What is the recommended practice to monitor collision risk in traffic?

• A. Increase speed to outrun others
• B. Maintain course regardless of other vessels
• C. Do nothing in clear weather
• D. Continuously monitor bearing and range to assess risk

Answer: (D)

The main concept here is using relative motion to assess danger. By tracking the other vessel’s bearing (direction to it from your position) and range (distance to it) over time, you can see how its position changes relative to yours. If the bearing stays the same while the range decreases, you’re on a collision course and action is needed. If the bearing changes, you can predict whether a risk is increasing or decreasing and adjust course or speed to create separation. Continuously updating these measurements with all available tools—lookout, radar, AIS—lets you detect threats early and respond in time.

The other options ignore the essential cues of how vessels move relative to each other, either by rushing to outrun without understanding the path of approach, staying on course without considering others, or doing nothing even when visibility or traffic requires vigilance.