Technically, under the Rules, there are only three situations whereby one of two vessels while underway can sustain a collision by the other. These three situations are known as: Overtaking, Head-On (or meeting), and Crossing.

For this article, we are going to address the Overtaking situation and follow up with both the Head-On and Crossing situations in future blogs.

Overtaking – for all intent and purposes, one vessel more so in front of another and both traveling in the same direction. The vessel behind chooses to alter course to port or starboard and “pass” the vessel in front of them…hence, overtaking the forward vessel.

Both the International and Inland Rules define Overtaking as follows: (a) Notwithstanding anything contained in the Rules of Part B, Sections 1 and 2, 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 another vessel from a direction more than 22.5 degrees abaft (slightly behind) 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.

In an overtaking situation, there is clearly a Stand-On Vessel and a Give-Way Vessel. Both have specific rules as to their conduct in this situation. The vessel overtaking, or passing the other vessel, is known as the Give-Way Vessel. The vessel being overtaken is known as the Stand-On Vessel.

Action by the Give-Way Vessel is defined in 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 and clear.” The action of the Stand-On Vessel is defined in Rule 17: “(a)(i) Where one of two vessels is to keep out of the way (the Give-Way Vessel), the other (the Stand-On Vessel) 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” 

In an Overtaking situation, the Give-Way Vessel may choose to alter its initial course to port or starboard, which ever seems the most safe and prudent choice, in an effort to begin the maneuver to overtake the Stand-On Vessel. The proper whistle signal is one short blast to starboard or two short blasts to port. Remember, under Inland Rules, the Give-Way Vessel is required to signal its intent, and, must in turn receive an agreement from the Stand-On Vessel before proceeding with the maneuver. The agreement whistle signal will be the same as the initial whistle signal…one short blast from the Stand-On Vessel means it’s okay to overtake me on my starboard side, or two short blasts means it’s okay to overtake me on my port side. Please note, under International Rules (with the exception of Rules 9 & 34(c), this formal agreement by the Stand-On Vessel is not required.

Also, remember that the Stand-On Vessel may signal five short blasts after hearing the initial whistle from the Give-Way Vessel. Five short blasts indicates that the actions or intentions are not understood, or that the other is not taking proper action to avoid a collision, or there is an apparent danger seen by the Stand-On Vessel that may not be seen by the Give-Way Vessel. Five short blasts are commonly known as the danger signal. Should the Stand-On Vessel respond to the Give-Way Vessel with five short blasts after learning of its intent to overtake her, the Give-Way Vessel shall maintain its position until both vessels can reach an agreement.

In summary, an overtaking situation brings two vessels closer together dramatically increasing the risk of collision. The proper use of whistle signals and understanding your role as either the Give-Way or Stand-On vessel is incredibly important to the safety of all concerned.

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Respectfully,

Charles Morris

President and USCG Licensed American Boat Captains, LLC