Operating in fog can be stressful and requires absolute attention to the vessel and your surroundings. A recent case study may help. The idea is for you to imagine yourself as the watch officer — you’re underway in the early morning doing 12 knots when you enter heavy fog off Massachusetts. You notice other vessels on radar with the nearest about four miles away and it appears the vessel is on a reciprocal course doing about the same speed.
You continue with your watch duties — taking a position fix, entering data into the ship’s log, and looking at your next waypoint course change. The alarm on the Automatic Radar Plotting Aids (ARPA) sounds and you look up, the other vessel has made a course and speed change, and now the possibility of a collision exists. The fog is heavier, and you cannot get a visual on the vessel or see any lights, but radar shows it forward of your starboard beam.
Many times, reducing speed is the only action required to avoid a collision.
You attempt to hail them on the VHF radio but there is no answer, so you call the captain to come to the bridge. At this point, the Closest Point of Approach (CPA) is now 0.0 miles and a Time to Closest Point of Approach (TCPA) is one minute — you turn the vessel to try to pass behind the other vessel, just as the other vessel also maneuvers to avoid a collision. Disaster strikes as you collide with the other vessel’s port quarter.
What went wrong? Here are a few rules to remember:
Rule 5 of the Convention on the International Regulations for Preventing Collisions at Sea (COLREGS) states that a vessel shall have a proper lookout at all times so as to make a full appraisal of the situation and determine risk of collision. Rule 6 states that every vessel shall always proceed at a safe speed to take proper and effective action to prevent a collision. Rule 35 outlines the sound signal requirements for restricted visibility and requires these signals to be made every two minutes when in restricted visibility.
But most importantly here is Rule 19:
(a) This Rule applies to vessels not in sight of one another when navigating in or near an area of restricted visibility.
(b) Every vessel shall proceed at a safe speed adapted to the prevailing circumstances and conditions of restricted visibility. A power-driven vessels shall have her engines ready for immediate maneuver.
(c) Every vessel shall have due regard to the prevailing circumstances and conditions of restricted visibility when complying with the Rules of Section I of this Part.
(d) A vessel which detects by radar alone the presence of another vessel shall determine if a close-quarters situation is developing and/or risk of collision exists. If so, the vessel shall take avoiding action in ample time, provided that when such action consists of an alteration of course, so far as possible the following shall be avoided:
(i) an alteration of course to port for a vessel forwards of the beam, other than for a vessel being overtaken;
(ii) an alteration of course towards a vessel abeam or abaft the beam.
(e) Except where it has been determined that a risk of collision does not exist, every vessel which hears apparently forward of her beam the fog signal of another vessel, or which cannot avoid a close-quarters situation with another vessel forwards of her beam, shall reduce her speed to the minimum at which she can be kept on her course. She shall, if necessary, take all her way off and in any event navigate with extreme caution until danger of collision is over.
What would you have done differently? What should the watch officer have done? Calling the captain to assist was a smart move, albeit a bit late in the situation. Calling the captain as soon as the conditions changed would have allowed the captain enough time to get to the bridge and assist in the watch.
How about slowing the vessel down? Reducing speed in that situation would have allowed more time to determine what was going on and many times is the only action required to avoid a close-quarter situation or collision. The other vessel may or may not maneuver in accordance with the rules — you cannot rely on them to stay out of your way. They may not see you or understand what they are looking at on the radar, or they may be distracted too.
All of us at some point will be operating in restricted visibility — it could be fog, rain, snow, sand, or mist. Understanding the actions required by the give-way and stand-on vessels is vital to maintaining a safe watch.
This article originally ran in the January 2023 issue of Dockwalk.