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functionalities carried out in this phase with regard to the original set track (Result of voyage planning, 
Section 2) represent a plan change in a local area and the execution of this change. 
5.1.2 Functionalities 
In accordance with the division into a planning phase and an executing phase, undertaken for tasks in 
this area, the following classification may be produced for the functionalities of the task “collision avoid 
ance": 
1. Planning the evasion manoeuvre: 
1.1 Collect information for manoeuvre planning: assessing the current traffic situation, 
assessing the present encounter situation, determining the present scope for 
executing evasion manoeuvres, determining action times. 
1.2 Stipulate evasion manoeuvre: determining an evasion manoeuvre which clarifies 
the present encounter situation bearing in mind hydrographic boundary conditions 
and the traffic situation, and corresponds to the regulations for collision avoidance 
and those of “good seamanship”. An evasion manoeuvre in this context may be 
a change in course and/or speed. 
1.3 Plan evasion track: planning the evasion track: place and time of Initiation of the 
evasion manoeuvre; course changing points, if deviation by course change is en 
visaged; place and time of resumption of the original planning. 
2. Monitoring and following the evasion track: 
2.1 Follow evasion track: executing the stipulated changes in course and speed at the 
corresponding planned times. 
2.2 Monitor evasion track: monitoring the planned changes in course and speed as 
well as the stipulated times for leaving and resuming the original planning. Fur 
thermore, the actual effect of the planned evasion manoeuvre must be monitored 
in the course of this functionality. Two aspects are of importance here: 
• Does the executed manoeuvre clarify the encounter situation in the intended 
manner? 
• Does the manoeuvre entail other critical situations (with regard to other for 
eign vessels or fixed objects)? 
2.3 Monitoring effectiveness of the evasion manoeuvre. The evasion manoeuvres 
stipulated in Functionality 1.2 and the resultant evasion track were made on the 
basis of assumptions with regard to the behaviour of the other traffic participants 
recorded in the sea area. Since the actual behaviour may deviate from this, the 
effectiveness of the manoeuvre as well as possible side-effects (e.g. threat to 
other vessels) must be constantly checked. 
5.1.3 Functions 
Since the process of collision avoidance comprises the planning, monitoring and following of evasion 
tracks, the functionalities itemised in the previous section are distinguished in terms of type, depending 
on the phase of the process.