Official rule text as published in the U.S. Coast Guard Navigation Rules
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.
MyCOLREGS explanation
Summary
Rule 5 requires every vessel, at all times, to keep a proper lookout — using sight, hearing, and any other available means suited to the conditions, such as radar or AIS. The duty is continuous and multi-sensory: it is not satisfied by glancing forward occasionally, and electronics supplement it rather than replace it. The goal is a full, current appraisal of the situation and of collision risk, in every condition of visibility.
Real World Example
Failure to maintain a proper lookout is one of the most commonly cited faults in collision investigations - more accidents trace back to nobody actually looking and listening than to anyone misjudging a maneuver once the danger was already spotted.
Practice Questions
Q1. You are running at night with radar and AIS both displaying no nearby targets. Does that alone satisfy Rule 5's lookout requirement?
A. Yes, as long as the autopilot is engaged, since an active autopilot is treated as satisfying the lookout requirement automatically.
B. No — Rule 5 requires a dedicated crew member with no other duties on every vessel regardless of size.
C. No — Rule 5 requires a lookout by sight and hearing as well as by all available means; electronics supplement but do not replace a human keeping watch.
D. Yes — electronics are "all available means," so nothing more is required.
Q2. A helmsman keeps his eyes locked on the chartplotter's route line the entire watch, glancing up only occasionally. He's technically "keeping watch" the whole time. Does this satisfy Rule 5?
A. Yes - as long as his eyes are open and pointed generally forward, Rule 5 is satisfied regardless of what he's actually looking at or whether he'd notice a genuine hazard developing.
B. No, but only because he is alone at the helm; the same fixed-screen habit would fully satisfy Rule 5 as long as a second crew member happened to be aboard as well.
C. Yes, because Rule 5 only requires a chartplotter or radar display to be monitored, not the water itself, since electronic instruments are considered a superior substitute for a human lookout.
D. No - Rule 5 requires a lookout aimed at making a full appraisal of the situation and risk of collision, which a helmsman fixated on a screen instead of the water around him isn't actually doing.
Practice Question Answers
Q1.
C. No — Rule 5 requires a lookout by sight and hearing as well as by all available means; electronics supplement but do not replace a human keeping watch. Rule 5's text requires sight and hearing "as well as" all available means appropriate to the circumstances — the electronics are additive, not a substitute for a human watch, and Rule 5 does not mandate a dedicated lookout position on every vessel regardless of size. A brings in something (autopilot) that has nothing to do with keeping a lookout. B overstates the rule - Rule 5 doesn't mandate a dedicated, single-purpose crew member on every vessel regardless of size. D is the exact assumption Rule 5 is written to prevent: that electronics alone satisfy the duty.
Q2.
D. To make a full appraisal of the situation and of the risk of collision. Rule 5 states the lookout duty exists so as to make a full appraisal of the situation and of the risk of collision — it is directly tied to collision avoidance, not a general administrative requirement. A and C each shrink the purpose of a lookout down to something administrative or narrow - open eyes, or an electronic display - ignoring Rule 5's own broader text. B reaches the right conclusion for the wrong reason, tying it to crew count rather than what the lookout is actually doing.