Search

One of the components necessary to determine the width of a safe maneuvering area on two-way fairways is a safe passing distance. Existing methods do not consider modern model studies of interactions between passing vessels, additionally, they ignore the influence of the vessel’s position accuracy and navigators’ qualifications. This paper presents a method to determine the passing distance, which is free of the drawbacks of the methods used so far. The proposed method is based on simulation research carried out using an FMBS-type (Full Mission Bridge) simulator. The tests were carried out for three loaded vessels (bulk carrier, tanker, and sea ferry), on four sections of the fairway with different parameters and aids-to-navigation available. The results obtained allowed the modification of the authors’ previous, but still widely used, deterministic–probabilistic MTE (Marine Traffic Engineering) method for determining the width of a safe maneuvering area.

Context: From the perspective of marine traffic engineering, a system of port waterways is composed of a set of waterways (port areas), such as approach channels, port entrance, inner fairways (port channels, rivers, lakes), turning basins and port basins of various terminals. The sea waterway must be adjusted to the navigation of specific types of ships, characterized by length, breadth, draft and airdraft. The primary requirement for shipping in sea waterways is the safety of navigation. Each sea waterway has traffic restrictions for the ships using it. These restrictions are called conditions of sea waterway operation or conditions of ship operation in the sea waterway. Problem: There are a number of empirical, deterministic or probabilistic methods to determine the safe width of maneuvering areas on port waterways. The direct application of empirical methods to determine the conditions for the safe operation of ships on the complex waterway, such as the Świnoujście–Szczecin fairway, was impossible due to the complexity of the waterway and various restrictions on its individual parts. Method: The paper presents the assumptions and calculation procedure of a method allowing for the determination of maximum safe parameters of ships in existing complex waterways. Results: The proposed method was used in the preparation of port regulations for the dredged and widened Świnoujście–Szczecin waterway. The results of these calculations are presented as a practical application of the method. Conclusions: This article defines conditions for the safe operation of ships in complex port waterways systems and presents the methodology for determining maximum safe parameters of ships in existing complex port waterways systems.

A paper presents problems related to the safe operation of wind turbine installation vessels in port waterways. It presents a developed method for determining maximum safe lengths of blades of wind turbines loaded transversely on a jack-up vessel leaving a given port. In this method, the safety criterion for navigation is the acceptable risk of accidents, whose scenarios are determined by the identification of hazards in the studied waterway. Based on this safety criterion, the confidence level of the width of the safe maneuvering area of the loaded jack-up vessel and the maximum safe lengths of the transversely loaded wind turbine blades, respectively, are determined.

Perhaps the most problematic issue regarding navigation safety management is the unknown, or unknowable, is the navigator’s decision made in the face of a dangerous situation. This applies particularly to collision-avoidance. The aim of the article is to identify factors that influence the moment of decision during a collision-avoidance manoeuvre and to define theoretical distributions that can be used during modelling of a navigator’s behaviour. The applicable research was divided into two stages. In the first, the distance between ships and the time to closest point of approach (TCPA) were analysed. In the second, the influence of the size of the target ships and relative speed were investigated. The advantage of the paper is its use of actual observations collected in real situations. The proposed approach allows for a better understanding of the navigator’s actual decision-making, which will be instructive in measures taken to improve navigational safety.

The paper presents the results of a study on improving the safety of navigation, during maneuvers in restricted areas, with the use of an augmented virtuality navigation information display. The augmented virtuality solution has been developed by one of the authors and has been described in a previous paper. A set of simulation scenarios has been proposed to study various maneuvers with different types of ships. Models of existing areas and existing ships have been used so the study can be recreated and reevaluated with different types of interfaces. The study is focused on comparing safe maneuvering areas with different information sources used. The results showed that augmented virtuality solution can indeed decrease the safe maneuvering areas and thus increase the safety of navigation for maneuvers in restricted areas.