Lesson previewClassify the Traffic Situation Before Acting1 section shown
Preview lesson
Classify the Traffic Situation Before Acting
What you will learn
Distinguish meeting, crossing, overtaking and harbour or tributary movements, then identify the scope and waterway controls that govern the decision.
The safest first question is not 'who has priority?' It is 'what situation is developing, which rule family applies, and is there unquestionably enough water for it?'
CEVNI defines meeting as vessels on directly or almost directly opposite courses. Overtaking begins when a vessel comes up from more than 22.5 degrees abaft the other vessel's beam. A crossing situation is an approach that is neither meeting nor overtaking. Entering or leaving a harbour or tributary, leaving a berth and turning have their own provisions, so a general crossing slogan cannot replace the correct rule family.
Article 6.03 permits meeting or overtaking only when the fairway is unquestionably wide enough for simultaneous passage, after accounting for local circumstances and the movements of other vessels. Width is therefore more than the visible gap between hulls: depth, current, bend, bridge opening, moorings, wash, convoy geometry and escape water all matter.
Scope matters as much as geometry. CEVNI contains explicit small-craft rules and exclusions, while national or river rules can vary meeting and overtaking procedure. Read the signs, current traffic control and actual vessel constraints before translating one rule into an action.
Traffic decision reader
Compare the situation, rule family, action and boundary before deciding which vessel moves.
Plan view · arrows show travel
Situation
Two motorised small craft meet head-on in open, adequate water.
Governing rule
For two small craft, each veers to starboard so they pass port side to port side.
Safe action
Make the alteration early, keep it obvious and confirm that the other vessel's movement agrees.
Boundary
Do not transfer the commercial upstream/downstream exchange to small craft without checking its scope.
Classify the situation and its boundary before deciding which vessel moves.
Worked example
A faster vessel is closing from 30 degrees abaft your starboard beam as both craft approach a bridge reach.
- 1Thirty degrees abaft the beam is more than the 22.5-degree boundary, so classify this as overtaking rather than crossing.
- 2Check the bridge reach, signs, oncoming traffic, depth and available abort water before considering a side.
- 3If the whole pass is not unquestionably safe, remain in sequence; a momentary gap does not satisfy the rule.
Sense check: Changing the label from crossing to overtaking also changes who must prove the manoeuvre safe and which exchange may apply.
| Observed geometry | Rule family to open | First control question |
|---|---|---|
| Directly or almost opposite courses | Meeting | Normal, narrow-fairway or sign-controlled procedure? |
| Other vessel more than 22.5° abaft the beam | Overtaking | Can the whole pass be completed without danger? |
| Approach is neither meeting nor overtaking | Crossing | Which vessel, fairway boundary or special manoeuvre changes the rule? |
| Entering, leaving, crossing after leaving or turning | Harbour / tributary / turning | Will established traffic have to change abruptly? |
Run a four-part traffic scan
You see a commercial vessel, a bend and a side-waterway entrance within the same short reach.
1. Classify
Name the developing geometry: meeting, crossing, overtaking or a harbour/tributary movement.
2. Control
Read fairway marks, prohibitions, traffic lights, radio or authority instructions and local rules.
3. Scope
Identify small craft, convoys, high-speed craft and vessels constrained by the waterway.
4. Space
Prove that the complete manoeuvre and a safe abort fit before committing.
Sense check: If you cannot name the situation or prove the space, slow or hold while the picture becomes clear.
Common mistake or limitation
- Using 'the larger vessel has priority' as a substitute for classifying the situation and applying the small-craft scope rule.
- Treating the first open patch of water as proof that a complete meeting or overtake is safe.
- Applying ordinary crossing rules to a harbour departure, turn or marked fairway-boundary situation.
Recap
- Meeting, crossing, overtaking and harbour movements are different rule families.
- The whole manoeuvre, not its first seconds, must fit the waterway safely.
- Geometry, scope, control and available water should agree before action begins.
Optional quick check
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