Rule 15. Crossing situation

Actions in a crossing situation are established by Rule 15: When two power-driven vessels are on crossing courses so as to involve risk of collision, the vessel which has the other on its right side shall give way to the other vessel and shall, if the circumstances of the case admit, avoid crossing ahead of the other vessel. Actions of the vessel giving way are established by Rule 16: Every vessel which is required to give way to another vessel shall, so far as possible, take early and substantial action to keep well clear. Actions of the vessel being given way to are established by Rule 17: (a) (i) When one of two vessels is to give way to the other, the other shall keep its course and speed. (ii) However, the latter vessel may take action to avoid collision by its maneuver alone, as soon as it becomes apparent to it that the vessel required to give way is not taking appropriate action in compliance with these Rules. (b) When, for any reason, the vessel required to keep its course and speed finds itself so close that collision cannot be avoided by the action of the give-way vessel alone, it shall take such action as will best aid to avoid collision. (c) A power-driven vessel which takes action in a crossing situation in accordance with subparagraph (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 the left for a vessel on its left side. (d) This Rule does not relieve the give-way vessel of its obligation to keep out of the way.