If you’re just passing another boat in open water, it’s probably not a big deal. Cross his stern as early as possible, leave plenty of room, and be mindful of your own wake. But if you’re both headed the same direction along any type of defined channel where there is limited room to maneuver, passing another boat is similar to what happens to cars on the road. There are a few differences. And there are rules.
First, and here’s a big difference, you don’t automatically have the right to pass another boat. A boat planning to overtake (pass) is called the “burdened” or “give way” vessel, while the guy up front is considered the “privileged” or “stand on” vessel — he has the right of way. Before passing, the burdened vessel should ask — and receive — permission from the boat up ahead. The privileged boat has the right to deny the burdened vessel the right to pass. Maybe it’s because of oncoming traffic, a narrow channel that doesn’t leave room for the privileged vessel to maneuver, or a concern that your wake could cause damage to the privileged vessel’s cargo or crew.
Recreational vessels should indicate their intentions to another using their horns. 2 Short Blasts: “I intend to pass you on your port side.” The privileged vessel will signal agreement by responding with 2 short blasts. 1 Short Blast: “I intend to pass you on your starboard side.” The privileged vessel will signal agreement by responding with 1 short blast.
When it’s one pleasure boat passing another pleasure boat of similar size, the passing rules are not always observed, but they should be. At a minimum, there are some common courtesies that should be observed.
When overtaking another boat, your goal should be passing with the smallest possible wake. When passing in a controlled speed or no-wake zone, extra caution will be needed to prevent throwing a big wake that could dislodge dishes or topple passengers. At higher speeds, judgment needs to come into play. Sometimes slowing down might actually produce a larger wake and prolong the damaging wake. Staying on plane and giving a bit more room might produce much less wake. Also, keep in mind that slowing at the wrong time can plow up an especially large wake as your boat settles off plane.
Experienced skippers will often work together when passing in slow-speed zones. In such cases, the overtaking boat will wait until the boat being overtaken slows to almost idle speed and moves as far to the right of the channel as is safe and practical. This will allow the overtaking boat to pass while still maintaining a proper no-wake speed, and will keep everyone on a friendly, even keel.