What should a vessel do if a fog signal is heard forward of the beam?

When a vessel hears a fog signal ahead of the beam, it indicates that another vessel or obstacle may be within close proximity and potentially on a collision course. The appropriate action in this situation is to reduce speed to bare steerage way. This means slowing down enough to maintain control of the vessel without losing maneuverability, which is crucial in foggy conditions where visibility is severely reduced.

Reducing speed allows for more time to assess the situation, make any necessary navigational decisions, and respond effectively to any unforeseen obstacles or vessels that may appear. It helps prevent collisions, which are more likely to occur in such low visibility conditions. The emphasis on bare steerage way means the vessel remains manageable and can be easily navigated, even while operating at a lower speed.

While maintaining full speed could lead to a dangerous situation if an obstacle is encountered, and increasing speed would similarly reduce reaction time and control, changing course immediately without a thorough assessment might lead to unexpected navigational hazards, particularly in fog. Thus, reducing speed to bare steerage way is the safest and most prudent response in this scenario.