Action by Stand-on Vessel
The stand-on vessel shall keep her course and speed, but may take action when it becomes apparent the give-way vessel is not acting.
Rule 17 defines the obligations of the stand-on vessel.
- 1Where one vessel is required to keep out of the way, the other shall keep her course and speed.
- 1The stand-on vessel may however take action to avoid collision by her manoeuvre alone, as soon as it becomes apparent to her that the vessel required to keep out of the way is not taking appropriate action.
STCW Bridge Watch Lens
Decide applicability before manoeuvring: Rules 4-10 apply in any visibility, Rules 11-18 only when vessels are in sight, and Rule 19 governs radar-only encounters in restricted visibility.
Build the traffic picture with sight, hearing, radar/ARPA and chart context. Do not let AIS or one isolated bearing replace systematic observation.
After manoeuvring, keep monitoring bearing, range, CPA/TCPA and passing distance until the other vessel is finally past and clear.
Exam Focus
Identify the vessel types first, then the relative bearing, then whether one vessel is overtaking. Misclassifying the encounter is the usual exam failure.
If two rules seem to conflict, check the order carefully: overtaking duties still apply, and Rule 2 still requires ordinary seamanship.
Key Takeaways
Stand-on vessel initially maintains course and speed
May take avoiding action if give-way vessel fails to act
MUST act if collision cannot be avoided by give-way vessel alone
In crossing, do not alter to port for a vessel on your port side
Common Mistakes
Stand-on vessel altering course too early, confusing the give-way vessel
Failing to take action when the give-way vessel clearly is not acting
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