Some folks distrust technology and want to stick with mechanical devices that are easy to maintain and repair. Almost anyone can figure out paravanes, the cruising powerboat’s traditional means of reducing and even stopping roll. If you’re a Luddite but you want to cruise offshore in comfort, maybe they’re the solution for you.
Paravanes, sometimes inaccurately called “flopper-stoppers,” are Rube Goldberg arrangements of booms, wires, winches, chains, and ropes towing delta-shaped metal “fish” whose drag helps resist rolling. Rigged to port and starboard, in use the booms (each one typically longer than the boat’s beam) are lowered nearly to horizontal, giving a yacht the look of an offshore commercial fishing boat. Paravanes are relatively inexpensive, simple, reliable, and effective; they were the norm among long-distance powerboat cruisers until a couple of decades ago, and some hard-core cruisers still use them.
If the gear is properly designed, deploying the booms and handling the fish are relatively easy with practice, especially on smaller boats. Most passagemakers launch the fish when leaving port and pick them up on the other side of the ocean; they don’t use them for short runs, so handling is minimal.
So what’s the catch? Few people will hassle with paravanes for an afternoon’s ’longshore cruise. In larger yachts paravanes become unwieldy. The booms and fish are heavy and have to be deployed carefully; the controlling gear has to be of top-notch quality and expertly arranged to allow safe handling. If a fish or a boom gets out of control, something’s likely to break.
Also, towing the fish costs speed and cruising range thanks to drag; long-distance powerboat cruising tends to takes place at low speed to start with, so you don’t want to lose anything. At some point you’ll be better off in a sailboat, which is naturally stabilized by wind pressure on the sails. Active fin stabilizers create almost no drag.
While some long-range cruisers still use paravanes, most serious cruising folks today rely on mechanical or gyro stabilizers. They are more effective and reliable than the Luddites would have you believe.