What signaling is commonly used to indicate a vessel is altering course to port or starboard?

• A. Visual and audible signals consistent with the Rules.
• B. Hand signals only.
• C. Verbal radio communications only.
• D. Signals are optional and not standardized.

Answer: (A)

Changing course is communicated using standardized signals that are part of the Rules. The most common method is a combination of audible and visual signals that other vessels recognize. Specifically, a short blast indicates an intention to alter course to the starboard, while two short blasts indicate an intention to alter course to the port. These signals are universally understood and are reinforced by any applicable visual indicators, such as lights or shapes when appropriate. Verbal radio calls or hand signals can supplement, but the official signaling practiced at sea is the visual and audible signals described by the Rules, not optional or nonstandard methods.