Maritimo C47By Capt. Richard Thiel
More Than Meets The Eye
Sometimes it’s not just about the boat
You probably assume that the most interesting part of a boat test is evaluating how she performs. Or maybe observing how accommodations and living spaces are arranged and fitted out. But every now and again I come across a boat that’s about more than these things, a boat with a backstory just as interesting—and in some ways more telling—as how she looks and runs. That was the case when I went to Gold Coast, Australia, in May to test the C47, Maritimo’s first pod-drive boat.
The backstory began with a tour of Maritimo’s four boatbuilding sites. Now I’ve toured a lot of boat factories and seen plenty of fine facilities, some with shops dedicated to things like paint, upholstery, wood, and metal work. But on this tour I saw something I’d never seen at any boatbuilder: a foundry (see “Noteworthy,” this story). And the Maritimo machine shop next door was nearly as impressive. Not content to purchase shafts from an outside supplier, Maritimo buys stainless steel stock and machines it into tapered and keyed propshafts. Talk about vertical integration.
Later that day the backstory continued to unfold during an hour-long interview with Maritimo founder and CEO Bill Barry-Cotter, a guy who knows not just the business of boats but the design and construction of them, too. Our conversation quickly segued from the business and marketing topics to the minutiae of hull design. I was particularly curious why it had taken Maritimo so long to build a pod-drive boat, especially when Barry-Cotter had publically stated his skepticism, especially in light of alternative systems that offer integrated joystick control of straight-inboard drives and bow and stern thrusters. Why the change of heart, I asked. “Quite simply, I listened to the marketplace,” he explained. And seeing the demand, he committed to approaching his inaugural installation from a different angle. One focus was something that obsesses Barry-Cotter in both his production and race boats: weights and balances. Aware that pod drives place more mass farther aft than comparable straight inboards, he says he worked with Volvo Penta to develop a hull with a relatively flat running surface and wide chine flats aft that together create compensatory lift. He also removed “rocker,” that fore-to-aft curvature (think of a banana) that helps a boat get onto a plane, aiming to avoid the bow-high running angles that characterize many pod-drive boats—especially during planing—and exaggerated heel in high-speed turns due to the drives’ being canted outward.
The other angle was also born out of racing: safety. When I suggested that IPS had created a lot more interior volume on the C47, he demurred, saying utilizing the entire bonus area forward of the aft-mounted engines would have precluded his requirement that the boat have four watertight compartments, any one of which could flood without sinking her. He contends that the midcabin directly forward of a pod engine room bulkhead is often so large that were it alone to flood, it could sink the boat. Additionally, he explained that pod engines and drives concentrate so much weight aft that if just the engine compartment were to flood, the boat would go down by the stern. To preclude this, the C47 has a smaller midcabin than a typical comparably sized pod-drive boat and a sealed “buoyancy chamber” (see photo, page 83) outboard of each engine, the first boat ever to employ such a feature.
Out on the water the next day, my first impression was of the C47’s solid feel, which I attribute to the four fully glassed-in bulkheads that act as ring frames. My next one was that she is a fine performer, an impression supported by our data: a top speed of nearly 31 mph, but more important, an efficiency of 0.81 mpg between 10.8 and 17.2 mph and a fast cruise of 23.8 mph (3000 rpm) at just a tick less than that: 0.78 mpg. And even with a modest fuel tankage of 476 gallons, she still enjoys a range well in excess of 300 miles all the way to WOT.
Two more things stood out. One, trim angles peaked at 5.5 degrees at 3000 rpm, then flattened to 5.0 at WOT. But with a bit of tab, I could keep her on plane at around 3.5 degrees all the way down to 1500 rpm, where I squeezed out nearly 1.5 mpg out of this 36,400-pounder. Two, the C47 is quiet. While peaking at 78 dB-A, a 2500-rpm cruising speed (17.2 mph) saw 71 dB-A, just a bit above 65 dB-A, the level of normal conversation. (Production boats will get even more engine-room insulation.)
At WOT, the C47 heeled only moderately in even aggressive turns and without the disconcerting loss of visibility I’ve experienced on other pod boats. Her turning radius of about three boat lengths and responsiveness to wheel input at all speeds supports Barry-Cotter’s claim that this installation utilizes 100 percent of the available IPS steering range, the first such boat to do so, he says.
As for the layout, it was a work in progress when I saw it. Although the final design will be largely what you see here, there will be changes that resulted from extensive dealer input—again, Barry-Cotter listening to the marketplace. LOA will not change, but the transom will move aft by about 14", increasing the size of the cockpit and the engine-access hatch in its sole. Inside, the galley will be L-shape and the port-side saloon sofa will be shortened by about two feet to accommodate a wider stainless steel sliding door that will provide easier access from the cockpit.
IPS means the engines and drives are directly beneath the C47’s garage, which might compromise their accessibility without those changes to the transom-cockpit area. Above the garage, a seven-foot-wide transom console is flanked by stairs to a swim platform that will grow from three feet deep to better than five feet, with an additional hydraulic platform an option. That console contains a standard sink and fridge/freezer and can be ordered with an electric barbecue, making the cockpit a great place to entertain, even though there’s no built-in seating.
And what of that space that didn’t go to the midcabin? It’s a two-level lazarette accessed via that soon-to-be-bigger hatch in the cockpit sole and provides a home for sea strainers, batteries, the standard 11-kW Onan genset with soundshield, and enough space to stow miscellany like fenders and lines. There would be more stowage but for a 4'x2' protrusion on the forward bulkhead, which, it turns out, makes space for a nice double hanging locker in the midcabin. That midcabin certainly felt roomy, an impression enhanced by large port and starboard windows. Indeed, it’s a toss-up as to which of the two cabins I’d prefer. The midcabin is bigger and has more stowage—production boats will get a chest of drawers at the foot of the starboard love seat—but the forward cabin is nearly the same size and has an overhead hatch and a more airy feel. Both have en suite heads with enclosed showers and hatches.
The backstory of the C47 really is nearly as interesting as her numbers and accoutrements—but not quite. After all, nothing is more rewarding than running a good-looking boat with sparkling performance, and C47 is definitely that.
Maritimo USA (206) 462-6080.
This article originally appeared in the August 2010 issue of Power & Motoryacht magazine.