GLEN JUSTICEWhen a powerboat has to speed up or alter course, it can only do so with its engines - and more throttle means more wake. GLEN JUSTICE

But the difference in draft between a powerboat and a sailboat may be less than you think. It is not uncommon for large trawlers and motoryachts to draw four feet or more – not exactly a sailboat, but enough to make depth a major factor when navigating in areas with shallow water. When you cross paths with a powerboat, don't assume her captain can ignore the sounder.

Another example, albeit less pronounced, is wind. Powerboats may not depend on the wind as sailboats do, but they are vulnerable to it. Many powerboats have tall flying bridges with lots of canvas, which can act as a sail in winds as light as 6 or 8 knots. While this is of little concern while moving at speed in open water, it can severely impact the boat while navigating a channel or docking.

Another reason powerboaters don't always yield to sailboats is that they don't understand what you are doing. Many powerboat captains do not have a background in sail, and therefore don't understand the need to tack upwind and other realities of sailing. Unfortunately, many sailors don't help this situation much, waiting to the last minute to change tacks and then coming about with a racer's flair that, though graceful and photogenic, leaves many powerboaters vexed.

To a powerboat captain with no sailing experience, you just radically changed course for no good reason. Remember that they are not watching the wind as you are, and they don't understand how it drives your boat. A better idea is to give the traffic around you the proper amount of time and space to react, and to telegraph your intentions when you can. I've had sailors look at me and point where they are going. It worked just fine.

This is also a good time to say a few words about right of way. It is true that a vessel under sail generally has the right of way and that powerboats must steer clear. But there are exceptions. If a sailboat is being propelled by an auxiliary engine, for example, it is considered another powerboat and the rules governing the meeting of two powerboats apply. There are other situations too in which sailboats must yield. The moral: don't assume you have the right of way.

GLEN JUSTICESome captains don't understand the impact their boats have on other vessels. On a wide river entrance, this boat came menacingly close to the author's trawler, for no apparent reason.Q. Why are powerboaters oblivious to the wake left by their engines?

A. This is a fair question and one I can identify with because, believe it or not, we powerboat types get jostled by wake too. True, we don't have a boom to dodge, and we probably won't be on the foredeck when the waves hit. But when a fishing boat with 1,000 HP crashes past me at 22 knots, my trawler rolls as severely as any vessel. Sailboats at least have the deep keel working in their favor. My boat can bob like a buoy if hit directly on the beam.

I believe the best way to think about this is not as a matter of power versus sail, but as a matter of sensitive versus insensitive. There are some captains on the water who just don't know – or worse, don't care – what their boat is doing to others. They don't know that sailors on deck are vulnerable and may be injured, and they don't know that they are responsible for any damage or injury caused by their wake. Their conduct is simply unsafe and unacceptable.

But there is another truth sailors should keep in mind: almost everything on the water throws off more wake than a sailboat. If your boat is powered by a small kicker or inboard, you can move unobtrusively through the blue. My boat, though slow by powerboat standards, has a 370 HP engine and I don't believe that the word "unobtrusive" was often uttered at the factory where she was born. I truly try to be sensitive to other boats, be they sailboats, powerboats, kayaks, or dinghies. But even at idle, the trawler leaves something behind it.

Q. What is the damned appeal of those large plastic boats?

A. Here, I will lean on a word often used in modern politics: tolerance. There are many boats that do not hail from your tradition or mine, but they may well be fine boats. And they may have fine captains at the helm (at least until they prove themselves otherwise).

When I walk the docks, there are many boats on the water that don't tug on my heart strings the way that a wooden ketch or a pilothouse trawler do. But they tugged on someone's heart strings. Or perhaps it was simply what they could afford. Whatever the case, there's probably a captain out there somewhere who loves her.

So when the guy in the trawler – or the spacecraft-looking jet boat – throws you a wave, go ahead and return the courtesy. He might be a former sailor.