Official rule text as published in the U.S. Coast Guard Navigation Rules
(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.
| Inland |
|---|
| (d) Notwithstanding Rule 14(a), 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. |
Color note: black text applies generally; blue is International Waters; green is Inland Waters.
MyCOLREGS explanation
Summary
When two power-driven vessels are heading toward each other on reciprocal or near-reciprocal courses, each one turns to starboard so they pass port-to-port — unless, on inland waters, they've agreed on a different plan. If you're not sure whether it's really a head-on situation, treat it as one. On the Great Lakes, Western Rivers, and other Secretary-specified waters, a boat running downbound with the current has the right-of-way over one heading upbound, and must propose how to pass and start the whistle signals.
Real World Example
Both vessels turning to starboard works precisely because it needs no communication or agreement in the moment - if either boat guessed differently and turned to port instead, two safe evasive turns would combine into a collision course. That's also why waiting for dead-certain confirmation before turning is dangerous: by the time a borderline head-on situation becomes unmistakable, the distance needed for an early, easily-seen course change may already be gone.
Practice Questions
Q1. Two power-driven vessels are meeting head-on in open water. What is the normal maneuver?
A. Each vessel alters course to port, so they pass starboard-to-starboard.
B. The faster vessel holds course; the slower vessel gives way.
C. Each vessel alters course to starboard, so they pass port-to-port.
D. Both vessels stop and wait for radio contact.
Q2. You see a vessel ahead at night but you're not sure her lights line up closely enough to call it a true head-on meeting under Rule 14(b). What does Rule 14(c) require?
A. Assume it is a crossing situation instead, since that is more common.
B. Assume a head-on situation exists and act accordingly.
C. Do nothing until the range closes to less than one mile.
D. Wait for radio confirmation of her course before acting.
Practice Question Answers
Q1.
C. Each vessel alters course to starboard, so they pass port-to-port. Rule 14(a) requires each vessel to turn to starboard in a head-on meeting so they pass port-to-port. A has the turn direction backwards - turning to port would create a starboard-to-starboard pass, not the intended port-to-port. B substitutes speed for the actual rule. D substitutes communication for the required maneuver.
Q2.
B. Assume a head-on situation exists and act accordingly. Rule 14(c) resolves doubt in favor of caution: when unsure whether a head-on situation exists, assume that it does and act accordingly. A gets the default backwards - when in doubt, Rule 14(c) says assume head-on, not crossing. C invents a distance threshold. D substitutes radio confirmation for the rule's instruction to act on the assumption now.