Rule 7 of the Navigation Rules says that you “shall use all available means appropriate to the prevailing circumstances and conditions to determine if risk of collision exists.” If there’s any doubt, assume that there IS risk of collision, and take the appropriate action as required under the Navigation Rules. Take systematic collision bearings on the other vessel; if the bearing doesn’t change over time, risk may exist. It’s sometimes difficult to judge the potential for collision when one or both vessels are moving quickly, when you approach a large vessel or a tow, or when you are close to the other vessel. AIS and/or radar can help, but also use your eyes. For the text of Rule 7 see www.navcen.uscg.gov/?pageName=navRulesContent.
Priscilla Travis spends more than 110 days each year on the water, takes photos, and writes about nautical topics.