The article presents a method of defining the required number of substitute technological objects used in the transport system, necessary for correct carrying out of the assigned transport task. The whole of the consideration was presented using the example of a chosen authentic system of the operation of transport means. On the basis of the identification of the authentic transport system and the means of transport operation process carried out in it, crucial operational states were designed as well as the possibilities of transferring between the particular states. Based on that, an event-centered model of the use of the means of transport was built, followed by a mathematical model of that process, assuming that its model is the homogenous Markov process. Then, for operational data obtained from research conducted in the authentic transport system, the values of the analyzed characteristics were defined. The presented results are a result of the research conducted as a part of a larger research project pertaining to the construction of a decision-making model of controlling transport system availability
