For those who are technically minded, we have included this page which we have unashamedly poached from another website. It’s primarily Bill Lee’s write-up about the boat, with some changes and additions which reflect ongoing projects and upgrading. It’s worth skimming through just to get some idea about the engineering which went into Rocket Science.
Model: Riptide 55 Designer: Paul Bieker. Built at Shaw boats in Aberdeen, WA. Finishing and commissioning were done at Seaview West and CSR in Seattle.
Construction: Carbon fiber/glass/duracore balsa /nomex composite
The RipTide 55 is designed to be the next generation of club racing and long distance cruising yacht. Rather than a highly specialized cruising yacht like the Sun Deer or Deer Foot series, the emphasis is on an all around boat that can be used for club racing and coastal cruising but is also engineered and capable of long ocean passages. This is the same concept that Nautor and Baltic have used for years that has preserved the value of their boats over a sustained period of time. However unlike Nautor and Baltic who have not updated their use of materials or available technologies, the Riptide 55 incorporates very high-tech materials and proven design concepts that have proved themselves over the years at the highest level of offshore ocean racing. Extensive use of carbon fiber, kevlar and honeycomb cores has produced a boat with ultralight displacement ratios and with the strength and integrity that is far in excess of even the stoutest cruising boats. From the comments below you will see how using these materials to lower the center of gravity has produced a very light boat that has an extremely seakindly motion and very little tendency to pound. Pounding when going to windward has been the Achilles heel of the last generation of light weight cruising boats. Some manufactures have even tried to side step this problem by installing large engines and focus on the virtues of motoring to windward.
Design and Engineering Process
The RipTide 55 used a paperless designand engineering process. The design, drawing and engineering process was integrated into one process and was all done on the computer. It is not uncommon in today’s design world to have one person draw the lines by hand then turn their work over to another person who then adds the interior, another person then takes those drawings and inputs them into the computer after all this is done the plans are then turned over to a structural engineer who often takes a “cookbook” approach to figuring out panel, stringer and laminate scantlings. The designer, Paul Bieker, did all the CAD work, finite element analysis and engineering. Paul is known for his engineering expertise in structural trouble shooting on large ships and yachts. Paul is also known for producing this country’s fastest International 14 Designs and Paul has logged over 50,000 offshore miles cruising. Paul is one of the few designers that has the ability to integrate the engineering and design process all in a paperless computer design that truly has everything meeting in three dimensions. This process is often used on the large commercial ships but is rarely seen in the world of yacht design. In addition Paul is on the leading edge of monohull development by his dedication to the International 14 class which has pioneered most of today’s speed innovations such as articulating bowsprits, flexible rigs, and large roached mainsails. Paul also is part of the design team for the BMW/Oracle team, with the latest example of his work being the design of the lifting foils for the AC72 catamaran being used in the America’s cup defense. Paul’s intuitive design insights and fundamental understanding of today’s modern materials has produced a truly unique yacht which is not available anywhere else and the concepts of which could not be easily reproduced without the subtle knowledge of how these materials were used.
In order to be a truly seaworthy yacht the Riptide 55 had to be able to endure years of ocean abuse and be able to sustain hull integrity in the case of hitting a log or container at 14 knots or hitting a rock with the keel at 12 plus knots. In order to accomplish these requirements true base line engineering was used that combined finite element analysis along with a panel testing program that field tested the computer assumptions. What was apparent from the polar predictions was the extreme speeds that a yacht like the Riptide 55 can generate. For this reason it was decided not to use the ABS guidelines for yachts, those standards did not adequately address the speed potential of today’s modern craft. Instead the standards selected were ABS slamming standards for high speed military craft and Det Norske Veritas standards for high speed offshore motor craft. Using these standards a loading of 7.5 PSI was arrived at, approximately double ABS standards. To put this number into perspective, the RT55 could slam on an area of a little over a square meter in front of the keel for the life of the boat. These are extreme conditions found when flying off of waves in the worst conditions. In order to keep the panel from flexing and to provide fatigue resistance the panel specification was set at 40 PSI so that the maximum loading was not to exceed 20% of the panels specified breaking strength. A laminate schedule was modeled in the computer and then panels were made by the builder and tested by Gugeon Brothers to see if they met the specifications. The panel for the hull bottom has a core of 1″ Baltec Duracore and skins of carbon fiber and unidirectional glass. Upon testing of these panels a breaking strength of 54 PSI was found, well in excess of the 40 PSI specification and a number realized only in high speed power craft. Even more important in a panel test of 400,000 flexing cycles of 25 PSI ( half the panels breaking strength and over three times the required extreme specification) no softening was found. This is unprecedented. The next time a manufacturer makes claims about their hull’s strength ask to see the documentation for the underlying engineering assumptions, the finite element analysis and the panel testing data to back up the assumptions in the finite element analysis. The question becomes why make the panel so strong. The answer is that the panel had not only to sustain the slamming conditions at sea but with all the debris in the modern ocean it had to be able to sustain a collision with a solid object such as a log or a cargo container that had been lost off of a deck of a ship. Keep in mind that the RT55 is capable of speeds over 20 knots. The deceleration from such a hit would be dangerous enough without having to worry if the boat would disintegrate. As further protection from such a catastrophic situation a kevlar crash barrier laminate was added in the center 30 inches of the hull forward of the keel. This laminate is next to the core on both sides underneath the carbon fiber. This is counter to present conventional thinking which would put the kevlar on the outer laminate because of its abrasion resistance. What was found in the panel testing at Guegon was that the kevlar in a catasrophic hit would shatter on the outside skin because of its brittleness and the stiffness of the underlying core and laminates and even potentially holed. Dropping heavy metal balls on the laminate it was found that while the glass and carbon skins were breached that the laminate hung together because the kevlar as the last line of defense works in tension to absorb the energy of the of the object and while delamination occurred the laminate was not breached. As a belt and suspenders approach to hull integrity, integral sewage, fuel and water tanks form a double bottom in the critical areas of the boat in case of a grounding on a beach or a reef. The RT55 also has forward and aft semi water tight compartments to increase survivability in the case of a collision.
While there was much attention to the hull and its integrity, the decks had many requirements put on them. They had to sustain heavy seas and provide a stiff lid to the whole boat. The deck panels on the RT55 are carbon fiber skins over a honeycomb HRT type core and then a 4 oz. layer of glass is put over the carbon fiber for fairing purposes and to add resistance to denting from dropping tools or winch handles on the deck. The breaking strength of these panels were over 34 PSI and more importantly when fatigue cycled no appreciable softening was found. Also upon failure of the panel there was a core failure not a skin delamination as is often common in a honeycomb panel. How did this happen? The lay up of the deck panels was done out of high tech materials in a fairly low tech way. The panels were laid up flat on a vacuum table. Compared to some panels they are relatively resin rich, particularly compared to those panels that use prepegs. What this extra resin did was to wick it self up a portion of the honeycomb section and form a “miniscus” that would lock the core in place to the skin. Also because the panel was laid up flat on a vacuum table and not wrapped in place the “miniscus” was very even throughout and not pooled up on one side if laid up on a curved surface. That is why prepegs are often used is to prevent the pooling of resin in the honeycomb cell. While the panels might weigh more ( 1 lb. per sq. ft. versus .8 lbs. per sq. ft. for a prepeg panel) fatigue resistance and strength comparable to a much heavier balsa core panel was achieved for a very small incremental gain in weight.
Hull Shape and Stability
When viewing the profile of the hull plan you will notice that the deepest portion of the hull is forward of the keel area and that the hull is very deep below the waterline for its displacement. Because of the deep section forward the run aft is very long. When viewed in section you will see a very narrow waterline beam with the hull flaring to provide reserve buoyancy. The front portion of the boat has a very narrow and deep “V” section almost to the keel. This is why the boat pounds much less than other ultralight boats. Again this is counter to the present thinking that light boats had to have “U” shaped or canoe shaped sections in order to have any stability. This is where the investment in the carbon fiber and nomex pays off. The stability of the boat is achieved through a low center of gravity not the hull sections. A boat with “V” sections would roll excessively if it used balsa or foam core decks. By keeping the deck weight and the bulkhead weight in the 1 lb. per sq. ft. range the center of gravity is lowered radically compared to what are considered the high tech production boats on the market. The deep “V” section also provides compounding benefits on weight distribution and interior accommodations. By having the round deep sections in the hull, the integral tanks all are below the water line. This puts the top of the fuel and water tanks almost a foot below the water line. A full load of fuel and water of approximately 2000 lbs. now adds to stability. In most ultralights the fuel and water tanks wind up in the settee area
above the waterline because of the “U” shaped sections or even worse yet in the ends of the boat. In the RT55 the salon sections in the center of the boat are now available for extensive provisioning and the load is averaged right at the waterline. Adding fuel, water and provisions will actually increase stability like on a heavy displacement boat not decrease it like on most ultralights. The only reason a heavy displacement boat increases stability when it is loaded is because the bilges are so far below the waterline. However anyone who has had to go “locker diving” on their bellies into the bottom of a locker on a Swan to get a beer will appreciate the interior storage arrangements in the RT55. Even better yet all of the provisions, fuel and water are kept in the center of the boat which will greatly decrease the pitching moment. By being able to use the fuel and water tanks as the cabin sole the occupants are raised and can look out the windows in a light and airy interior. The benefits of the deep “V” sections allowed the designer to draw a hull shape that is almost even through out its range of heel. Most ultralights will go bow down because of the broad sterns and “U” shaped sections. The deep “V” section also greatly lowers the wetted surface and wave making resistance. The deep narrow section up front greatly disperses the pressure of the bow wave. The validity of this concept has been proven in the International 14 fleet and also in the America’s Cup where the winning New Zealand boat had very fine deep sections forward. Also the positive range of stability at 137 degrees again is unprecedented on a boat whose D/L is under 70, another benefit of the deep “V” sections forward. By using modern materials to radically lower the center of gravity we now have an ultralight yacht with load carrying ability and sea keeping characteristic of a much heavier yacht.
Again nonconventional thinking was applied to make the rig easy to handle, and to supply a great deal of power. The rig is a carbon fiber model manufactured by Hall spars in 2006. The swept back spreaders allow for a very stable platform and a mix of rod and Kevlar rigging keep the weight aloft low while still maintaining reliability. The large roached mainsail provides a great deal of sail area for the fractional rig with a height of only 65′ 5″ off of the water line. The bowsprit allows an asymmetrical of over 2200 sq. ft. to be flown and the RT55 to carry a downwind sail area in excess of 3000 sq. ft. The purpose of the rig was to keep the weight as low as possible and to keep the center of effort of the sails as low as possible. The sail with its large roach also has a small gaff at the head. This provides an “Automatic Transmission” effect. The flexing off of the head also instantly lowers the center of effort of the sail. When looking at the mast you will see that it is mounted on a tabernacle on the cabin top and that the boom is mounted on the tabernacle not directly on the mast. This prevents the boom loads from being transmitted to the mast and pushing it forward and destroying the column loading on the lower section of the mast. Take a look at most carbon mast breaks and if there is no fitting failure the great majority of the breaks occur at
the lower spreaders. This is because in a puff the mast head rigs pull the top forward at the Masthead and the boom is pushed forward at the bottom and the mast is put into an “S” with the hard point being at the lower spreaders. With the tabernacle absorbing the boom loading and the prebend it is almost impossible for this condition to occur. Also mounting the boom approximately two feet in back of the mast and having it pivot there has two additional benefits. The first is that it allows the boom to swing farther out before hitting the spreaders. The second is that when the boom does swing out it automatically adds draft to the sail since the pivot point itself is now asymmetrical because the radius of the swing is no longer at the mast but in back of the mast. Unlike most rigs where the mast is straightened going downwind and the out haul is loosened the RT55 maintains the prebend and adds draft by the asymmetrical swing of the boom. The conventional rig raises the center of effort going downwind, the RT55 keeps its center of effort low and the deep draft and large amount of prebend keeps the air in the sail providing lift instead of letting it escape around the front creating those wild
gyrating rolls like a conventional rig. The problem with a rig with no backstay is that it is almost impossible to get enough head stay tension. In the RT55 this problem is addressed by running backstays which will create enough headstay tension while going upwind, though the rig does not depend on the runners to stay up. The carbon in the hull structure combined with the prebend of the mast allows the head stay tension to be at least as tight as in a conventional rig. The head sail is very small at only 610 sq. ft. and is mounted on a roller furler. Tacking is very easy and the boat is so easily driven that you can
still make good speed in light winds but can also keep the working sail area up in a wide range of wind conditions when combined with the water ballast. In essence the first reef is adding water ballast.
2023 Update: We’ve taken out the massive pump and much of the wiring that the old system required as the last owner (and likely the one or two before too) just used the manual valves. The original system was modern for the time but quite complicated, requiring AC power to actuate the valves and a lot of wiring. We’re working with Paul Bieker and other Riptide or water ballasted boat owners to design a system that works simply and efficiently and we can’t wait to get it up and running.
In order to maximize going upwind and power reaching the RT55 uses water ballast. The amount of water ballast is moderate at 1600 lbs. and reduces the angle of heel by about five degrees. The water
ballast is mounted in the aft flared section of the hull in the aft cabins where it will exert the most leverage. Most ultralights are not known for their windward abilities, the water ballast allows the RT55 to power up and develop driving force similar to a much heavier displacement yacht. As an example, when returning to Seattle from Hawaii there is an approximate three day beat to the north that starts the trip. In the RT55 you bring the angle of heel down under a reefed main and jib to a comfortable 15 degrees but the water ballast combined with the low center of gravity, deep “V” sections and centralized weight displacement will develop the power you need to make miles to windward in trade wind conditions. This is where the last generation of ultralight cruisers become almost uninhabitable, even when motoring to windward. By being able to use water ballast to power the boat up on a reach and keep the boom from dragging the potential of breaking the 300 mile per day barrier for a cruiser is now possible in trade wind conditions.
The water ballast system is a fully automatic system that is push button activated in the cockpit by the winch islands and is managed by a Programmable Logic Controller (PLC). The system is designed to either have the tanks full or empty. If a tank is desired to be full the system will automatically fill the tank desired and shut off when full. If a tank is to be evacuated overboard or transferred to the opposite side a push of the button starts the cycle and will stop it automatically. There is a flow sensor wired into the PLC to protect the pump and electronically actuated ball valves control the water flow. All the equipment is
industrial grade and the ball valves are NEMA IV rated. The ball valves have a manual back up and in the event of a total power failure the tanks can be evacuated by the manual bilge pump.
The underwater foils were optimized to provide lift andreduce drag. Drag is a particular concern as your speeds begin to climb because drag increases by the square of the speed. The low wetted surface
will be a benefit here but a big culprit to maintaining top end speed is the drag of the keel. The other purpose of the keel is to provide lift. Broad sterned boats when they are heeled have a “virtual” hull shape driving the boat off to leeward. In low speed conditions these boats need to be powered up by sailing at almost reaching angles. Some of the more extreme boats are not able to produce enough lift in low wind conditions and are sometimes at the back of the pack in these conditions. This is why it was decided to use a trim tab. The trim tab allows the keel to be only 39 inches wide, including the tab, and by greatly reducing the surface area the upper end downwind speed is increased and the low speed windward performance is enhanced. Even more important for a cruising boat when going to windward in sloppy and steep seas it is possible to point the boat a little lower and power up the sails and then crank in two to three degrees of tab angle and still maintain a high VMG to windward.
The foil section of the keel is a moderate laminar flow Eppler Section. This section has nearly the same lift characteristics as the standard NACA foil sections that are now common in turbulent or non laminar conditions and in a laminar flow condition the drag is much less than with a NACA foil section. The trim tab can induce the laminar condition at very low speeds by getting the foil to “suck” very quickly. To add to stability and maintain a low center of gravity a bulb was placed on the bottom of the keel. The bulb is approximately 6500 lbs. and is all lead. The keel strut weighs approximately 1400 lbs. and also has an additional 700 lbs. lead poured into the bottom of the keel. The total weight of the keel is 8600 lbs. The keel strut is welded out of mild steel and is galvanized and then coated in epoxy. The keel is mounted in an aluminum Crash Box that is bolted into a carbon fiber grid. The keel Crash Box protrudes approximately 18 ” into the boat and the aluminum structure takes the side loads. The keel is held in place by three pins and is designed to pivot like a centerboard in the case of a grounding in order
to absorb the loading. The aft lower pin is the pivot pin, the upper front pin is the “Fuse” pin and is designed to deform or break in a catastrophic grounding that exceeds 12 knots and allows the keel to pivot and the lower pin is bushed in a UHMW race that absorbs and controls the aft rotation of the keel strut. In this condition the keel has pivoted approximately 20 degrees but the boat can be sailed or motored in this condition and is structurally sound. The pins can be removed and the keel rebushed and reinstalled. Also this set up will allow for a modular keel such that a person could easily fit the boat with a keel strut to allow for a 6 foot draft. Also a person who wanted to motor the canals of Europe could easily remove the bulb and strut and carry the strut in the dinghy garage or ship it to a yard on the Med or Baltic bolt the bulb back in place on a very short dummy strut and have a very safe boat to motor with less than three feet of draft.
The RT55 has dual rudders for increased control. These rudders are specially designed foils in their own right. The foils are mildly asymmetric and are designed to gently push in towards the center when going straight. This centerline lift adds directional stability similar to the feathers on an arrow. When the boat begins heeling and the speed is increasing, the leeward rudder is immersed in the boat’s pressure wave on the stern and the windward counteracting lift characteristics are reduced. The lift of the leeward rudder is also increased by the square of the speed and as a result whether helm is now induced by speed as opposed to rudder angle. By not having to crank in a lot of rudder angle drag is greatly reduced and the boat balances similar to a full keel boat. It is possible in even robust conditions to set the sails and leave the helm for extended periods of time before steering corrections are made. Also most rudders have a very narrow drag bucket. This is why those helmsman who are truly talented can excel because they are able to control the direction of the boat by keeping their rudder corrections inside the angles of the rudder’s drag bucket. Those of us less talented make our steering corrections outside of the drag bucket and will slow our boat down. By having mildy asymmetric dual rudders the drag bucket is effectively doubled so those of us that are less talented helmsman now have a much larger drag bucket in which to make our steering corrections. The rudders tubes are autoclaved sections with a wall section of .875 inches (22mm) mounted in heavily reinforced tubes with dual sealed bearings.
The deck plan and sail controls were designed to accommodateshorthanded cruising. There is a winch island aft of each helm station. This configuration allows the helmsman to effectively tack and jibe the
boat with the sail controls close by. No more having to run around the front of the wheel to trim the mainsail and jib. By having a separate helmsman area aft it allowed the cockpit to accommodate high secure sides unencumbered by winches and sail controls. The off watch crew or guest in the cockpit are no longer in the way when the boat is being sailed. The cockpit seats are six and a half feet long so that a second crew member can be sleeping in the cockpit while the helmsman keeps an active watch. This feature can be appreciated on long passages with a short handed crew. The walkways on the side decks are secure and wide open. The sails are raised and lowered at the mast. The only way one person can truly lower, raise and reef the sails is with the winches the halyards at the mast. In order to lower sail with the halyards at the cockpit two people are required. By placing the winches on the tabernacle above the deck they are conveniently placed for winching up the main and asymmetrical sails. The boat is also designed to be reefed at the mast. It was felt that a simple slab reefing system operated at the mast was far more reliable than a single line reefing with their double internal blocks that have a much higher probability of jamming and greater internal operating loads. When you want to put in the third reef the wind is approaching extreme conditions and the last thing that is needed is to be fussing with your reefing mechanism. You want the sail secured quickly and easily and to get back into the cockpit.
There is an arch over the aft end of the cockpit. Electronics such as the radar and antennas can be mounted on this arch but the real purpose of the arch is to serve as the hard point for a dodger. Special coamings are incorporated into the deck forward of the hatch to accept this dodger. When fully deployed the dodger would enclose the entire cockpit. In the tropics this dodger would act as a bimini and when motoring up the inside passage to Alaska on a drizzly day the covered cockpit effectively extends
your interior space.
In the forward section of the boat is a sail and storage locker. The asymmetrical spinnaker has a bin in this locker so that it can be raised and lowered directly out of the locker. One person can easily douse the asymmetrical by collapsing it with the sock and then loosen the halyard and stand in the sail bin and pull the sail directly into the bin as you ease the halyard. The asymmetrical spinnaker can produce motoring speeds in as little as eights knots of true wind. Being able to use this sail effectively can make passages through the equatorial areas and the Pacific High much more pleasant and fast.
Forward of the sail locker is the anchor locker. The primary anchor is a 66lb Bruce on a 100 feet of 5/16 inch high test chain which is attached to 300 feet of 5/8 inch nylon rode. This anchor is a massive anchor for a boat this weight and is often used on boats weighing three times as much as the RT55. The anchor locker has a Lewmar Concept II anchor windlass controlled by a hand held control. The Lewmar Anchor Windlass has a special rope chain gypsy so that when raising or lowering the anchor there isn’t any reason to fuss with switching between the rope and chain gypsies. The anchor locker is tall, narrow and deep so that the chain and rode will feed easily. Also the anchor locker is totally self contained with its own overboard drains so that there is no water intrusion to any other areas of the boat during heavy weather. The anchor is securely held in place by a special custom fitting that fits into the bow prodder.
In order to accommodate one of the more difficult problems of storing a useable dinghy, a dinghy garage is provided in the stern of the boat. This area will provide for a 12 foot special designed hard dinghy or else a Rigid Bottom Inflatable with the tubes can be deflated and stored in this area. At the end of your long passage you can now have easy access to a useable dinghy.
The Riptide 55 is powered by a 70 hp Isuzu 4JB1. This engine is anon turbocharged engine and is a common industrial engine used all overthe world. In generator service this engine is rated at 20,000 hoursbetween rebuilds. The injector pump and the injectors can be disassembled and reassembled without any special tools, a real benefit in any third world country. At 2000 rpm in flat water this engine produces motoring speeds of approximately 8.5 knots with a two bladed max prop with fuel consumption being a little over a gallon and a half per hour. At 1800 rpm fuel consumption decreases such that the range is almost a thousand miles with the 133 gallons of fuel. Top speed is well over 11 knots at 3000 rpm.
The engine is located close to the center area of the boat and the galley sink is over the engine compartment. The engine is well ventilated from the deck and has a large exhuast fan. The engine compartment is modularized such that the galley sink is removed from the top easily and
all the panels can come off. In less than half an hour the engine is fully exposed and could be removed. For routine maintenance there are access panels on all four sides. Oil can be changed, valves adjusted and belts tightened with ease. The engine compartment is heavily insulated for noise control.
The RT55 was designed to be comfortable at sea as well as port. The combination of the forward owner’s cabin and aft state rooms gives a good combination of port and sea berths. The forward
owner’s cabin is spacious with a full size centerline double bed (no having to crawl over your partner when getting in and out of bed). Excellent ventilation is provided by the overhead hatches and overhead vent. Aft is two cabins each with double berths and plenty of storage. At sea the aft cabins provide comfortable and secure berths for the off watch crew.
The RT55 features one generous sized head with a separate shower stall and centerline head for ease of use no matter what the conditions are. The feeling of openness and airiness is increased by the added ceiling height of the mast tabernacle. Enclosed in the mast tabernacle is a vent fan and hatches that can remain open on the leeward side to provide ventilation.
Opposite of the head are lockers for additional storage and spares. Aft of the head is a salon which serves as a generous gathering place. Across from the salon table is a settee which serves as a nice reading area or sea berth with a lee cloth. Aft of the salon is the galley and nav station areas. The galley is “U” shaped in order to be secure in all conditions and the sink is almost on the centerline. There is a 5.7 cubic foot refrigerator and separate 4.5 cubic foot freezer. These boxes are cooled by evaperator plates that are driven by a high efficiency hermetically sealed 110 volt unit. Also in the galley is a three burner Force Ten stove. There is extensive storage and locker space. Over the sink is a special dish drying cabinet to store your dishes at sea or in port. This locker is designed to place your wet dishes in directly from the rinse and to allow them to air dry so that they are ready for the next meal. Across from the galley is a pantry area for the storage of food and staples.
Next to the pantry is the nav station. This area is designed to be large enough to serve as the ship’s office and communication center. The nav station table is large enough so that a full size chart can be studied and the vertical area adjacent to the nav table is designed to take a full complement of communication and navigation instrumentation. In between the nav station and pantry is the electrical panel which is divided into three DC load groups and a separate AC panel.
The interior walls have a light colored architectural finish to give light and style to the interior. The galley, salon and nav station area feature mahogany skinned veneers over nomex cores for a lightweight and dramatic interior finish. The head area and other cabinets are Awlgriped for durability. The overhead liner is a leather look vinyl for durability and is trimmed in mahogany. The counter tops are of high pressure laminates for style and durability. The cabin sole is painted in Awlgrip and is light textured for nonskid footing and is extremely durable and easy to maintain.
Electrical and plumbing systems are designed to provide long term cruising capability. The RT55 carries 133 gallons of fuel (503 litres). 120 gallons (454 litres) in integral tanks and 13 gallons (50 litres) in a day tank. The integral tanks have clean outs in the tops. The use of a day tank minimizes problems with dirty fuel and algae growth. There is a fuel transfer pump which can be operated from the cockpit. The fuel is filtered with a 30 micron Racor filter as it is pumped into the day tank. Between the day tank and the engine is a 10 micron Racor filter where at the engine the fuel is filtered to the manufacture’s specification by the engine filter.
The electrical system consist of three battery banks and two alternators to charge the system. The house bank has three 8D gell cells in parallel for a 660 amp capacity. There is additional storage space for a fourth 8D gell cell if desired. The house bank has its own dedicated 210 amp Balmar high capacity alternator. There is a Group 27 engine starting battery and a Group 27 electronics buffer battery. The engine battery and electronics battery are charged by a 35 amp alternator. A 2500 watt Heart Inverter will supply 110 volt power when not at the dock. The inverter has a 130 amp 12 volt charger built into it.
(No longer active) The water ballast system is driven by a 1/2 hp (.4 kw.) 12 volt motor. There are six 110 volt electronically operated ball valves to control the water distribution. The whole system is controlled by a Koyo Programmable Logic Controller (PLC). Protecting the pump is a flow sensor. In the event of a valve failure the valves can be operated by hand and in the event of a total power failure the system can be evacuated by the manual bilge pump. In an emergency situation the pump can be disconnected from the (PLC) and can serve as a very high capacity bilge pump. The system is push buttoned operated at panels located in the cockpit.
The head is a Lavac unit and is electrically activated. The Lavac unit was chosen for its reputation for reliability. The head is operated by vacuum and there is no moving parts. The pump is a large bilge pump and is extremely rugged and has a clean out provided. Directly in back of the head is a panel that controls if the sewage is pumped overboard or into the 54 gallon (204 liters) integral sewage tank. The pump on the Lavac unit also serves to pump out the sewage tank overboard and is operated by
the control panel in back of the head. There is a dock side pump out provided.
The fresh water system carries 90 gallons (340 litres) in two 45 gallon (170 litre) integral tanks built into the cabin sole, 2 and 11 gallons (41 litres) in the water heater for a total of 101 gallons. It is anticipated that the aft water tank will serve as the tank to receive the output from a water maker. There is a water distribution manifold on the intake side of the pressure system to control which tank is being used. In addition to the pressure system are 2 manual pumps in the galley and the head. These pumps will serve as backups in the event of apressure failure but also can be used to conserve water usage by turning
of the pressure system.
The salt water system is an on demand pressure system with three taps. One in the anchor locker for anchor and deck washdown, one in the stern for deck wash down and one in the galley.
Length overall: 56.0
Length fairbody: 54.5
Length waterline: 53.0
Maximum beam: 14.7
Water ballast:1600 lbs per side
Sail area: working = 1480, maximum offwind = 3094
I: 60.5 J:26 P:57.6 E:20.5
70 hp Isuzu
Hearth HBW 250
Fwd. Reduction Ratio – 2.01/1.00
Shaft – 1 3/8″ Aquamet 22
Strut – Cast Bronze
3 staterooms, one forward, 2 aft
One head, Lavac electric and a stall shower
Heating system: 45000 BTU Webasto DBW2010 (new in 2022) with four radiator fans
Hotwater – 11 gallon Torrid with Stainless Steel Jacket. Tank is heated by either shore power, engine heat exchanger, or Webasto heater.
5.7 cubic foot box for refrigeration with one plate run by a SeaFrost BDXP system, water or air cooled.
4.5 cubic foot freezer box with two evaporator plates SeaFrost BDXPX, also air or water cooled.
Fridge and freezer have at least four inches of foam insulation surrounding them and drain to bilge.
Force 10 three burner gimbaled stove with oven and broiler, fueled by propane.
Two fiberglass Viking propane tanks with regulator and solenoid in starboard seat locker.
Fuel: 133 total gallons, in two 60 gallon integral tanks and a 13 gallon stainless steel day tank
Water: 90 total gallons, in two 45 gallon integral tanks
Holding: black water, 54 gallons, integral to hull
Electronic and navigation equipment
WS Sensor – B&G
Speed Sensor – B&G
Depth Sensor – B&G
Fluxgate Compass –B&G
Cockpit Displays – B&G
Four Dual Displays in Cockpit
Radar – B&G
GPS – Garmin 120
VHF – Icom
Shore power: 110v or 220v
House Bank – Three 8D AGMs
Engine Starting Battery – Group 31 AGM
Electronics Buffer Battery – Group 31 AGM
Alternators and Charging
Main Alternator – Balmar 210 Amp directly charging the house bank
Secondary Alternator – 35 Amp charges the engine starting battery and electronics buffer battery.
The secondary alternator can charge all banks and the engine can be started and the electronics can run just from the house bank.
Shoreside charging is done by the 2500 watt Heart Inverter which has a built in three step multi level 130 amp charger.
120 AC systemShore Power is supplied by a 30 amp supply
The Inverter is managed by the Link 2000 mounted directly in the panel and charging is supplied by the inverter.
Distribution is by two custom panels by M and I Electronics. One panel
is for the 12 volt DC distribution and one panel is for AC distribution.
6 – 8″ Schaffer Aluminium Cleats
30″ High Schaffer lifeline stanchions with boarding gates
Custom made bow and stern pulpits
Swim Step off of Dinghy Garage
4 – Lewmar Coastline 040
4 – Lewmar Coastline 010
6 – Lewmar Coastline 020
2- Lewmar Atlantic 010
1- Custom Sail Locker hatch by Lewmar with Kevlar and Nomex cover instead of acylic for weight savings
All hatches except for the sail locker hatch have special order white frames with custom rose bronze acrylic windows.
Sails and rigging
Main: 880 square foot Fusion by Quantum. Carbon fiber/Technora/Mylar laminate. Mast Track System is by Antal with Batten attachments by Sail Power Systems. Mainsail has three sets of reef points.
Jibs: Working Jib is 600 square foot fusion by Quantum, with foam padded luff for furling.
3 spinnakers of various sizes and weights
1 Code Zero mylar laminate on furler
1 Storm Jib
1 Storm Staysail
1 Storm trysail
Jib Sheet – Harken 56STA
(2) Main Sheet – Harken 53STA
Main Traveler – Harken 45STA
Halyard – Harken 45STA Electric
Spars and rigging
Spar – Carbon Fiber Spar by Hall spars, dual spreader with running backstays. Six Lewmar Halyard Clutches on mast. Lazy Jacks with internal mast feed act as topping lift and assist in furling.
Standing Rigging – All standing rigging is rod rigging by Navtec with the exception of the removable inner forestay, which is Kevlar
Runners – Running Backstays are Kevlar by Navtec.
Boom – Carbon fiber boom with foam core reinforced with plywood in high
Running Rigging – All Running is by Samson as noted below:
Main Halyard – 7/16″ UltraTech
Jib Halyard – 3/8″ UltraTech
Spin Halyard – 5/16″ Spectron dacron cover
Genoa Halyard – 5/16″ Spectron dacron cover
Mainsheet Sheet – 1/2″ XLS
Main Traveler – 7/16″ XLS
Running Backstays – 1/2″ UltraTech
Jib Sheets- – 9/16″ XLS
Spinnaker Sheets – 1/2″ XLS
Pole – Carbon fiber bow launched asymmetrical spinnaker pole. Pole is extended by single line pull.
Port and Starboard Ballast Tanks of 200 gallons each located in the deck hull corner in the aft staterooms
Dual rudders. Rudders are asymmetrical to provide mild lift.
Rudders are by Advanced Composites and have 3.5″ outside diameter shaft
with an autoclaved carbon wall thickness of .875″.
Steering system has dual outboard pedestals and is a rod linked cobra
system by Whitlock with rack and pinion inputs in the pedestal heads.
There are two 36″ destroyer type wheels.
Each pedestal has a Ritchie Compass mounted in the pedestal.