Which factors affect a vessel's 'safe speed'?

• A. The color of the hull and the flag.
• B. Visibility, traffic density, maneuverability of other vessels, stopping distance, wind, current, sea state, and draft.
• C. The crew mood and watch schedule.
• D. Weather forecast alone.

Answer: (D)

Safe speed is the speed at which you can take proper and effective action to avoid collisions, given the conditions you face. This includes how far you can see (visibility) so you have time to respond; how busy the area is (traffic density) and how well other vessels can maneuver, which determines how much action you must be prepared to take; your own stopping distance, which grows with speed; and environmental forces such as wind, current, and sea state that affect how quickly you can steer or stop and how the hull handles in different conditions. Draft matters too, because shallow water and propeller or rudder effectiveness can limit maneuverability and increase grounding risk. By contrast, factors like hull color or flag, crew mood or watch schedule, or relying on a weather forecast alone do not determine safe speed. The forecast can inform planning, but safe speed must reflect actual conditions and the ability to react within the available sight, traffic, and maneuvering constraints.