1. A constant lookout must be maintained at all times, especially in crowded coastal waters. It’s OK to be paranoid and assume that any closing target will pass too close for safety. Never assume a large vessel will see you or maneuver to pass clear.
2. Plot the relative visual and radar bearings of all targets that are closing or remaining at a constant distance. Assume they are or will be
on a collision course until the bearing angle confirms otherwise. Recheck bearing angles frequently; just looking at radar returns is insufficient.
3. If a close approach appears likely, use any and all means to alert the other vessel of your presence. Make a voice call on VHF channel 16. If the call is not answered at once send a DSC ALL SHIPS call. (If the other vessel’s radio volume is turned down, the DSC call will sound a loud alert regardless of the volume setting.) If possible, equip the boat with an AIS receiver that will provide the Maritime Mobile Service Identity numbers of commercial vessels, enabling you to immediately establish voice contact. Have a waterproof hand-held radio with you whenever you are on deck.
4. Use a searchlight to illuminate your boat, or direct the light toward the wheelhouse of the other vessel (works in daylight, too). Use your horn. Although the type of horn carried on most yachts likely won’t be heard on the bridge of a ship, it can alert those on small vessels and anyone who might be on an exposed deck of a ship.
5. Plan an evasive maneuver that will provide the greatest distance between you and the other vessel. Execute it as soon as you are confident that doing so will not make the situation worse.
6. Don’t wear photochromic glasses after dusk.
7. Dark-adapt your eyes for at least 30 minutes before standing night watch. To preserve night vision, use red LEDs as light sources. If two people are on night watch, have one avoid exposure to light from instruments, chart plotters and radar unless they are emitting only monochromatic red (LED) light.
8. Equip your boat with one or more properly installed radar reflectors. Virtually all reflectors have significant peaks and valleys in their apparent radar cross section, so installing more than one can improve the likelihood that your boat will be seen.
9. Check your navigation lights before and during a voyage.
10. Become familiar with the hypothermia chart, and dress in accordance with the sea temperature. An immersion suit (less than $400) can save your life. An automatic inflating life raft can keep you alive, especially when sailing in non-tropical waters. Keep a ditch bag available on deck. Carry at least one properly registered 406 EPIRB or PLB.