The objective of the CADMUSS project is three-fold.
Firstly, to develop safety criterion for safe passage in ship-ship encounters in high seas and coastal areas.
Secondly, to implement the criterion within Decision Support Tools (DSTs) for onboard and ashore use respectively. Therefore supporting process of collision avoidance from the perspective of the ship as well as shore-based centers, such as Vessel Traffic Services (VTS) and Fleet Operation Centres (FOC).
Thirdly, to provide solid grounds for transferability of the concept into strategic risk assessment field, so the safety criterion can be used to evaluate the level of accidental risk for a given sea area as well as for post-process risk profiling of individual vessels and voyages.
The safety criterion will delineate the area required for a ship to perform safe and effective collision and grounding avoidance maneuver in the high seas, as well as the time of its execution. The area will be bound by the outer and inner zones.
The outer zone refers to the comfort area of a navigator, within which the navigator performs an evasive maneuver that are well known and frequently practiced in a daily routine, thus can be considered safe. The outer zone will be evaluated in the course of experts’ knowledge elicitation process. To this end questionnaires, structured interviews, sessions with experts in full mission bridge simulator will be adopted.
The inner zone refers to the minimum yet safe distance between own ship and an obstacle, that stems from the ship hydrodynamics, geometry of the encounter and hydrometeorological conditions. Moreover, the inner zone is also gradual as it depends on the type of evasive maneuver. Therefore it conceptually and practically differs from the so called last-chance manoeuver, which is associated with large rudder deflection angle at high speed, where the performance of a crew that already acts under high pressure may be reduced, thus the quality and effectiveness of such manoeuver may deteriorate. Additionally ship stability and environmental conditions may not allow for that type of manoeuver in a given situation. Thus, the last-chance manoeuver cannot be seen as fully safe neither for ship, cargo nor the crew.
The inner zone serves as the boundary for the own ship safe manoeuvering area, which if infringed by an object on a collision course leads to an accident.
By linking the experts’ knowledge with ship’s hydrodynamics in the definition of the safety criterion, we aim to provide the navigator clear and unambiguous message on the available time and distance in a given encounter to perform safe and effective evasive action. To this end we apply the criterion in two types of DSTs. First in the ship-based navigational DST. Second in the shore-based maritime traffic surveillance and management services i.e. VTS, FOC applying e-Navigation infrastructures with enhanced facilities for data exchange.