Action by stand-on vessel
In plain language
The stand-on vessel shall keep her course and speed. She may take action as soon as it becomes apparent the give-way vessel is not taking appropriate action, and shall take action when collision cannot be avoided by the give-way vessel alone.
Full text of Rule 17
Where one of two vessels is to keep out of the way the other shall keep her course and speed.
The latter 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 in compliance with these Rules.
When, from any cause, the vessel required to keep her course and speed finds herself so close that collision cannot be avoided by the action of the give-way vessel alone, she shall take such action as will best aid to avoid collision.
A power-driven vessel which takes action in a crossing situation in accordance with sub-paragraph (a)(ii) of this Rule to avoid collision with another power-driven vessel shall, if the circumstances of the case admit, not alter course to port for a vessel on her own port side.
This Rule does not relieve the give-way vessel of her obligation to keep out of the way.
Reproduced from the COLREGs 1972 (as amended) for study. Always verify against the official IMO publication.
Key points
- 1
Stand-on means maintain course and speed — not stand still and do nothing.
- 2
You may act when the give-way vessel clearly is not acting.
- 3
You must act when collision can no longer be avoided by the give-way vessel alone.
- 4
A stand-on alteration should avoid port turns for a vessel on her own port side.