Boat Doc Special
A hot segment with fishing families, hybrid bay boats deliver more amenities than many hardcore bay boats. When testing several of these hybrids earlier this year, we got to thinking about the importance self-draining cockpits, especially on low-sided hul
A popular new hybrid bay-boat style serves to illustrate and define this safety and convenience feature.
FFor safety’s sake, if water comes aboard from rain, heavy spray or the almost inevitable stuffed wave, it’s important that the cockpit send it back out quickly through scuppers. And of course, the convenience and ease of owning a boat that does not rely on a bilge pump makes both keeping the boat in the water less stressful and hosing it out easier compared to a boat that solely relies on a pump to evacuate water.
So, how do boatbuilders design self-draining cockpits? Typically, the cockpit is part of the liner, the part that drops in to be fastened and/or glued onto its stringer grid and hull. The liner is watertight, so the builder can add drains in strategic places if the sole will lie above the completed boat’s waterline. To find out more about that process, Boating talked with designers from four well-regarded companies.
Veteran designer/ builder Linwood Parker of Parker Boats sets the scuppers in his new 26 Sport Hybrid crossover 3 to 4 inches above the waterline, which results in a cockpit depth of 19 to 21 inches. He adds a 1-inch crown in the deck, unnoticeable in the 9-foot-6-inchwide boat, but enough to send water to the sides. From there, it flows back to scuppers cut into in the corners of the aft cockpit, leading to hoses that run beneath the stern deck to drains in the transom covered by one-way flap valves. Both ends of the hoses are double-clamped. Stainless-steel grilles cover the drains to prevent most clogging, and both hoses are accessible through the boat’s large bilge compartment in case of a serious obstruction.
Charlie Johnson, vice president of marketing at Maverick Boat Company (an experienced former guide who also participates in product development), pointed out that cockpit volume plays a role in sizing drains, to make sure there is adequate capacity in the scupper system to free water quickly in an emergency. This consideration is especially important in the design of MBC’s
Pathfinder bay and hybrid models. Drainage is part of the company’s full CAD design process, working with weight analysis, aft hull volume, 25-inch transoms, and drain standards of the American Boat and Yacht Council. Pathfinders have raised, crowned cockpit soles with drains, covered by stainless-steel grates, recessed into the liner at the aft corners. Those drains lead through double-clamped hoses to stainless seacocks opening through the boats’ aft hull sides slightly below the waterline. Again, the drain hoses are accessible for maintenance. Several Pathfinder models have centered in-sole hatches in the cockpit, which are designed with care to fit tightly with hinges, latches and gaskets into openings with gutters around them, so water that falls on them runs to the corners and out through the drains.
Regulator Marine’s hybrid bay boats have sides that, while lower than the company’s offshore models, measure higher than those on the Parker 26SH and the Pathfinder models. Lou Codega, Regulator’s longtime naval architect, designs to rigorous ISO international standards, which require a calculation or test that shows a completely flooded cockpit will drain in a specified time, depending upon the boat’s intended
use. The designer must specify the scupper size, quantity and configuration, along with height above the waterline (5 to 6 inches), and cockpit depth. “All work together,” Codega affirms. He adds, “It’s a difficult standard to meet for a center-console, which is essentially a large bathtub.” We recently measured the cockpit depth on the company’s new 24XO hybrid at 23 to 26 inches, a comfortable level for bracing one’s lower leg against. Codega doesn’t design a crown into the cockpit sole. Instead, he adds a gradual foreand-aft slope in the sole (1-to-36 to 1-to-48) to encourage water to run aft to an athwartships
gutter at the aft cockpit’s bulkhead, where it slides to stainless scuppers recessed into the corners. From there, the drain hoses, sized to ISO standards and double-clamped at each end, run to the aft topsides at the boot tops, above the waterline, so there is no need for seacocks, and no blowback while reversing. As with the other boats discussed here, the hoses are readily accessible for any maintenance needs.
Finally, we interviewed Nick Engels, president of Crevalle Boats and himself a naval architect. Like the Regulator XO models, the family-oriented Crevalles have slightly higher sides than some other hybrids, though they are still lower than the sides on conventional center-consoles. Look carefully at the company’s 24- or 26foot models. The sole is 1 inch above the waterline. You’ll see a 72-quart cooler under the stern deck, sitting in a molded sump that is 2.5 inches deep. There’s no crown in the sole, but the edges are raised to prevent water from pooling, so it runs to the sump instead of oozing forward anywhere in the cockpit. The sump has drains in its aft corners that run through the transom. The drains are “as big as we could get ’em with stock components,” Engels explains. The company uses 1.5-inch stainless grates fitted to 18-inchlong, 1.5-inch-diameter black hose (the color discourages mold). Each hose contains a one-way valve with a spring-loaded door 4 inches beyond the grate. At the outer end, a 1.5-inch stainless through-hull just below the waterline holds a ball valve with an outer duck bill to prevent water from rushing in while reversing.
Note that each of these boat companies backs up its selfdraining cockpits with bilge pumps fitted below the cockpit soles. But the first line of defense in keeping the water where it belongs lies with those drains. It also simplifies the task of washing down. Ask about and look closely at the cockpit drainage system of any boat you are buying. —Capt. John Page Williams