109 https://doi.org/10.31713/m907 RESOURCE-SAVING AND RELIABILITY OF TRANSPORTATION SYSTEMS Tkhoruk Е.І. National University of Water and Environmental Engineering (NUWEE), Associate Professor, Candidate of Technical Science, Associate Professor, Department of Transport Technologies and Technical Service, Ukraine Krystopchuk M.Е. National University of Water and Environmental Engineering (NUWEE), Associate Professor, Candidate of Technical Science, Associate Professor, Department of Transport Technologies and Technical Service, Ukraine Soroka V.S. National University of Water and Environmental Engineering (NUWEE), Associate Professor, Candidate of Agricultural Sciences, Associate Professor, Department of Transport Technologies and Technical Service, Ukraine Holotiuk M.V. National University of Water and Environmental Engineering (NUWEE), Associate Professor, Candidate of Technical Science, Associate Professor, Department of Transport Technologies and Technical Service, Ukraine Abstract The article is based on the analysis of the development of the theory of reliability and its indicators are formulated indicators of the reliability of transport systems and built a system of factors determining their reliability. It is established that the for- mation of the theory of reliability of transport systems today is not completed. Based on the specifics of the systems, new reliability indicators were proposed and substan- tiated such as emergency downtime and reliability of emergency downtime. On the basis of the performed studies, it was found that the specifics of the transport process require the introduction of emergency downtime close to the recovery time and the reliability of emergency downtime. It is necessary the introduction of two close pa- rameters such as the average recovery time and the average emergency idle time. They are associated with the need to distinguish between the idle time of a techno- logical system or a separate element when a failure occurs and the idle time is need-