If the stand-on vessel observes the other vessel failing to take action, what may it do?

• A. Continue on current course and hope the other vessel acts.
• B. Wait for a different signal from the other vessel.
• C. Take action to avoid.
• D. Ask the other vessel to clarify intent.

Answer: (C)

When the stand-on vessel sees that the other vessel is not taking action to avoid, it may and must take action to avoid collision. The purpose of this rule is to prevent a collision even if the other vessel is not complying. So, if ROM (risk of collision) exists, you should maneuver to pass clear—altering course, adjusting speed, or both as needed. Relying on the other vessel to act would risk a collision, and waiting for a different signal or asking for clarification does not address the immediate danger. Early, decisive action to avoid is the correct approach.