subpart ii - conduct of vessels in sight of one another

33 USC 2011 - Application (Rule 11)

Rules in this subpart apply to vessels in sight of one another.

33 USC 2012 - Sailing vessels (Rule 12)

(a) Keeping out of the way 
When two sailing vessels are approaching one another, so as to involve risk of collision, one of them shall keep out of the way of the other as follows:
(i) when each has the wind on a different side, the vessel which has the wind on the port side shall keep out of the way of the other;
(ii) when both have the wind on the same side, the vessel which is to windward shall keep out of the way of the vessel which is to leeward; and
(iii) if a vessel with the wind on the port side sees a vessel to windward and cannot determine with certainty whether the other vessel has the wind on the port or on the starboard side, she shall keep out of the way of the other.
(b) Windward side 
For the purpose of this Rule the windward side shall be deemed to be the side opposite to that on which the mainsail is carried or, in the case of a square-rigged vessel, the side opposite to that on which the largest fore-and-aft sail is carried.

33 USC 2013 - Overtaking (Rule 13)

(a) Overtaking vessel to keep out of the overtaken vessel’s way 
Notwithstanding anything contained in Rules 4 through 18, any vessel overtaking any other shall keep out of the way of the vessel being overtaken.
(b) Overtaking vessel defined 
A vessel shall be deemed to be overtaking when coming up with another vessel from a direction more than 22.5 degrees abaft her beam; that is, in such a position with reference to the vessel she is overtaking, that at night she would be able to see only the sternlight of that vessel but neither of her sidelights.
(c) Assumption that vessel is overtaking another in cases of doubt 
When a vessel is in any doubt as to whether she is overtaking another, she shall assume that this is the case and act accordingly.
(d) Overtaking vessel to become crossing vessel only when finally past and clear 
Any subsequent alteration of the bearing between the two vessels shall not make the overtaking vessel a crossing vessel within the meaning of these Rules or relieve her of the duty of keeping clear of the overtaken vessel until she is finally past and clear.

33 USC 2014 - Head-on situation (Rule 14)

(a) Course alterations to starboard; port side passage 
Unless otherwise agreed, when two power-driven vessels are meeting on reciprocal or nearly reciprocal courses so as to involve risk of collision each shall alter her course to starboard so that each shall pass on the port side of the other.
(b) Existence of head-on situation 
Such a situation shall be deemed to exist when a vessel sees the other ahead or nearly ahead and by night she could see the masthead lights of the other in a line or nearly in a line or both sidelights and by day she observes the corresponding aspect of the other vessel.
(c) Assumption that head-on situation exists in cases of doubt 
When a vessel is in any doubt as to whether such a situation exists she shall assume that it does exist and act accordingly.
(d) Vessel operating on Great Lakes, Western Rivers, or other specified waters, and proceeding downbound with following current 
Notwithstanding paragraph (a) of this Rule, a power-driven vessel operating on the Great Lakes, Western Rivers, or waters specified by the Secretary, and proceeding downbound with a following current shall have the right-of-way over an upbound vessel, shall propose the manner of passage, and shall initiate the maneuvering signals prescribed by Rule 34 (a)(i), as appropriate.

33 USC 2015 - Crossing situation (Rule 15)

(a) Vessel which must keep out of the other vessel’s way 
When two power-driven vessels are crossing so as to involve risk of collision, the vessel which has the other on her starboard side shall keep out of the way and shall, if the circumstances of the case admit, avoid crossing ahead of the other vessel.
(b) Vessels crossing river 
Notwithstanding paragraph (a), on the Great Lakes, Western Rivers, or water specified by the Secretary, a power-driven vessel crossing a river shall keep out of the way of a power-driven vessel ascending or descending the river.

33 USC 2016 - Action by give-way vessel (Rule 16)

Every vessel which is directed to keep out of the way of another vessel shall, so far as possible, take early and substantial action to keep well clear.

33 USC 2017 - Action by stand-on vessel (Rule 17)

(a) Stand-on vessel to keep course and speed; action allowed when give-way vessel fails to take appropriate action 

(i) Where one of two vessels is to keep out of the way, the other shall keep her course and speed.
(ii) The latter vessel may, however, take action to avoid collision by her maneuver 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.
(b) Action by stand-on vessel allowed when action by give-way vessel alone cannot avoid collision 
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.
(c) Crossing situations 
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 port for a vessel on her own port side.
(d) Give-way vessel not relieved of obligation to keep out of the way 
This Rule does not relieve the give-way vessel of her obligation to keep out of the way.

33 USC 2018 - Responsibilities between vessels (Rule 18)

Except where Rules 9, 10, and 13 otherwise require:
(a) Power-driven vessels underway 
A power-driven vessel underway shall keep out of the way of:
(i) a vessel not under command;
(ii) a vessel restricted in her ability to maneuver;
(iii) a vessel engaged in fishing; and
(iv) a sailing vessel.
(b) Sailing vessels underway 
A sailing vessel underway shall keep out of the way of:
(i) a vessel not under command;
(ii) a vessel restricted in her ability to maneuver; and
(iii) a vessel engaged in fishing.
(c) Vessels engaged in fishing when underway 
A vessel engaged in fishing when underway shall, so far as possible, keep out of the way of:
(i) a vessel not under command; and
(ii) a vessel restricted in her ability to maneuver.
(d) Seaplanes on the water 
A seaplane on the water shall, in general, keep well clear of all vessels and avoid impeding their navigation. In circumstances, however, where risk of collision exists, she shall comply with the Rules of this Part.