Voyaging motorcruisers are wonderful but complex machines. Interior arrangement, hull form and main propulsion are all vital, but dozens of other critical details add up to make the difference between a safe, reliable, pleasant power voyager and one that’s difficult to handle, hard to maintain, and makes you feel less than adventurous. We’ll look here at a few of these details and at a few interesting but little-known alternatives to conventional installations. These basic but often-overlooked items are useful to keep in mind when you’re evaluating a power voyaging boat, or for future upgrades and refits on your current one.
Proper chain lockers I’m amazed at the odd and convoluted shapes some boats have for chain stowage, presumably to fit in more accommodations. Deep, vertical chain lockers are the only proper ship practice, and they are something to look for in any power cruiser.
The fact is that the only way to be absolutely sure that your chain will pay out (and stow) quickly and efficiently, without kinks or jams, is if it is stowed in a deep, vertical chain locker. This is deadly serious business. In the final analysis the only thing that stops a boat is its ground tackle. If you get in trouble and you can get an anchor down and in quickly, you’ll probably be all right.
A real-world example of this occurred on a 44-footer of my design. We were heading out for a cruise when the fuel line clogged, as we were turning among crowded finger piers. The wind was blowing pretty good, but the anchor was ready for instant deployment. I dashed forward, got it in the water, and it bit just before we were about to fetch up hard on some moored boats. This literally saved the day. Twenty minutes later we had cleared the clog and were off and steaming; no harm done.
If your chain jams in an emergency, you will be well and truly stuck. Certainly you won’t have the time to wrestle with several hundred pounds of kinked anchor and rode. Inspect the chain-locker arrangement of any boat you’re considering. A convoluted pipe-run down into a wide, flat locker is a sign of potential problems.
The anchoring bow eye Another very useful but surprisingly little-used anchoring trick is a rugged bow eye installed about a foot above the waterline at the stem. Shackled to the bow eye is a three-strand nylon chain pennant with a chain claw or shackle at the bitter end. (Or you can use a rolling hitch onto the chain instead of a chain hook.) You anchor the same way you would with any boat, but &mdash at your convenience, when everything is squared away &mdash you can go forward and clip the upper/bitter end of the pennant to the chain. Then you pay out more chain until the load is taken by the pennant, and the chain aft of the pennant is hanging slack.
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Now you’re riding on the stretchy/elastic nylon snubber, which absorbs much of the strain and shock on the anchor gear. It eliminates strain and chafe on the roller, winch and chain stopper on deck. Even better, the angle of pull is lower, effectively increasing holding power. In addition, the chain will not chafe the stem at the waterline, and if the pennant lets go, you’re still on your chain rode.
Hawsepipes with kevels Tying up to the dock is important, too. A nice feature that can be worked into many motorcruisers with high bulwarks is hawsepipes with built-in cleats. These fore-and-aft-oriented interior cleats are properly termed “kevels.” The photo below shows a well proportioned hawsehole with kevel on one of my designs. It’s arranged so you can fit your fist through it. Heavy lines with big knots pass through easily.
The really nice plus is that these cleats are not only exceptionally strong and free from chafe, but the cleats themselves are nearly flush with the inside wall of the bulwark. As such, these hawseholes and kevels don’t steal any deck space; there’s nothing on deck to trip you or stub your toes. Similarly, all the lines are largely off the deck and out of the way. The large radius edges around these hawsepipes are of solid 1-inch aluminum bar stock. This is very strong, and it is a large and smooth enough radius to minimize chafe, no matter which way the lines lead. Indeed, these kevel/hawseholes are so strong that you could lift the boat up on two of them.
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This construction works superbly with metal hulls. Similar kevel/hawsepipes can be installed in fiberglass craft, but they should be made of cast bronze or of stainless weldment. They are available off the shelf from A&B Industries, Buck-Algonquin and others.
Soft patches and access Another thing to consider on any boat is access to machinery and equipment. Once you’re smitten by the lines and arrangement of your next boat, stop for a moment to think about maintenance. Not a romantic subject but oh so important. Go back through the boat and see if there are access panels to all the principal wiring and machinery, to the tanks, the exhaust. Can you reach every seacock easily? How about the bilge? Can you get in to clean? Can you access the bilge pumps and strum boxes? How about hose clamps? Steering gear? It doesn’t make any difference how well things are built and installed. It will all either break or need maintenance eventually. If you can’t get at it, how will you maintain and fix it?
Speaking of maintenance and access, there’s a nearly invisible detail that should be built into every serious voyager &mdash a soft patch. Basically, a soft patch is a removable section of deck. Its purpose is to facilitate the removal of large components without taking a chain saw to your boat. Above, you can see the soft patch in the sun deck on one of my office’s aluminum motor cruisers during construction. But the same area after completion shows that it’s nearly invisible &mdash you could make out the lines of the edge of it if you stood on it and looked carefully.
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This patch and one in the cabin sole below permit the entire engine to be pulled straight up and out of the boat. Removing a soft patch is not like opening a hatch. In this case, it would take a day or so to clear the interior, and unbolt and remove the soft patch on deck and the one on the cabin sole. But this is for major overhauls only. Without proper soft patches you’ll be reduced to cutting and chopping out pieces of deck. Always look for and ask about soft patches when investigating a new boat.
Thoughts on steering
Now we can turn to something completely different &mdash steering. Good, responsive helm control is a must for a proper voyager. You need crisp results both at speed in rough conditions and at the dock in close-quarters maneuvering.
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Flat-plate rudders Most folks tend to think of rudders as having a standard airfoil-section shape. On the other hand, some power workboats have flat-plate rudders with external stiffeners. Neither is optimal for good steering response. And good steering response is particularly important for single-screw power voyagers.
The thistle rudder The rudder we install on most of our voyaging motorcruisers is a type we call the thistle rudder. (It was named by naval architect Frank MacLear, who was one of this rudder’s pioneers.) You can see the shape on the drawing and in the photo. The thistle rudder is smooth on the outside and has a standard airfoil section until the trailing edge, where it splays out in a sort of fishtail. In addition, you can see in the photo that there are endplates top and bottom. (The configuration will work without endplates or with an endplate on the bottom only, but the endplates make for even better steering.)
A rudder like this gives unusually positive steering response. At speed, somewhat less rudder angle is needed to get the same course correction. During low-speed maneuvering, these rudders really shine. Steering is both crisp and predictable. You can very quickly kick the stern of the boat around to exactly where you want it.
Here’s what the skipper of my office’s motorcruiser Imagine had to say about handling with our thistle rudder in just his first week with the boat:
“Imagine is doing wonderfully! To date, my strongest impression is how easily she handles in close quarters. We’ve been staying at quaint but small marinas that are quite challenging for even a twin screw to maneuver in. Two nights ago I was even forced to dock stern-to. I gave the harbormaster my length, and he asked for my beam. I replied, ’14 feet 6 inches.’ And he said, ‘Great. In that case, you can stay because I have one slip left with 16-foot width.’ And then he told me I would have to follow marina custom and dock stern-to. I had 20 people watching, and I backed in with one try &mdash without using the bow thruster. The response I got from the audience ranged from: ‘You must have been handling her several years,’ to ‘Yep, I can always tell when a boat has twin screw.’ Needless to say, I’m flattered. Imagine backs down quite straight with very little prop walk.”
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Of course Imagine is single screw. The thistle rudder doesn’t guarantee perfect boat-handling, but it does make the handling crisper, more precise and more predictable.
The Kitchen rudder There’s an even better-handling rudder that I’ve wanted to install for years. It’s the Kitchen rudder, invented by the British Adm. John G.A. Kitchen.
You can see from the illustrations and photos on the facing page (in this case of an old outboard Kitchen rudder), how the Kitchen rudder was set up. Basically, it was two half circles (somewhat conically shaped) that surrounded the prop in a ring (not unlike the Kort nozzles seen on some tugboats and trawlers). Instead of a single vertical rudder blade aft of the prop, the entire ring is rotated in unison to steer. This actually improves water flow into and out of the propeller disk, enhancing efficiency slightly.
Equipped with one of these rudders, you can slow the boat down in the usual way by cutting back on the throttle, but the Kitchen rudder offers another remarkable option. Each individual conical half circle pivots aft and together to close up behind the prop. Half closed, for instance &mdash without touching the throttle &mdash reflects about half the prop thrust forward (allowing half the wash still to flow aft), and effectively puts you instantly in neutral, even at full throttle. Fully closed, you have solid, reliable reverse. What’s more there’s no unpredictable walk to port or to starboard. In reverse mode &mdash at docking speeds &mdash the Kitchen rudder acts like a true stern thruster.
In the late 1910s or early 1920s the U.S. Navy performed trials on a 38-foot launch fitted with a Kitchen rudder. They reported that from 12 mph it could be stopped in just one boat-length. Incredibly, they also reported that the Kitchen rudder enabled this launch to be turned around on center &mdash in other words, in place! You can’t do better than that for low-speed, close-quarters maneuvering.
You wouldn’t want to put a Kitchen rudder on a high-speed boat &mdash too much appendage drag from the ring, just as with a Kort nozzle. But at voyaging-motorcruiser speed, they are ideal.
One of the great mysteries of marine design is why the Kitchen rudder has been completely forgotten. Manufactured by Kitchen’s Reversing Rudder Co. Ltd., of Liverpool, England, Kitchen’s rudder was employed extensively by the British Navy before World War II, and it won raves from all who used it. Sales and marketing here in the United States &mdash under a 1916 U.S. patent &mdash was spotty, though. The McNab Co. &mdash first of Bridgeport, Conn., and later of Yonkers, N.Y. &mdash had the American license, but though they made successful installations on everything from outboards to large ships, all traces seem to have vanished.
The hand-held helm station Returning to more common steering systems, one of the minor difficulties in handling a larger voyaging motorcruiser is that it can be difficult to see around corners or to tend lines or anchor gear from the helm. The solution is the hand-held helm.
The photos on page 46 show the portable helm made up for one of my office’s motorcruisers. Modern fly-by-wire helm controls and autopilots make such remotes possible. Basically, you pick it up and plug it in at any location on deck in which you had a helm receptacle installed. On a typical boat there might be plug-in stations at the foredeck, in the aft cockpit, and in the center of the Portuguese bridge.
The hand-held helm has a fly-by-wire single-lever throttle/clutch, an autopilot joystick and a thruster switch. Wherever you are aboard, if you can plug in this control, you can engage in any maneuver. On another of our designs, the owner likes to sit up in the bow and con the boat from there in fine weather. He gets a beautiful breeze, an unobstructed view and can stretch out with his toes over the edge of the bulwark at the bow.
Since they are electronic rather than mechanical linkages, fly-by-wire controls offer great flexibility in installation and very good helm control. They have one big drawback. What if you lose electric power? The answer is to have a backup. There are two approaches to this. Glendinning makes fly-by-wire throttle and shift controls with built-in mechanical backup at the master helm station. The other simpler and lighter approach is to install what is essentially a uninterruptible power supply for electronic fly-by-wire controls like that from the MicroCommander.
My office has used the ZF Mathers/Newmar automatic power selector, model 13505, wired to provide power from house bank and engine start battery. This will instantly shunt power from the otherwise isolated engine start battery to the MicroCommander engine controls in the event of a 12-volt-system power loss. Last I checked, these Newmar units cost only about $80 each. This is cheap insurance, and I’d install it on any serious voyager with fly-by-wire controls (or use the Glendinning or system).
Electronic diesel engines
Fully electronic diesel engines are becoming more and more common. Instead of the self-contained mechanical or electro-mechanical injection and other internal engine-control functions on traditional diesels, modern electronic diesels control these functions through one or more onboard minicomputers built into the engine package. The real driving force behind this development is environmental regulation. Electronic engines run cleaner than even the best-tuned, best-engineered, all-mechanical diesels. This is good for marine applications, too, as clean-running engines are more efficient, giving greater range. Further, the electronic package provides extraordinary electronic diagnostic output, which can’t be beat for maintenance.
There is a downside, seldom discussed, that gives me pause. A few years back, I was running sea trials on a 50-foot single-screw motorcruiser we’d just launched. The boat looked good and was running well, when there was a distant pop sound followed by a complete loss of all electric power. We found out after the fact that a chip on the microprocessor smart voltage regulator blew (it was defective) and one of the trial crew saw the DC voltage spike to over 40 volts &mdash on a 12-volt system!
This might sound bad, but it’s what sea trials are for &mdash to find and shake out the bugs. Better still, it was a superb example of how the mechanical redundancy designed into the system prevented any serious problems. The steering was manual hydraulic. The engine-start battery, alternator and regulator were isolated and unaffected, and the engine was 100 percent mechanical. As a result, we motored back to the dock under perfect control, and we even had radio and electronics as soon as we switched over to the engine start battery bank. A day later the defective chip had been replaced, and the boat was running flawlessly (and has ever since).
If this had been an electronic diesel, things could have been very different. The DC-voltage spike could have blown the engine electronics, leaving us dead in the water. There are many very fine and reliable electronic-diesel-engine boats out there. They are the wave of the future. But this aspect of electronic diesels for marine use needs careful attention. At the very least, be sure the engine start batteries and their charging system are isolated from other DC systems onboard.
Sea chests
Speaking of engine reliability, we can close by considering the sea chest raw-water intake approach. One common problem with diesels is sucking something into the raw-water intake and starving the engine and exhaust for water. Usually this is a plastic bag; occasionally it can be seaweed or kelp. The solution is a sea chest that opens on both sides of the keel with a flush grate on either side. With such a sea chest, you’d have to have a plastic bag stuck against both sides of the keel to block water flow. This is nearly impossible. What’s more, with the intake grates flush, the forward motion of the boat will sweep any obstruction off. I’ve never had such a sea chest blocked &mdash ever.
Each grate, after deducting for the mesh, must have more area than all the actual water inlets combined. Of course, the grates must be removable for maintenance. On a metal hull like this, a zinc anode would be installed in the interior of the sea chest.
Director of the Westlawn Institute of Marine Technology, Dave Gerr designs yachts and commercial vessels out of his New York City office. He is also the author of The Elements of Boat Strength, The Propeller Handbook and The Nature of Boats.
