American Sailing Quick Guide to Navigation Rules

By: Sailing Tips

It never fails, you are out for a daysail and another vessel decides that the great expanse of ocean is too small and they sail directly at you.  Do you know who has the right of away? Do you understand your responsibilities?

These are the U.S. Coast Guard Inland Navigation Rules that specifically apply to sailing vessels. Navigation rules apply to all vessels and they can be found here:

Sailors who have taken ASA 101 and 103 will have already encountered some of the Steering and Sailing Rules (Part B of the Navigation Rules). ASA 104 requires knowledge of those rules (Rules 4 through 19) and the General Rules (Part A) that define terms and specify how the rules apply. 

The ASA 104 certification does not cover sailing after dark. However, since reduced visibility occurs in rain and fog during daylight hours, all sailors need to know the relevant rules in Part C (lights and shapes) and Part D (sound signals). Thorough knowledge of the Navigation Rules is critical to making safe passages on the water. 

ASA recommends that all sailors study the full rules.

Take a look at these tips from Bareboat Cruising Made Easy, the official manual for ASA 104 Bareboat Cruising Course.

Avoid Collisions  

Note that Rule 2 recognizes that in some circumstances a vessel may have to diverge from the Rules so as to prevent a collision if another vessel doesn’t meet its obligation under the Rules: Everyone is responsible when it comes to avoiding a collision

Rule 2 – Responsibility 

(a) Nothing in these Rules shall exonerate any vessel, or the owner, master, or crew thereof, from the consequences of any neglect to comply with these Rules or of the neglect of any precaution which may be required by the ordinary practice of seamen, or by the special circumstances of the case.

(b) In construing and complying with these Rules due regard shall be had to all dangers of navigation and collision and to any special circumstances, including the limitations of the vessels involved, which may make a departure from these Rules necessary to avoid immediate danger.

It is important to understand that a Sailing Vessel is such only if the sails are up.

Rule 3 – General Definitions

Rule 3b – The term “power-driven vessel” means any vessel propelled by machinery.

Rule 3c – The term “sailing vessel” means any vessel under sail provided that propelling machinery, if fitted, is not being used.

The Lookout Rule

Rule 5 – Lookout

Every vessel shall at all times maintain a proper look-out by sight and hearing as well as by all available means appropriate in the prevailing circumstances and conditions so as to make a full appraisal of the situation and of the risk of collision.

Perhaps the most important rule of all is Rule 5, the “Lookout Rule.”  Everyone on board should be in the habit of being on lookout all the time. As a bonus, while scanning the water for hazards you might see a school of porpoises or a breaching whale.

Rule 6 – Safe Speed 

Every vessel shall at all times proceed at a safe speed so that she can take proper and effective action to avoid collision and be stopped within a distance appropriate to the prevailing circumstances and conditions.

Study the Charts 

Sailboats must not impede vessels restricted by draft to using a marked channel (Rule 9). In some busy areas, Traffi c Separation Schemes keep incoming and outgoing ships apart. Pleasure craft are not obliged to use these “divided highways” if an alternative route is available, and it’s always best to avoid them wherever possible. 

Rule 9 – Narrow Channels 

(a) A vessel proceeding along the course of a narrow channel or fairway shall keep as near to the outer limit of the channel or fairway which lies on her starboard side as is safe and practicable.

(b) A vessel of less than 20 meters in length or a sailing vessel shall not impede the passage of a vessel that can safely navigate only within a narrow channel or fairway.

Rules 12 to 15 establish which vessel, in a situation where the risk of collision exists, is the give-way vessel and which is the stand-on vessel. Rule 16 states that the give-way vessel shall take “early and substantial action to keep clear.” Rule 17 states that the stand-on vessel must maintain its course and speed — unless the give-way vessel fails to meet its obligation to keep clear. 

Note that the rules use the expression “stand on,” not “right of way.” No vessel has the right to collide with a vessel that does not meet its obligations.

Rule 12

Rule 12 – Sailing Vessels 

(a) 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:

  1. 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;
  2. 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;
  3. 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) For the purposes of this Rule, the windward side shall be deemed to be the side opposite 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.

Rule 13

Rule 13 – Overtaking 

(a) Notwithstanding anything contained in the Rules 4-18, any vessel overtaking any other shall keep out of the way of the vessel being overtaken.

(b) A vessel shall be deemed to be overtaking when coming up with a 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) 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) 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.

Rule 14

Rule 14 – Head-on Situation 

(a) ‹‹ 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) 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 and/or both sidelights and by day she observes the corresponding aspect of the other vessel.

(c) When a vessel is in any doubt as to whether such a situation exists she shall assume that it does exist and act accordingly.

Rule 15

Rule 15 – Crossing Situation

(a) When two power-driven vessels are crossing so as to involve risk of collision, the vessel which has the other on her own starboard side shall keep out of the way and shall, if the circumstances of the case admit, avoid crossing ahead of the other vessel.