Rule 16 — Action by Give-Way Vessel
TL;DR — Every vessel directed to keep out of the way must take early and substantial action to keep well clear. That single sentence is the entire text of the rule, and every word in it is exam-tested. 33 CFR §83.16
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What the Rule Says
The full text of Inland Rule 16 reads:
"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."
That is it — one sentence. But unpacking each operative phrase reveals exactly what the exam will probe.
"Every vessel which is directed to keep out of the way"
Rule 16 does not create the obligation to give way; it governs how a vessel fulfills an obligation that other rules have already assigned. The rules that assign give-way status include, among others:
- Crossing situations: the vessel that has the other on her own starboard side is the give-way vessel. 33 CFR §83.15
- Western Rivers / Great Lakes crossing rule: a power-driven vessel crossing a river keeps out of the way of a vessel ascending or descending the river. 33 CFR §83.15
The phrase "every vessel" is deliberately broad. It does not matter whether the give-way vessel is a power-driven vessel, a sailing vessel, or any other category — once a rule assigns give-way status, Rule 16 dictates the standard of conduct. 33 CFR §83.16
"So far as possible"
This qualifier acknowledges that some vessels are constrained in their ability to maneuver — for example, a vessel not under command, which through some exceptional circumstance is unable to maneuver as required by the Rules 33 CFR §83.03 — but it does not excuse a give-way vessel from acting. It means the give-way vessel must do everything within its actual capability. A vessel that can maneuver has no shelter under this phrase.
"Early"
Timing is the first dimension of compliance. Action must be taken while there is still ample sea room and time for the maneuver to be effective. This aligns directly with the general collision-avoidance standard: any action to avoid collision shall, if circumstances admit, be positive, made in ample time, and with due regard to good seamanship. 33 CFR §83.08 Waiting until the vessels are close aboard before altering course is a violation of both Rule 8 and Rule 16.
"Substantial"
The second dimension is magnitude. Any alteration of course and/or speed shall, if circumstances admit, be large enough to be readily apparent to another vessel observing visually or by radar. A succession of small alterations of course and/or speed should be avoided. 33 CFR §83.08 A 5-degree course change that is invisible on another vessel's radar display is not substantial. A 60-degree course alteration that opens the CPA to a safe distance is.
"To keep well clear"
The goal is not merely to avoid collision — it is to keep well clear, meaning the give-way vessel must open the passing distance to a genuinely safe margin, not just scrape by. Action taken to avoid collision shall be such as to result in passing at a safe distance, and the effectiveness of the action shall be carefully checked until the other vessel is finally past and clear. 33 CFR §83.08
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Why It Matters on the Exam
Rule 16 Is the "How" to Other Rules' "Who"
Exam questions frequently present a scenario — two power-driven vessels crossing, for example — and ask what the give-way vessel is required to do. The answer always traces back to Rule 16: take early and substantial action to keep well clear. 33 CFR §83.16 Candidates who only memorize which vessel gives way, without knowing the standard of conduct, will miss the follow-on question.
The Crossing Rule Feeds Directly Into Rule 16
In a crossing situation between two power-driven vessels, the vessel with the other on her starboard side keeps out of the way and, if circumstances admit, avoids crossing ahead of the other vessel. 33 CFR §83.15 Once that give-way obligation is established, Rule 16 governs the execution. Exam questions may ask: "What action is required of the give-way vessel?" The answer must include the words early, substantial, and well clear — all drawn from the rule text itself. 33 CFR §83.16
Rule 16 Does Not Disappear When Rule 17 Kicks In
A common exam trap: once the stand-on vessel takes independent action under Rule 17(a)(ii) — because the give-way vessel is not acting — does the give-way vessel's obligation evaporate? No. Rule 17 explicitly states that it does not relieve the give-way vessel of her obligation to keep out of the way. 33 CFR §83.17 Both vessels may be maneuvering simultaneously, but the give-way vessel remains bound by Rule 16 throughout.
The Stand-On Vessel's Constraints Reflect the Give-Way Vessel's Duty
Rule 17 permits the stand-on vessel to take action by her maneuver alone as soon as it becomes apparent that the give-way vessel is not taking appropriate action. 33 CFR §83.17 The trigger for that permission is the give-way vessel's failure to comply with Rule 16. Understanding Rule 16 therefore also explains when Rule 17(a)(ii) becomes available to the stand-on vessel.
Speed Reduction Is a Valid Give-Way Action
Candidates sometimes assume that only a course alteration satisfies Rule 16. The Rules are clear that if necessary to avoid collision or allow more time to assess the situation, a vessel shall slacken her speed or take all way off by stopping or reversing her means of propulsion. 33 CFR §83.08 Slowing down, stopping, or backing is a legitimate — and sometimes the most appropriate — give-way maneuver.
The Western Rivers / Great Lakes Crossing Exception
On the Great Lakes, Western Rivers, or waters specified by the Secretary, a power-driven vessel crossing a river keeps out of the way of a power-driven vessel ascending or descending the river. 33 CFR §83.15 This is a departure from the standard starboard-side crossing rule. Once that give-way obligation is assigned, Rule 16's standard of early and substantial action applies identically. Exam questions set on the Mississippi River or the Great Lakes may test whether candidates know this exception and can then apply Rule 16 correctly to the crossing vessel.
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Common Pitfalls
1. Confusing "avoid collision" with "keep well clear." Rule 16 sets a higher bar than merely not colliding. The give-way vessel must keep well clear — a comfortable, unambiguous margin — not just achieve a near-miss. 33 CFR §83.16
2. Making small, incremental course changes. A succession of small alterations should be avoided. 33 CFR §83.08 Candidates sometimes think that any course change satisfies the rule. It does not unless it is large enough to be readily apparent to the other vessel observing visually or by radar. 33 CFR §83.08
3. Acting too late. "Early" means well before the situation becomes a close-quarters emergency. Waiting until the stand-on vessel has already taken evasive action is too late to satisfy Rule 16. 33 CFR §83.16
4. Believing the give-way obligation ends when the stand-on vessel maneuvers. Rule 17(d) is unambiguous: the stand-on vessel's action does not relieve the give-way vessel of her obligation. 33 CFR §83.17
5. Forgetting that "vessel" is a broad term. "Every vessel" in Rule 16 covers any watercraft used or capable of being used as a means of transportation on water, including non-displacement craft, WIG craft, and seaplanes. 33 CFR §83.03 The rule is not limited to power-driven vessels.
6. Overlooking speed reduction as a valid maneuver. Stopping or reversing is explicitly authorized as a collision-avoidance action. 33 CFR §83.08 Do not assume that only a course alteration satisfies the give-way obligation.
7. Misapplying the crossing rule on Western Rivers. On the Western Rivers and Great Lakes, the vessel crossing the river gives way to the vessel ascending or descending — regardless of which side the other vessel is on. 33 CFR §83.15 Applying the standard starboard-side rule in this context is a common error.
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Quick Check
Q1 — What is the complete standard of conduct imposed on a give-way vessel by Rule 16?
The give-way vessel shall, so far as possible, take early and substantial action to keep well clear. 33 CFR §83.16
Q2 — In a crossing situation, which vessel is the give-way vessel, and what additional guidance does Rule 15 provide about how she should maneuver?
The vessel that has the other on her own starboard side is the give-way vessel. Rule 15 further specifies that she shall, if circumstances admit, avoid crossing ahead of the other vessel. 33 CFR §83.15 She then executes that obligation per Rule 16: early and substantial action to keep well clear. 33 CFR §83.16
Q3 — The stand-on vessel has taken independent action under Rule 17(a)(ii) because the give-way vessel appeared not to be acting. Is the give-way vessel now relieved of her Rule 16 obligation?
No. Rule 17 explicitly states that it does not relieve the give-way vessel of her obligation to keep out of the way. 33 CFR §83.17 Both vessels may be maneuvering simultaneously; the give-way vessel remains bound by Rule 16. 33 CFR §83.16
Q4 — A power-driven vessel on the Mississippi River is crossing the channel. A tow is descending the river. Which vessel is the give-way vessel, and why?
The crossing vessel is the give-way vessel. On the Western Rivers, a power-driven vessel crossing a river shall keep out of the way of a power-driven vessel ascending or descending the river — regardless of which side the descending vessel is on. 33 CFR §83.15 The crossing vessel must then take early and substantial action to keep well clear. 33 CFR §83.16
Q5 — Is a course alteration the only action that satisfies Rule 16? What else is permitted?
No. A vessel may also slacken speed, take all way off by stopping, or reverse her means of propulsion if necessary to avoid collision or allow more time to assess the situation. 33 CFR §83.08 Any action taken must still be early, substantial, and result in passing at a safe distance. 33 CFR §83.08 33 CFR §83.16
Q6 — Why should a give-way vessel avoid making a series of small course changes rather than one large alteration?
A succession of small alterations of course and/or speed should be avoided. Any alteration shall be large enough to be readily apparent to another vessel observing visually or by radar. 33 CFR §83.08 Small incremental changes may not be detectable by the stand-on vessel and do not constitute the "substantial" action required by Rule 16. 33 CFR §83.16