When the give-way vessel does nothing
Stand-on vessel action. Advanced level, about 3 min. COLREGs Rule 17.
The situation
Kestrel, a power-driven vessel, is crossing from your port side on a steady bearing. You are the stand-on vessel and have held your course and speed. You sounded five short blasts; she still shows no sign of altering, and the range is now short.
What do you do now?
- Turn hard to starboard, away from her: Bring her astern and open the distance.
- Keep your course and speed: You are the stand-on vessel.
- Turn to port, toward her stern: Try to pass behind her.
Lookout: A stand-on vessel keeps course and speed at first, but the duty to avoid collision never lapses. Watch for the moment when the other vessel alone can no longer avoid it.
The sound answer
Turn hard to starboard, away from her
Once it is apparent that the give-way vessel is not taking appropriate action, you may act; when collision can no longer be avoided by her action alone, you must. A bold turn to starboard, away from a vessel on your port side, is the authored example here.
Why the other options fall short
Keep your course and speed
Standing on was right at first, but Rule 17(b) requires you to take the action that best aids avoiding collision once she alone cannot avoid it. Holding on at this range leaves the outcome to her.
Turn to port, toward her stern
Rule 17(c): a power-driven vessel acting in a crossing situation should, if the circumstances admit, not alter course to port for a vessel on her own port side. A late starboard turn by her would bring the two of you together.
Rule 17 · Action by stand-on vessel
The stand-on vessel keeps course and speed, may act once the give-way vessel is clearly not doing so, and must act when collision cannot be avoided by the give-way vessel alone. In a crossing situation she avoids turning to port for a vessel on her own port side.