COLREG Rule 14 — Head-On
When two power-driven vessels meet on reciprocal courses, each shall alter course to starboard.
In practice
Standard alteration to starboard 5-10 degrees when meeting head-on. Both vessels alter; communication via VHF Ch.16 reinforces the manoeuvre.
Regulatory detail & full definition
COLREG Rule 14 — Head-On: '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.' The rule applies when the ships are seeing each other ahead or nearly ahead with mast lights nearly in line and sidelights. When in doubt whether such a situation exists, the vessel shall assume that it does and act accordingly. The required action is mutual — both ships alter to starboard.
Authoritative source: COLREG 1972 ↗
Related
Source: COLREG 1972 Rule 14
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