Cockpit Drainage
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- At sea, if a boat gets pooped (a wave breaks over the stern) and the cockpit fills with water, it is of paramount important that the cockpit drains rapidly. (Cruising Handbook, p. 90)
- …it’s often possible to design in a couple of large drains at the aft end of the cockpit that lead through pipes to the transom. In addition the rapid drainage this provides, it has the advantage of putting the through-hulls just above the waterline. This is preferable to the conventional below-the-waterline arrangement, which means that when the boat is left unattended,there are at least a couple of potentially boat-sinking seacocks that have to be left open. (Cruising Handbook, p. 90)
- The Offshore Racing Council (ORC), an international body that governs offshore racing, requires large-enough drains to empty the entire cockpit – if filled to the coamings – in 3 minutes. In reality, in the kind of conditions in which the cockpit will fill, the boat will be rolling heavily; much of the water will be shed on the first roll. However, the cockpit well is likely to remain filled; therefore substantial drains are still needed If the well takes event a minute to drain, it will seem like a very long time the larger the drains, the better (again with some type of screen). (Cruising Handbook, p. 91)
- …a cockpit may be too big…the cockpit may be filled or partially filled with so much water that the boat’s stability and buoyancy are threatened….regardless of the volume of the cockpit, the drains should be large enough to drain it completely in three minutes after it is filled to the combing. The ORC specifies four drains totaling 1.77 square inches of area, but I canrecommend two 1 ½” drains, which have an area of 1.77 each….we use a single 4-inch-diameter drain…giving an area of 12.57 square inches (Desirable and Undesirable Characteristics of Offshore Yachts, p. 122)
- A boat at sea can and more than likely will be pooped sooner or later…Carl Alberg, designer of the Triton, calculated that a flooded cockpit would lower the stern just six inches….From one point of view, a cockpit can never be too small. But comfort is its own dictum. (Upgrading the Cruising Sailboat, p. 177)
- The Offshore Racing Council limits cockpit volume to 6% LOA x max beam x freeboard aft. (Upgrading the Cruising Sailboat, p. 176)
- Cockpits frequently accumulate puddles in the most aggravating places….resulting in permanently wet backsides and feet. (Cruising Handbook, p. 92)
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