This article presents the structure of a model of the allocation of radiocommunication events at coastal radio stations, land-based satellite stations and on vessels in sea area A3. The propagation of radio waves in the HF band has been analyzed to examine the range of various radio stations and their capabilities of establishing communication between each other. We also present methods of modeling and displaying the deployment of individual stations, of presenting radiocommunication events as a function of time using time diagrams, as well as the manner of the chronological presentation of radiocommunication events and related decisions. It has been shown that there is a relationship between the effectiveness of communication and propagation conditions that is strongly dependent on the time-of-day. We present the need to develop a decision support system for the radio operator on the bridge.