; failure; reliability evaluation; reliability function; "weighting factor"

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