Off-center, it functions just the same in the engineering spaces as elsewhere,” with the caveat that it must be securely mounted to the strong elements of the hull structure, such as engine stringers or similar heavy timbers in the vessel’s hull, something of particular importance in wooden boats and certainly in older hulls. Todd emphasizes that the gyro does not need to be mounted over the centerline: “It can be mounted belowdecks wherever you have room. The gyro is internal, and as such there is nothing attached to or poking through the hull.” “There is no drag or risk of snags, and this also means that we don’t have to compromise the appearance of these classic hulls. One major advantage to having a stabilizer installed, Todd says, is the lack of any traditional external fins or appendages. He restores classic wooden power cruisers, many of which, due to their antique vintage design, have round bilges which facilitate rolling, and generally high decks the higher you are off the water, the more pronounced the effects of rolling will be to passengers. I spoke to Todd Jarem at McMillen Yachts, Inc. Only the smaller gyro systems can be run off of the house batteries and 12V alternator. Powerboats in the 30- to 60-foot range typically need generators to power their gyros, generators that are powered up the entire time the motorboat is at sea, and the voltage demands also vary, with larger gyro installations requiring 240VAC. Gyro systems are also best suited for powerboats because they require a good deal of electrical power to operate, something certainly not readily or constantly available on a sailboat. The gyro on "Miss Asia." Photo by Greg Jarem, McMillen Yachts, Inc. But the ride will be more comfortable and the boat easier to handle when the sea state becomes moderately choppy. And while a gyro stabilizer may stabilize a powerboat’s motion and make it feel more seaworthy in rough water, having a gyro stabilizer will not make your powerboat appreciably more seaworthy than it actually is, and certainly not more stable (or even as stable) as a keelboat, so one should not be misled. And, as we are taught in Boating 101, sailboats with keels are inherently more stable than powerboats, period. A few thousand pounds of lead hanging from the keel are all the stabilization necessary for them. Other than a cathedral hull or multihull design, just about any monohull powerboat will benefit from the effects of a gyro stabilizer. Although the dampening effect of a gyro on rolling is especially appreciated on older-design boats with a round bilge, plenty of hard-chine hulls respond favorably to the effects of a gyro since they, too, can become particularly uncomfortable underway or sitting stationary in a cross or quartering sea. The shape of the powerboat’s hull doesn’t matter all that much. Stoutly fastened to a vessel’s structural frame, the gyro in operation steadies the vessel in choppy waters to lessen the effects of wave action, particularly in a beam sea, and ranging from light chop to rougher sea states. The heart of the system is a spinning flywheel mounted in a gimbal frame that allows it two of the three possible rotational degrees of freedom. Even a powerboat with a poorly riding design can swim more sweetly over the waves with a gyro stabilizer. Simply explained, marine gyrostabilizers reduce the rolling motion of boats and ships in seas, giving traditional as well as modern hull designs better comfort and stability than these hulls innately possess. Pictured is the yacht "Miss Asia." Photo by Greg Jarem, McMillen Yachts, Inc. Manufacturers claim that these gyro stabilization systems eliminate up to 95 percent of boat roll. We’ve all been familiar with such systems used in cruise ships and larger vessels, but for more than a decade now they have been available for the small-boat powerboater with a craft even as small as 23 feet LOA. One of the greatest innovations to come along in recent years has been the development of gyro stabilization systems in sizes and configurations adaptable to installation in smaller craft.