The Enduro 54 being an aluminum exploration sailboat programmed to cross the world's most challenging seas, her design process includes great attention to details to make her truly seaworthy and secure. Better to plan for the worst or the unthinkable that will never happen, rather than being sorry.
Aluminum hull with reinforced structure, watertight compartments and hatchways
A sturdy build for a "belt-and-braces" expedition vessel ! An exploration sailboat designed to navigate in some uncharted areas and in high latitudes where ice may be present, must have a hull and structure with appropriate scantlings, not to mention the possible collisions with UFOs i.e. floating objects such as submerged containers, wooden logs, ...on any sea. Lifting appendages, a swing centerboard and pivoting rudders considerably reduce the risk of major damages. The front parts of the hull, the rear bottom and the grounding sole under the central skeg (hull bustle) are made of thick aluminum plates (16 mm for the latter). The structure includes not only a reinforced bow, but also a girder (keelson) over the entire length of the hull on either side of the centerboard trunk. Overweight that does not penalize performance and contributes to the vessel stability, due to its low position. This sailboat can access more protected moorings, even shoals thanks to its shallow draft, or easily dry out at low tide. A forefoot towing chainplate allows the boat to be pulled over dry land with a tractor.
Moreover in heavy weather the boat must be suited to become totally waterproof, when necessary. Not only all the portholes, deck hatches with ventilators, dorades, but the companionway indeed must be designed to close hermetically swiftly. A true watertight single door easily closed or open allows entry into the pilot-house and can be kept in the open position without intrusion in the cockpit. Very different from the inconvenient typical companionway washboards, lengthy to close, often not really waterproof, or even with louvers. This door also provides a welcome security when cruising abroad, in some countries with unsafe marinas or moorings, exposed to various types of theft ...
Watertight bulkheads and doors
In addition to the pilothouse bulkhead and bulletproof door, this sailboat incorporates 3 watertight fore and aft bulkheads with waterproof doors or hatches. The boat is thus separated into four, in fact five when counting the bow-thruster trunk, watertight compartments with their own bilge pump. A first watertight compartment just behind the bow is accessible from the forepeak through an aluminum hatch and a collision bulkhead. Then comes the watertight bow thruster locker up to half height and the large walk-in forepeak in front of the heated interior part of the boat, separated by a structural aluminum bulkhead and an another watertight door. Aft, the cabins are separated from the lazarette and cockpit lockers by a third watertight bulkhead including an escape hatch in each cabin. Thus, in the event of a potential water ingress, it is possible to confine it to one of these compartments. The central compartment is equipped with an automatic high flow bilge pump. The rudders are independent of the hull; in the event of a damaged bearing or rudder ring, no water entry is possible into the boat, even in the aft lazarette. The rudders can be removed without hauling the boat out and again without any possible leak.
Moreover the number and location of the through-hulls fittings for seawater intakes or discharges have been optimized and all the valves are mounted on aluminum tubes welded to the hull rising above the waterline.
Crew inside the cockpit are protected by the coachroof cuddy, also the two outer helm stations are not directly against the transom at the mercy of a bad wave. It is possible to steer the boat from inside the pilothouse. Elevated stanchions (820mm), lifelines, handrails, numerous anchor points for harnesses, granny bars (mast pulpits) and a long aft pushpit protect the crew. In the event of a man overboard, the transom platform and aft gantry make it easier to get a crew back on board becoming quite heavy with the boots and weather gear flooded with water.
On board fire fighting
The greatest danger on board a yacht is not a water ingress, but a fire. You often have hours to stop water entering the boat, or in the worst case have time to leave the boat. In the event of a fire on board, minutes can mean the difference between life and death. Toxic smoke is immediately produced and quickly spreading throughout the ship. Good fire protection as well as several emergency exits at different boat ends, so as not to remain trapped into a cabin, are critical.
Automotive grade materials are used to insulate the boat with fire resistant foams and electrical cables. Different types of powder or foam extinguishers are distributed on board, behind the stove at the front of the saloon, in the steps of the companionway and the aft port cabins, in the forepeak near the workbench; in addition a multipurpose powder fire extinguisher is available outside the boat in a watertight cockpit locker close to the helm stations, an automatic fire extinguisher / fire suppression system (e.g. HFC 227) for the engine room and a Nomex blanket for the galley, most effective to cover and stop a frying oil fire. A propane gas detector under the gas cooker and several fire alarms are positioned across the boat (peaks and cabins).
Whether in the event of a fire or a rollover when capsizing, several emergency exits have been included in the boat. It is possible to escape, in addition to the companionway door and deck hatches, for example in the event of toxic fumes inside the main central part of the boat, through the forepeak deck hatch or at the stern through escape hatches inside the aft cabins bulkhead and the cockpit floor.
Large aluminum deck hatch for the forepeak, used to take out the sails : gennaker, spinnaker, or sporting leisure or expedition gear when at anchor
Watertight hatches in the aft cabins providing access to the stern compartments
Emergency exit into the cockpit from the 2 aft cabins
In the event of capsizing by a rogue wave and a rollover, less likely with a centerboarder (see keel broach effect), the boat should not remain upside down for very long. Since most of the ballast is positioned inside the skeg (hull bustle), there is no risk of losing stability, contrary to a vertical lifting keel sailboat where the ballast concentrated into a torpedo bulb suspended at the bottom of the keel is particularly vulnerable, subsequent to a bad collision with a submerged container or a rock. In addition the volume of the superstructures tends to decrease the inverted stability; in particular the shape of this watertight pilothouse contributes to making the boat more unstable upside down too.
Let's assume a really extreme case where the rigging still in place, at least partially, with all the sails in the water, drags and manages to keep the sailboat upside down. If you need to get out, for example to free the rigging or the sails, it is obviously not possible to open the deck hatches or the pilothouse door without risking condemning the boat to sink. A hatch on the cockpit floor, just next to the life raft locker, with access from the aft cabins, being clearly above the water surface (simple hydro simulation upside down), it is possible to open it and exit without risking flooding the stern peak and even less the rest of the ship, assuming the aft cabins hatches have been closed after going through.