Collision Avoidance 101

Mike Baron, U.S. Coast Guard, Boating Safety Division

The Coast Guard Station got the call at 3 p.m. on a clear day in January. Two powerboats had collided and were pinned together. Three people from one vessel had been injured and were quickly transferred to local emergency medical services. Fortunately, there were no fatalities. Collisions involving recreational boats are a dangerous and all-too-frequent mishap on the water. In an average year, more than 1,300 injuries and 120 deaths result from boats colliding with other vessels or fixed objects, with people often thrown overboard by the force of the impact.

Navigation Rules help prevent collisions by establishing prescribed maneuvers and signals when two vessels cross paths, are on course to meet head-on or when one vessel wants to overtake another, along with rules for operating under restricted visibility and requirements for navigation lights and sound signals. It is every boater’s responsibility to know the rules, yet we still see operator inattention, operation at an unsafe speed and failure to post a proper lookout contributing to collisions on the water.

If you find yourself in imminent danger of a collision, you may depart from the rules and take whatever actions are necessary to avoid it. Altering course may be the most effective action, if done quickly and if the action doesn’t put you in close quarters with another vessel. Depending on the situation, slowing, stopping or reversing propulsion may be appropriate. But whatever the course or speed changes, they should be substantial enough to be readily apparent to the other vessel, so the other boater can avoid taking actions that cancel out your own.

Here are more tips.
1. Maintain a proper lookout. This is a rule too often ignored by boaters, especially in calm, clear weather. Stay alert to on-the-water traffic in every direction, including the stern, and keep noise distractions to a minimum. At night, you may have difficulty spotting an approaching vessel, even if the weather is clear. Other vessels may appear as black shadows moving across the water or against a background of shore lights. Keep binoculars on hand to help you determine a vessel’s speed and direction of travel. If you see only one sidelight, you can be reasonably sure you’re not in the ship’s path. If you see both sidelights and a white masthead light, it’s coming right at you.

2. Operate at a safe speed. Make sure your speed and distance from other boats give you ample time and space to avoid a collision. Some states have established a safe operating speed and minimum distance whenever boaters are operating above a no-wake speed. But what constitutes a “safe” speed will vary depending on weather and water conditions, proximity to navigational hazards, the amount of surrounding boat traffic, and the stopping distance and maneuverability of your boat. When visibility is restricted, navigate with extreme caution.

3. Watch out for the big boys. Wherever large ships and recreational boats operate, there’s a risk of collision. If you navigate in or near commercial ports, remember that large ships have to stay in the deep channels and have limited maneuverability. Try to avoid operating in ship channels, especially at night or during periods of limited visibility. Do not underestimate the speed of a large vessel, and stay alert to its position. Ships following a winding channel may appear to be heading away from you one minute and bearing down on you the next.

4. If you must cross a commercial channel, cross astern of a ship at a right angle to traffic, and make sure you have enough wind or power to get safely across before another ship approaches. Also, watch your position when a ship is passing nearby. Large military and commercial vessels displace many thousands of tons of water. Operating at normal maneuvering speed (10 to 15 knots), they can generate sizable waves as their wake passes from deep water to suddenly shallow water, slamming a small boat against jetties, rocks, bridge structures and other fixed objects.

5. Make sure other boats can see you, especially at night. In periods of limited visibility, large ships may be operating solely on radar, so a radar reflector mounted high on the boat is a must. At night near shore, your navigation lights may blend in with background lights. If you see a vessel approaching, don’t assume the other vessel has seen you. Make sure you follow the rules of the road, that your navigation lights are energized and burning brightly, and have a plan ready if you need to take evasive action.

6. Know how to use your radio. If you have a VHF-FM marine radio aboard, Channel 13 is the frequency used to arrange meetings and passings between ships and other vessels. They will not be focused on small recreational boats. It is your responsibility to stay out of the way.

7. Anchor in a safe spot. It is dangerous and illegal for boats to anchor in navigational channels or tie up to marker buoys. Carry up-to-date navigational charts of your area to determine where the channels are located. Paper charts are available from many commercial providers as well as from the U.S. government. You can also find print-on-demand versions online. In large, open bays, the channel is not always clearly defined. A chart can tell you where the boundaries are.

8. Understand sound signals. Horns, whistles, bells and gongs are used during periods of restricted visibility and when vessels are in sight of one another. Five or more short blasts is the “danger” signal. If it’s meant for you, you must take fast and positive action to avoid a collision, and that action must be obvious to the other vessel to avoid any confusion.

9. Stay sober. Nearly one in five boat-accident fatalities each year is a direct result of boat operators and/or passengers being “under the influence.” Skillful, responsible seamanship requires a clear head.


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