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FPB 64 Intro
FPB 64 - FAQs
I was wondering if your team considers the FPB 64 a live-aboard boat? I know the 83 is sitting idle right now (during the winter) in Southern California.
We'll start with an answer on how we have been using Wind Horse. When our kids first took off for college (a long time ago) we rented our house and took off for what we thought would be full time cruising. However, we missed the family so much that we needed to split our time between the boat and land. With our last boat we used her in three to four month periods, then put her into storage mode wherever we might be returning to land for three to four month periods. The layup process took two days of hard work - the same time applied after our return to the boat for commissioning. So, one of the design goals with the FPB was to make her easy to mothball. Pulling up to the marina or travel lift at 0800 and be in the cab to the airport at 1200 was the goal.
Fast forward to the present and we still have non-boating demands on our time. In addition to parents, siblings, and children, there is a new, younger generation that we need to frequently hug. However, Wind Horse is more alluring (although we hate to admit it sometimes) than our previous boats and we are spending substantially more time aboard her than in the past. Our pattern is changing to where we are no longer enamored with the house (this applies to BOTH of us) and prefer our time aboard. So, the visits to see family are going to happen more and more from the boat, leaving her for shorter periods of time.
Now to the original question, is the FPB 64 a full time live-aboard design? Of all the boats we have done, this is the best full time cruising boat. We say this because of a couple of design factors.
One is storage space. If you are going to spend full time on the boat you need more space. Not for the boat's gear - because that is a constant regardless of how the boat is used - but for things like clothing, office records, and other stuff which we all seem to "need" these days (such as a complete array of galley tools). The FPB 64 has more easily accessed storage than any boat we've been associated with or visited. And then she has her "basement" for bulk storage.
Most of our friends who cruise are like us in that we all have outside commitments as well as hobbies which require space to work on. This need is what has led to the office aft on the starboard side. Of course we've had small office areas on all of our boats (not so small by boat standards - but nothing like what we are used to on land). The FPB 64 office, with its six feet (1.8m) of desk space, long shelf for books, file drawers and shelved areas below the desk for computers and printers is perfect for work and hobbies. That the area is out of the main living area is a further benefit in that it can be left messy if desired. For working on our photography and designing at home we have an array of large monitors. We have to downsize this gear on the FPB 83 (we have a 17" laptop and 22" second monitor in her office). With the FPB 64 we've got space for a pair of 30" monitors and a large printer. Heaven!
There are other factors like the huge fridge and freezer capacity, entertainment gear, and the galley layout (which has counter and storage space similar to a home.
Bottom line, if you want to combine offshore capability with full time live-aboard design, the FPB 64 is as close to perfect as we've come.
We've been sailors all our lives and always looked somewhat askance at power boats. As sailors, how have you handled this transition?
That is a perceptive question! Part of the answer is that we love what the FPB allows us to do, which is cruise to areas we would miss if we were still sailing, and continue to cross oceans without crew as we "mature". Part of the way we deal with this comes from the way the FPB looks. Nobody is going to mistake it for an ordinary motor yacht. And part of the answer is knowing that this seagoing design is even better suited to adventurous cruising than any other vessel we've ever been aboard. Bottom line, comfort and security go a long way towards helping with the transition.
Why the focus on heavy weather in the FPB design, especially since you say truly dangerous weather is rare?
You've hit the nail on the head with that one, and this goes to the heart of our concept. First, there is an emotional issue. We want to know that the boat we are on reduces weather risks to a minimum in the same manner that the 12mm bottom plate reduces risks from floating objects we might run into. There's a feeling of comfort which comes from this knowledge that transcends every other facet of passaging.
And here is the cool part: the same characteristics which give us the heavy weather capabilities also contribute to every day passaging comfort. The stability curve gives the boat a reasonable ride even in 20 foot (6m) beam seas. The ability to run off before the wind and waves at speed, under control, means tradewind passages, or just running before a moderate gale is still comfortable. The fact that the balanced hull tracks so well means little rudder input is required which in turn increases comfort (rudder force tends to heel the boat requiring stabilizer correction).
Trawlers face a different set of motion parameters (we've discussed this in detail elsewhere). Beamy hulls have high initial stability. If you couple their excess beam with center of gravity low enough to create a safe boat in heavy weather, then the motion becomes too violent to be comfortable (or safe). So, the center of gravity is raised to soften the motion. Raising the CG in this manner is fine for protected waters, but it reduces or more typically eliminates the ability of the boat to recover from a knockdown, which we do not feel is acceptable for offshore passaging. There is no way around this conundrum, except to accept the fact that under some weather conditions those boats with high CGs to soften motion will not come back from a knockdown.
Some of your drawings show two dinghies and kayaks. Why so many small boats?
For serious cruising we've found two dinghies are a must. You need a second as a back up, and if there are two aboard, they can be optimized for different things. For example, the main power dink shown on the port side in our drawings, is going to be too heavy to pull up very far on the beach. It is also going to be hard to get out of the surf if you are landing on a beach with waves. The rowing dink - the one shown is a Gig Harbor 15 - is what we use to take to the beach because it is easy for us to drag above the high tide line. With its sliding seat it is also a great exercise machine and a fun way to tour the anchorage. The kayaks are there to show you can have three types of boats. But you might use those house side racks for sailboards or surfboards.
In your web page on cruising range you have some astonishingly low figures for fuel consumption. These are a fraction of what others in the industry claim. How can you know these are accurate and why should we believe them?
First, we've been using several sets of software for many years to predict hull drag and performance. Our designs have always come out very close to predicted. On the FPB 83 we did a series of tank tests and CFD analysis which agreed with our in house analysis. Next, we have very good data on the FPB 83 with 25,000+ miles of experience. If you leave Hawaii with full tanks, then refill when you arrive in California, and divide by the engine hours, you know the hourly fuel burn - exactly. For the FPB 64 we have the same software, and as a double check we've had our prop efficiency numbers double checked by outside consultants. We can also ratio from the FPB 83. If you go back and double check the range page you will see there are three sets of numbers: smooth water, smooth water with an allowance for auxiliary loads, and then the total of the two preceding with a 15% allowance for weather. The third, conservative number, is the one to use for planning purposes.
With fuel prices flirting with $100 per barrel, are you concerned with the cost of cruising on the FPB?
When we first looked at designing an Unsailboat we spent a lot of time running operating costs numbers, looking at cost per mile, and per year, and relating these to different speeds. Since we had never done this with any of our sailboats we decided to go back and check what it cost per mile for their operation, taking into account amortization and repair of sails, rig and rigging maintenance, and the engine room gear. Turns out that the FPB running at 11 knots is about 60% of the cost of operating a sailing yacht like Beowulf, so we stopped worrying about the per mile costs.
When we stopped in Hawaii to rest up and top off our tanks before our leg to California, we paid US$3.00 per gallon, the most we've seen so far for diesel. This works out to $1.82 per nautical mile running at 11 knots and burning 6.7 US gallons per hour. Add in another fifteen cents per mile for oil changes, a yearly check by a mechanic, and rebuilding engine and transmission at 20,000 hours and it is still much less costly than sail.
We are headed to the UK this spring and will be paying probably double what we've been used to for fuel. We can offset this by slowing down from 11 knots to nine.
The matrix above is for the FPB 64 at various speeds with an allowance for auxiliary consumption (generating power and hydraulic loads). This covers only fuel costs and will show the relationship between cost and speed.
One other factor to consider is fuel capacity, range, and the ability to wait until you get to places with better fuel prices. For example, Wind Horse sits with half tanks right now because a couple of hundred miles south, in Ensenada, Mexico, we can buy good quality diesel for a third less than where we are presently located. The last time we filled the tanks was on the Alaskan Panhandle, a long way away!
There is much more information pertaining to this under "Range" on the sidebar above.
I see you have been cruising in Alaska. What do you do about condensation with all those windows and the aluminum hull? We have two friends with fiberglass boats and these sweat like crazy in cold water. My wife is allergic to mold, and we cannot have a moldy boat?
Looks like we are in the same boat (pun intended). Linda is allergic to mold as well, so reducing mold risks has been a focus for a long time.
There are three parts to the answer. The first is that we design our boats so there are NO BILGES within the living areas of the boat. The entire area under the living area cabin soles are tanks - fresh water for and aft and fuel under the salon/galley basement. Eliminating the bilges gets rid of a potential mold growing area which is impossible to correctly inspect and keep clean.
Next, the aluminum inside of the living area is almost totally covered in insulation. This extends even to the deck stringers and hull longitudinals. The same approach will work with fiberglass as well. This insulation reduces heat loss, and condensation.
Next, if it is cold and damp, we will run the air conditioning for short periods when we are showering to pull the extra moisture out of the air. When there is a kettle going in the galley, or we are cooking pasta, the galley/salon air conditioning units are installed so that they do a good job of keeping condensation from forming on the windows. If the windows are starting to fog, running one of the two air con units for a minute or two is all it takes to clear them.
Finally, we carry a home style dehumidifier, installed in the basement. When we are under way in cold and damp conditions this is running. We also use it when the boat is in storage.
Wind Horse has ballast tanks in the flying bridge seats. Will you have these on the 64?
We fitted ballast tanks up high on Wind Horse in case they were needed to soften her motion when she was fully loaded with fuel. Full tanks equate to a low vertical center of gravity which ends up with a quicker motion. We were not sure if they would be needed, but we figured we better have them, just in case.
We've experimented with them in all sorts of sea states and loading situations and the bottom line is that aside from the above mentioned experiments, we have not used them at sea. They have been filled a couple of times in bouncy anchorages, but the 64 will need them less in this situation than does the 83. With so little potential use, the space, cost, weight, and plumbing complexity makes it better to leave them out of the 64 spec.
I don't really understand why you need so much fuel capacity. If most long passages are under 2000 miles, what is the point in being able to go 6000 miles?
Those huge fuel tanks (3400 US gallons) are there for several reasons. First, there are some really long passages you might want to undertake. New Zealand to Panama or Chile for example, or Argentina to the Azores near Europe. Second, you cannot always find fuel at reasonable prices. The capacity gives you lots of options for finding the best deal. Another issue is security. If need be, that fuel capacity could last through several years of cruising during a fuel scarcity. And finally, if weather or schedule warrant, it gives you the ability to run fast at inefficient speeds.
The negatives are slight. At 9.5 to ten knots the drag of the extra fuel is on the order of four to eight percent. Not significant in terms of cost or actual fuel burn (and you do not have to carry the fuel). There is also a storage penalty in the "basement". Smaller tanks mean more space for stores here. But the FPB 64 already has more storage space than will probably ever be used, so this is not an issue.
Bottom line, the enormous capacity/range significantly expands what we can do with the boat and our ability to pick and chose when and where to buy fuel. We think this is all to the good.
Have you made provisions for a safe on the FPB 64s?
Over the years we have fitted safes to many of the yachts we've built for clients. However, theft while we are off the boat, where a safe might be of some value, is not our main concern with the FPB 64. The nature of the construction - tough metal structure and 3/4" thick windows - does not lend itself to break ins. Plus, there is an alarm system.
Of bigger concern is what happens if you are on board and there is a robbery. However, we have several things going for us here. First, the natural look of the boats - Wind Horse is often mistaken for a military vessel (once by the Mexican Navy!) - should be off putting to the bad guys. If you don't know what lurks behind that mean gray hull, why take a chance?
In the same vane, the alarm system plus ease of securing the interior (compared to most boats) is a significant plus.
Coming back to your question of safes should should you feel that a safe is warranted in your cruising plans it can be easily added.
I have noticed steps from the deck to the flying bridge at the forward end of the house in some of the pictures of Wind Horse. In other photos they seem to be gone. Do these fold away and what have you allowed for on the FPB 64?
We originally had a permanent set of steps with handrails from the forward deck to the house top. However, these were rarely used so we put them into storage (we prefer the clean look of the boat without them). They may go back on deck before we head for Europe, or they may not. When we need to go forward with the awnings set we either "duck walk" under the awning, or hop on/off the house roof from/to the coamings.
On the FPB 64 we have allowed for a hinged step system. When you need it it will be easy to deploy (much like a stern step swim ladder). The rest of the time it will be out of the way.
I have been reading about your planned trip to the UK this summer. It seems to me like 8000 miles in six months is pretty ambitious. How do you handle the watch standing and will there be much time for sight seeing?
One of the key factors of cruising with the FPB is how easily the boat is moved, and how comfortable the FPB makes its crew. Out of the six months this summer we will be cruising, only 30 days will be spent under way. Of this time, just the passage from Panama to the Bahamas is apt to have us waiting for it to be over. Otherwise, we'll be as comfortable at sea as we are at anchor, except for our sleep patterns. There will be just two aboard - that is the way we always cruise.
We stand watches of three hours at night, and typically do not keep a formal schedule during the day.
Now, think of what we get to experience during the five months we are at anchor. First, we'll enjoy the Bahamas for a week or two (we have always had too deep of a draft to cruise the Bahamas in the past). Then we'll have two to four weeks for the wonderful island of Newfoundland. The goal for the trip, however, is southern Greenland where we will hang out four to six weeks, depending on ice conditions. After Greenland, if we are late in the summer, we will head direct to Western Ireland, and then cruise south, around the bottom of Ireland and England, before ending up in London for the winter.
Sounds ambitious, but we know from experience this will be a lot easier on us than some of our cruising cycles under sail, and we get to experience so much more in terms of geography, weather, and people.
Which is why we started down the FPB path in the first place.
I have been thinking about a power boat for long distance cruising, and looking at trawlers. I have also looked at your FPB data. While the FPB seems appealing, I am nervous about being going to sea in such a new concept. Why should I seriously consider the FPB 64?
To begin with, this is not a new concept for us. We've been doing sailboats in a similar vain for 30 years, many of which have multiple circumnavigations under their keels.
Next, the FPB prototype, Wind Horse, has over 30,000 nautical miles of trouble free cruising behind her in the first three years of part time usage. All of this has been with husband and wife aboard. She just completed (June 2008) almost six thousand miles from California to Nova Scotia, in six weeks (with a week in Panama and 2.5 weeks in the Bahamas along the way).
Just as Wind Horse is a refinement of our many sailing designs, the FPB 64 is a further refinement of the FPB 83, based on what we have learned in the past three years. If you will go back through the data on the FPB 83, you will find that she hits her performance numbers in terms of miles per day actually achieved, and fuel burn. The FPB 64, with such a close sister ship, is a lot easier to engineer.
These boats are a lot more svelte than the trawlers you may be used to looking at. Fat boats are fine at anchor,and look great in boat shows. But they are hard to steer offshore and uncomfortable in even modest sea states. Our preference has always been to cruise in a boat which maximizes passaging comfort and minimizes heavy weather risks. If the boat is comfortable, and feels secure, then it is going to get used. Witness the brief cruising history of the FPB prototype.
A final word on slenderness ratios. The FPB Series may look skinny, but most commercial vessels are even narrower for their length, with beam to length ratios of ten or more to one. Slender waterlines are more easily driven, and more comfortable, and lot easier on their crews in heavy weather.
My wife and I have been following Wind Horse's recent trip to the East Coast. We've done some cruising ourselves, and are amazed that a crew of two can make such a passage and not be exhausted. How is this possible?
You're question goes to the heart of our philosophy, and the driving force behind the FPB Series. Make the boat comfortable enough, and fast enough, and amazing things are possible.
To begin with, while long this has been an easy trip. The average speed the FPB is able to maintain means less time at sea and the ability to better use favorable weather patterns. Looking at the Dashew's logs for the trip to which you refer, you find a consistent pattern of easy conditions. This is not luck or coincidence. Rather, it is the confluence of modern weather forecasting and routing with the ability to maintain a fast minimum speed at sea.
Next is the physical comfort of being on passage. If you are comfortable, you relax, spend less energy, and arrive at your destination refreshed and ready to explore (as opposed to needing a period of recuperation).
This comfort comes from a series of design areas, addressed in detail throughout the website. But to quickly summarize:
The above leads to physical comfort. Equally important is the emotional security which comes from the metal hull, double bottom, water tight bulkheads, and ability to deal with nasty weather.
Finally, this recent passage from California to the East Coast of Canada in just six weeks would not have been practical even in one of our cruising sailboats, especially with just a couple as crew. The work load would be too high. But the reduced workload of the FPB Series means the crew's duties center around keeping watch, doing a bit of navigation, and enjoying being at sea. And instead of being a chore, this recent voyage by Wind Horse has been a pleasure.
I am seriously considering a trawler yacht and close to signing a contract. I am intrigued with your design, but it has come to my attention late in the game. What can you tell me that would change my mind?
The right boat for you depends on where you intend to cruise. If you are going to cruise locally, with mainly protected waters and short hops, than almost any boat will get the job done. But if you are thinking in terms of a motor vessel and the open ocean, you should consider the trade offs closely.
We've been doing this for a long time and our own experience, and that of over 50 new owners, is that if the boat is comfortable at sea, and gives you and your crew a sense of security, then it is much more likely to go places. Our sailing designs have a higher percentage of circumnavigations and ocean crossing than any other yachts. The reason is simple, they are easy to handle and supremely comfortable.
Discomfort at sea is rarely dangerous, just unpleasant. But it takes experience to know the difference. It is often the case that one short bout of adverse weather and the crew loses confidence. They don't want to experience that discomfort again, and worry about worst case scenarios.
Which is why so few long distance cruising dreams work out. When we started the FPB Series we had the same goal as always, safe, comfortable, and fast cruising. The FPB 83 has proven this concept beyond what even we expected. The FPB 64 will do equally as well.
To recap, if your plans are local, and your primary goal is harbor hopping, then any almost any yacht will get you there. But if you want to cross oceans, or the tougher bodies of water like the Bay of Biscay, North Sea, Pacific Coast coming up from Mexico, back and forth to the Caribbean or tropical South Pacific, the decision making matrix needs to reflect the realities of wind and wave.
There is a huge amount of data throughout the website on motion, comfort, and safety at sea. If you are seriously thinking of cruising offshore, then it is worth your time to read it, if for no other reason than to establish a baseline from which to judge any potential acquisition.
What about resale value? If I buy a known production trawler, there is an established resale market. But what about with your boats?
This is a question we hear all the time. There are two aspects to the answer. The first is our approach to building yachts. We have never been a volume builder, nor does that interest us. Our model is to produce a few, really high quality yachts, which we would want to own ourselves. We do this on a very efficient basis, including as standard a complete set of ground tackle, spares, tools, and systems, so when the boat is handed over she is ready to go cruising. These boats are efficient to purchase and to maintain.
When we do a series we stop before demand dies down, rather than discount pricing at the end to keep things going a little longer.
The combination of building efficiently, stopping early, and ease of ownership results in high demand on the brokerage market. Have a look around at how our sailing designs do when they become available.
On the other hand, if you buy a volume production boat you have a situation where the market will eventually be flooded with product. In a strong economy you may still be OK, but when the economic cycle turns, you find yourself competing with a lot of other sellers, including the builder, who is now desperate to move product.
How many amp hours per day do you expect to consume, and what has been your experience with the FPB 83?
With the FPB 83 we've been using between 225 and 300 amp hours (24 volt system) per day. This is much higher than what we've been used to in the past, but is a fraction of the 600 to 900 amp hours common with many yachts that are generator or shorepower dependent.
How much generator time are you seeing on Wind Horse?
The norm so far has been to run the genset every other day, usually at dinner, while the wash/dry cycle is going on. We often watch a movie on the 42" plasma TV during this period, and with what is left over from the genset capacity, put some charge back into the batteries. In 17 months of full time use we have put 200 hours on the generator.
After so many years of using propane for cooking, why are you switching to electric with the FPB 64?
We started thinking about this during the summer of 2007 when our propane oven quit working (for the second time). We've never been happy with the temperature control on propane ovens, but this turn of events forced us to use the microwave for a lot more than usual. Which in turn got us to consider how efficient our electrical system was. So we started logging propane burner time and converted this to what it meant in terms of daily power consumption. Turns out that the typical cycle in the galley was five meals requiring modest power and one large meal every two days. Assuming that major meal takes place during the normal evening generator run, this translates to an additional 15 or so minutes a day of charging required to put the extra amps used for cooking back into the batteries. If we were moving the boat every few days, then we would not even need to use the genset (there is plenty of battery capacity for the inverters to go two or more days before the batteries need a charge, even with electric cooking.
The big advantage here is getting rid of the hassle of refilling and storing propane, and the explosion risk, however minor, which comes with this gas.
Can you fill me in on the cooking gear being supplied?
We will be using an "induction" stove top, three burner model. We've tested these and they are at least a third more efficient than conventional electric stove tops. The induction top also has the advantage of not heating the stove surface, a safety factor at sea. The oven specified is a combination microwave/convection unit, with built in broiler. These units use efficient microwave energy for most of the cooking, and the convection heat for browning (and baking). We also consider the propane fired BarBQ on the aft deck part of the galley gear.
I don't like concept of cooking with electricity. It forces you to have a large genset, and then a back up or night generator. The main genset is hard to keep loaded.
With the normal approach to power boat systems we'd agree with you (and we would stay with propane for cooking). However, a couple of things have happened in the last few years to change the equation. First, electric cooking is far more efficient now that we have induction cook tops and speed ovens (see above answers). Next, the inverter chargers we are using are smart enough to sense generator or shorepower load, and provide extra capacity from the batteries during periods of peak demand. This means the genset can be much smaller than would have been necessary a few years ago, and that we can keep the genset nicely loaded. The 12kW genset specified for the FPB 64 will take care of cooking and other needs, with only an occasional boost from the inverters.
Why is your electrical power consumption so much lower than other boats?
We're not sure why other boats are so high. From our standpoint, we are just building efficient systems, the same as we have always done. These start with our "traction" battery bank. This is one huge, highly efficient battery, with lots of usable capacity (in excess of 1000 usable amp hours at 24 volts). Next are our special fridge and freezers. These are very efficient with their thick isocyanurate insulation and evaporator plate compressors. It would be a lot easier for us to use household gear (which is the norm) but this would increase electrical consumption by a factor of three. There are lots of other factors involved, but the bottom line is our yachts have always been designed to live free from shorepower without being generator dependent.
I have noticed that most high end yachts these days fit Sub Zero fridge systems. Why are you not using this gear?
Sub Zero works great in a house, and has good brand recognition. But in the real world these systems require three times (or more) the electrical power of our custom built boxes. This is because of their door design, and lack of insulation. You can get away with this if you are connected to shore power, or want to run the genset 18 hours or more a day. However, we have always worked on the assumption that we were going to be spending long periods of time at anchor and did not want to run a genset (or be generator dependent - which means at least two gensets are required). It would be simpler for us and far less costly to install off-the-shelf fridge and freezer systems, but this would compromise the basic concept of the boat which is to cruise efficiently and comfortably off the beaten path.
What provisions have been made for maintenance of the engine, genset, and other gear?
To begin with, there is a girder running down the middle of the engine room which can be used for lifting and moving the genset, engine, or transmission. The design of the engine is such that it can be rebuilt in place, as long as you can get access to the underside - which is where the girder comes in (for lifting the engine).
The 12kW genset can also be rebuilt in place using the girder. Or, if the pan is removed, it will come out of the engine room hatch.
How is lube oil - old and new - being handled?
We've got an oil change pump with manifold plumbed to the engine, genset, and transmission. Because the oil change quantities are so small, the easiest system to use is one where old oil is pumped into an empty oil container (built in tanks still require the oil to be pumped into a container for disposal). What makes this work is sufficient space in the engine room for both new and old oil supplies (the FPB 64 has lots of room for a variety of different types of oil - engine, steering, and hydraulic - to be carried at the aft end under the swim step).
What are "traction batteries" and why are you using them?
For a really detailed answer see the chapter in our Offshore Cruising Encyclopedia on battery systems. The short answer is that these are the most efficient, long lived batteries available. The 24 volt house bank is made from a series of 2.2 volt cells, with a special construction that allows them to be deeply cycled - 80% discharge is considered normal. They are guaranteed for a minimum of 1200 80% cycles. The bank is nominally sized at 1350 amp hours based on a C20 rate, which leaves in excess of 1000 amp hours of usable capacity, all in one bank.
You can build up amp hours using lots of smaller batteries and wiring them in parallel, but this never works as well. The series/parallel wiring introduces imbalances into the battery bank and typically reduces life span and capacity, which is one reason other types of systems seem to fail so quickly.
A traction battery bank is not cheap to buy or easy to install. The wiring, service provisions, and dealing with the weight all take time and money. But these traction batteries are at the heart of the systems, and they need to be the best money can buy. It is also an approach that has proven itself on our designs over the past 20 years.
Although there are other types of batteries out there, we have not seen anything which delivers the service life and functionality of a properly engineered traction battery bank.
It seems like a lot of your approach to systems is based on "induction" stovetop cooking. How good is this and do you have any real world experience?
We've been testing a single burner induction cooker in Tucson this winter. It works so well - instant heating, better control of temperature, lower power consumption - that the built in conventional electric stove top has become irrelevant. We've ordered a similar unit for Wind Horse for further testing and to check real world amp hour consumption. FPB 64 Project Manager Todd Rickard has a full on induction cook top at home and has been using it since the fall, He has found the same benefits.
Matched with our traction battery bank, and inverter chargers, this form of cooking is ideal for serious cruising.
Do you have a security alarm system and if so, can you give me some details?
There is indeed a security alarm system. This is triggered with a reed (magnetic) switch on the main door along with a series of deck sensors which amazingly detect slight movement in the aluminum deck. We've used the same sensors on Wind Horse and they work well, without false alarms. The system is turned on and off with a remote. When the alarm is triggered the deck lights flash and a loud signal sounds.
Upon returning to the boat you turning the alarm off turns on the deck lights for a few minutes aiding your boarding in the dark.
I am concerned with the complexity of the systems with the FPB and with my ability to maintain these and keep the boat running while cruising. How do I get over this concern?
The answers to this excellent question lie in several areas. To begin with, although the systems are complete in what they provide they are done in the simplest, most reliable manner possible (simple is much harder to engineer than complex).
With good access to equipment for inspection, problems are reduced or eliminated because they are caught early, before they become major issues. This is why we allocate so much space to systems in the basement and have such a large engine room. Maintenance is also why we do not hide this critical gear behind panels which block easy inspection (but look good in boat shows).
Next, we create a detailed owner's operation manual which supplements many of the documents which come from various manufacturers. This operations manual covers normal operation, inspections, preventative maintenance procedures, along with various fault tracing check lists.
Then there is the training which is included with the your purchase. There is an extensive period of time budgeted with the electricians and systems engineers during the early phase of ownership in New Zealand. We assume this will take place over a period of time as there is a limit to how much you can absorb each day.
There is also a period of training in vessel handling and general operations.
By the time you are finished with this training, which includes fitting major maintenance items to the propulsion engine (like cooling and injection pumps) you will be better qualified than 95% of those who are cruising today
You have spent a lot of time recently in cold climates. But I see now you've been cruising in Panama and the Bahamas at the end of their cruising season, when it is bound to be hot. How have the systems been work?
Normally when you cruise you move slowly. The climatic changes that go with new latitudes come on gradually, and your body has time to adapt. But when you go straight from California to Panama in 14 total days, the hot humid environment of the Panama Canal can be hard to take - you want the air conditioning to work well!
The systems approach we use has to be as efficient as possible in all regards. This integrates battery capacity, charging capacity, air conditioning, heating, fridge, cooking, and many other details in a balanced entity. Do it right, and you can use a smaller genset which is then properly loaded (for long life) while being able to handle most loads from batteries and inverters under way and for modest periods at anchor.
One of the driving factors is air conditioning. Beyond a certain BTU capacity, big generators become mandatory, using inverters is impractical, and you are now a slave to the AC power of the dock or genset. This forces you to have two gensets as you cannot afford to be without. Now you have those gensets cluttering the engine room. So much weight accumulates that the engine room must go in the middle of the hull. This means your salon is over the machinery space, and staterooms share bulkheads with the machinery. Which is really hard on noise and vibration control.
With our approach, the aforementioned modest genset, ability to service AC needs with inverters (and rarely needing the genset under way) the engine room is more open, and easy to get at gear. It is also in the aft end of the boat, far away from most of the accommodations. One of the reasons we are so quiet under way.
Now to the direct answer to your question about how the systems have been working. Air conditioning gets the job done. In Panama, in May, during the afternoon, the salon is kept at between 78 and 80F - very pleasant. Freezers are kept to about 8F just below the top of the boxes, fridge at 39/40F.
Under way the inverters carry the air conditioning and miscellaneous domestic AC loads. If there is need to run the water maker, one of the air conditioning units is shut down. The only time the genset is used underway is if the air is on and the washing machine and/or drier come into play.
At anchor, the big difference in hot weather is that with air on, and a wash cycle going, their is no capacity left on the 8kW genset for charging the batteries. However, this has not been a problem as there has been a lot of engine time recently! On the FPB 64 we have increased the genset capacity to 12kW so that in hot climates we have plenty of battery charging capacity along with air conditioning.
How is the power consumption going now that you are using an induction cook top on Wind Horse?
We still have the propane stove (did not have time to permanently change to induction and an electric oven) but have been using the induction cook top 95% of the time.
We recently sat for three full days, cooking 100% electrically, and from a full battery bank drew down 640 amp hours (at 24 volts) for all requirements. This includes the usual lighting, fridge and freezers, computers, various AC small appliances, running the air conditioning at night while bathing on dehumidification cycle to keep humidity down, and electric cooking.
We have not measured the cooking loads on their own, except to note that the total amp hours are almost the same as before, so the totals from microwave, toaster, small galley appliances, and induction cook top must be pretty low.
The induction cook top has another advantage in the tropics. It puts a lot less heat into the interior. And in cold weather we are not pumping all the moisture into the interior which is a byproduct of burning propane.
All things considered, this new approach is working really well
My wife is concerned with your comments on air conditioning. She is worried about being too warm in the tropics. is there enough capacity or not?
The simple answer is YES! We have the capacity to keep the interior very pleasant, and humidity levels below 45% in Panama and the Bahamas in May. You cannot ask for much more than that.
Why have you chosen a V-drive and are there any reliability issues to be considered?
The ZF 280V drive we are using is a very muscular unit. Its rating at 2400 RPM is 364 HP. We expect to use an average of 75HP or less at cruising speed, so the transmission is not working very hard.
Most other builders offer a "get home" engine option. How do you handle this?
We've looked at this in detail, even going so far as to design a hydraulically driven prop which would run off the genset. However, like the get home systems of other boats this would work only in smooth water, and we'd not be comfortable using this to finish a long ocean passage. If you consider the risks to your engine, at the top of the list is bad fuel. If fuel has gotten your main engine into trouble, your get home engine is not going to work either.
However, the engine room is being set up so that it would not be difficult to add a standard power take off to the generator and then install the required hydraulic system (there is lots of space for this).
If we did not have a solution to this issue we'd not be crossing oceans in the FPB. But we do have a sail powered "jury rig" that will move the boat which is not dependent on diesel (or an undamaged prop). This is not a fast or efficient sail plan, but it will take you to a downwind destination at up to 100 miles a day, depending on conditions. And it is not fuel dependent. This get home sail system is a part of the standard specification on the FPB 64.
The engine looks like it is tilted at a really steep angle. Is this OK? Do you need special plumbing?
John Deere's specification for the 6068SFM diesel allows a 15 degree head up angle. What is shown in our drawings is 12.5 degrees. This may vary with the final hull shape and prop shaft engineering, but whatever happens we will be within the 15 degree engine specification. A head up angle actually helps if there is an air block in the fresh water side of the cooling system. Otherwise, there are no issues of which we are aware. Note that the pan shown is the standard configuration (our CAD drawings came from John Deere). Plumbing is also standard.
How do you walk around in the engine room and how do you get access to the equipment in the bilges?
We'll have walkways along the aft interior/engine room bulkhead, along the port side of the engine, and then across the back of the engine. These are removable sole panels so that any systems located in the bilges will be easily accessible.
The photos of the engine room on Wind Horse indicate all of her plumbing and electrical down the sides of the hull are exposed. Will the 64 be done the same way, or will you put in covering panels?
Covering panels look nice, but they hide things you should be watching. When something goes wrong behind the panel, you only know when the problem has gotten out of hand. It is also difficult to clean behind the panels. On the other hand, as a builder, you can do a much sloppier job as no one can see what is going on outboard of those panels.
For a boat intended to do many thousands of miles of offshore work this approach - which looks good in a boat show - does not make sense. We want everything exposed, nothing hidden, so if there is a problem we can spot it before it grows. Yes, it forces us to take more care with how systems are installed, because the plumbing and wiring are open to view. But this is the right way to build the boat.
What sort of a prop are you going to use, and how have you arrived at this?
Of all the design questions to do with power and sail, correct propping is the hardest. Even the US Navy, with unlimited budgets, has to cut and try.
We start with the drag characteristics of the hull at various boat speeds, then look at the water flow to various parts of the propeller. This varies with proximity to the hull as the hull drags along a boundary layer of water with it. This water moves at a different speed to the rest of the water hitting the prop - it is slower - so the prop blades have to operate at a higher angle of attack to create the same thrust as when they are free of the boundary layer (which is why we have so much prop tip clearance).
You then look at different types of propeller designs, try combinations of diameter and pitch, and adjust the blade area ratio. Lots of variables!
Our preliminary data indicates a Troost type of blade is best. Presently we are thinking about a 32"/800mm prop, three blades, with a blade area ratio between .5 and .7. These numbers will no doubt be refined as we get closer to sea-trials.
Why are you using a wet engine exhaust?
When we looked at the dry/wet exhaust question for the FPB 83 the decision was easy. We thoroughly reexamined the issue on the FPB64 and came to the same decision, wet is simpler, and offers a host of advantages. Here are the design and user issues involved:
This leaves the issue of the maintenance issues with cooling water supply and the potential for failure during operation. These issues are dealt with as follows:
Bottom line, properly executed (which means the correct alarms, dual intakes and strainer, and good access), raw water cooling is quieter, cleaner, and simpler, without the risks attendant from dry stacks with fire and moisture ingress.
How are dinghies launched and retrieved?
Dinghies are launched using one of the two aft booms. There is a permanently rigged halyard, which leads to the electric self-tailing winch on the after deck. This system, coupled with the fact that the dinks are stored low on the aft deck gives you good control over them as they are being hoisted and moved. If you are caught in a rough anchorage with the dinks in the water and need to put to sea, while lifting the dinghies back on deck the booms can be controlled with their permanently rigged fore and after guys (although these are not normally needed). Finally, having the dinks low like this means you never have to be under the dinghy when it is being handled - a major safety advantage if something goes wrong.
We've read a lot about heavy weather on the website. Can you describe what you would do with the FPB in extreme heavy weather?
There is no specific tactic or golden rule for tactics in dangerous conditions. Every situation is different. Some of the factors to be considered are navigation hazards, wave shape and size, and if there are crossing seas or a new set of waves from a change in wind direction. Another factor is the position relative to the storm center and the storms movement (often moving your position just 30 to 50 miles can make a huge difference in the conditions faced).
With the FPB 64, the ability to run with the waves under control is a huge benefit in some conditions. In others, the maneuverability of the boat helps to keep the bow into the worst of the breaking seas, allowing more active steering tactics.
If you are trying to escape from an oncoming tropical storm, then the usual tactic is going run with the wind on your quarter, in a direction which takes you away from the direction of travel of the storm. At the point at which you can no longer run off because of the risk of losing control, then turning into the seas becomes mandatory. Heading into the waves your speed will need to be adjusted to maximize maneuverability, so you can quickly react to crossing seas which may be breaking.
Although the FPB 64 comes standard with a parachute anchor we do not consider this something to be used for dangerous weather. Rather, it is aboard to help the boat to hold station in the event of a propulsion failure. The GaleRider, which is also supplied, is used as a drogue off the stern. In some situations the GaleRider will allow you to continue running when the boat might otherwise be on the verge of losing control.
It is probably worth mentioning that in all our years at sea, we have never used a drogue or parachute other than to test and practice with them.
Bottom line - between the ability to maintain speed less than ideal conditions, the wonderful stability curve, the ability of the boat to skid with wave impact, and steering control, we think the FPB 64 has the best heavy weather capability of any of our designs - sail or power.Note: for lots more information on heavy weather tactics, and weather in general see our Surviving the Storm and Mariner's Weather Handbook.
The FPB 83 has twin engines. Why are you going with a single engine on the FPB 64?
We would have preferred a single engine installation on the FPB 83. It is more efficient, the centerline prop is better protected from ice and debris, and the engine room layout is much easier with one engine. But the FPB 83 hull shape did not lend itself to a single engine. Obviously the FPB 83 is efficient - averaging 6.7 US gallons/25 liters per hour at 11+ knots speaks to that. But the FPB 64 driveline is even more efficient, and this helps us to maintain a really nice turn of speed (9.5 to 10 knots) while still having a near silent salon/galley area and excellent range, with range comparable to the FPB 83.
What about the maneuverability of the single engine compared to twins?
Although a twin engine installation would be more maneuverable in the 64, the FPB 64 will still be exceptionally easy to handle in tight quarters. The 64 rudder is larger in scale than the 83 (actually, the same area as the 83 on a more easily turned hull). The removal of the keel also helps the FPB 64 turn in less space.
Basically, when turning in a clockwise direction, just using stern torque off the prop and prop wash against the rudder, the FPB 64 will "walk" itself in a circle in not much more distance than its own length. There is a bow thruster fitted, but we don't think this bill be used very often.
I don't understand the photo of the boat aground on a mud-bank. Can you explain this for me?
The FPB 64 is designed so it can be "dried out" on a river or sandbar. The stabilizers are positioned so they touch the bottom at the same time as the hull. The hull structure is strong enough to be happy resting on the bottom. Drying out like this opens up a whole new world of cruising possibilities.
What is the height of the FPB 64 mast and are provision made for hinging it?
The mast is 25.75' (7.9m) from the DWL to the top of the anchor light (excluding antennae). The mast assembly is presently designed to hinge down for storage.
What is the headroom in the FPB 64?
The nominal headroom is 6'6" (2m). This applies down the centerline and along the walkways in the galley/salon and forward cabin. Headroom at the aft end of the starboard aft office is 6'4" (1.95m).
The FPB 83 has hull windows in the forward and aft cabins. Why have you eliminated these in the FPB 64?
There are several parts to this answer. The first is that for the past 25,000 miles the blinds over the hull windows aboard Wind Horse have been closed 98% of the time. In the high latitude summer even with blinds drawn there is too much light coming through the windows for comfortable sleeping (so eye shades are required). In port, or at anchor if there are other boats around, the blinds are also closed for privacy. So, we rarely take advantage of the light which is on the other side of the blinds.
Next, the two boats have different structural systems. The system being used on the FPB 64 allows the hull lining system to go further outboard than on the FPB 83. Even though the maximum beam of the 64 is narrower than the 83, the visual space in the sleeping cabins is greater. If we were to put in hull windows this would reduce the interior space of the FPB 64 by a foot (30cm) due to the structural requirements for the windows.
How do you achieve privacy in the forward cabin.
The FPB 83 has a bifold door which closes off the vertical opening in the steps from the salon to the forward suite. The top is left open for ventilation. If total privacy is desired, a simple removable fabric closure is installed for the period required. This is simple solution which allows a combination of good natural ventilation when it is required, with total privacy when that is paramount.
How do you handle getting rid of galley odors?
In the sole of the flying bridge, under the flying bridge table, is a hatch which is in a natural negative pressure area. With the door to the deck from the interior open (it is typically under positive pressure - the station wagon effect from the house) and the galley hatch cracked, there is excellent natural air exchange. Even in rainy weather these can be left opened as they are both protected.
What do are you doing about mirrors?
In the aft port cabin there is a full length mirror alongside the foot of the bunk. There is a large mirror over the aft vanity. In the forward cabin we have an almost full length mirror behind the aft door to the hanging locker, and then a mirror in the angled face of vanity outboard of the sink.
On our present boat we have no way to get behind furniture to check for systems problems or issues like mold and mildew. What are you doing to make these areas accessible?
Access has always been a prime design requirement, for all of the reasons you mention. The FPB 64 has removable head and hull liners, and the backs of most of the furniture is either open, or has removable panels so that you have good access throughout the interior.
This also applies in the engine room. We have all systems exposed where they can be seen, checked, and kept clean (the norm with a lot of builders is to hide as much of the engine room systems as possible. This looks neat, but in the real world adds enormously to maintenance headaches and the effort you have to go through when you start having maintenance chores.
I am confused by the stability curve and what this means. Can you please explain this for me?
The stability curve is at the heart of the FPB series comfort and its ultimate security - the ability to recover from a capsize. This curve tells us that stability peaks at 60 degrees of heel, then goes almost flat maintaining close to peak stability until 90 degrees of heel, before starting to reduce stability. Stability is lost around 140 degrees of heel. There is then a very small amount of negative stability - the area shown below the horizontal graph line.
What does all of this mean in the real world? First, the further the boat heels, until it reaches 90 degrees, the more stable it becomes and the more energy a wave impact must impart to heel the boat further. The norm with power boats and ships is to peak around 30 degrees, and then begin to lose stability until a capsize occurs at 60 to 70 degrees of heel (from which the boat does not recover). With modern sailboats peak stability typically occurs at 55 to 60 degrees, and then drops precipitously until 120 to 130 degrees where a capsize occurs. If you couple the FPB stability curve which peaks high and then remains high, with its ability to skid with the wave, you can see where these designs have significantly more ability to absorb wave impact with less heel. And in an ultimate scenario, that small amount of area below the line, means very little energy is required to get the boat back right side up.
One thing to note: this is not an actual stability curve for either boat, but a generic representation. There are huge amounts of experience and research involved in choosing the correct curve and we do not want to just give this away to the industry.
Your Wind Horse has a keel. Why does the FPB 64 not have a keel?
The keel on the FPB 83 prototype is there for several reasons. The first is to help hold the boat in place against a beam wind when docking. As the FPB 64 has a deeper hull than the 83 and less house and mast windage, it does not require the keel for holding the boat.
The second reason for the keel is so the boat can be supported before the stabilizers touch the bottom. However, the hull shape and stabilizer position of the 64 are such that the stabilizer fins are even with the bottom of the hull (what we call the canoe body) so that the keel is not required when drying out or gridding the boat.
Removing the keel has several advantages. The rudder is more effective in controlling the boat since the hull can slip rather than pivot on the keel when the rudder is in use. It is much easier to dry the boat out on a grid or leave her resting on a tidal river or sand bank, and we get to reduce wetted surface which is a plus in terms of performance.
I noticed that the bench with the sink and Bar BQ is between the dinghies on the aft deck. Why is it there instead of against the house?
This location has several advantages. First, it breaks up the space of the aft deck so when you are moving from the interior entry door towards the stern you have something to hang onto as you move aft. This is also a good handhold at the base of the steps to the flying bridge, when going up or down. The six man life raft is stored under this structure where it is protected and does not take any additional deck space. Finally, we are working on a design which may also allow for the storage of abandon ship bags in this area.
There does not seem to be a connection between the skeg which protects the propeller and the rudder. Most of the other boats we've looked at have a connection to keep debris out of this area. Why don't you have something and what do you do about lines and other debris?
A question which goes to the heart of our approach to design and our analysis and weighing of risks to the boat. The primary concern is to maintain structural integrity of the steering system. The greatest risk to this is in a grounding. Which is why our standards include a rudder structure designed to twice the ABS rudder requirements. The rudder shaft stops about half way down the blade and then the bottom plate is made of lighter material. What we are aiming for here is a frangible structure where the rudder tip deflects before the rudder shaft is bent.
Now, imagine yourself sitting on a reef, with the bow supported and a rock directly under the connection between prop skeg and rudder. Huge loads are being applied to a relatively weak member. The common result is for this connection piece to deflect up and jam the rudder. You have then just lost your steering.
What we are saying here is that we consider the risk of jamming the rudder with a bent skeg extension to be unacceptable compared to the risk of picking up something on leading edge of the rudder.
How does this work in the real world? We've been fitting exposed spade rudders for a long time. We have had many of our boats hit reefs and go aground, and lots of rudder tips damaged, but we are not aware of a single instance where the boat could not be steered once pulled (or floated) off the reef. In our own experience, including lots of cruising in Maine (line catching capital of the universe) we have caught exactly one line on the rudder.
There are a couple more things in play here. One is that the rudder and both stabilizers have a line/weed deflector welded to the hull ahead of the foil. This reduces the chance of catching something between hull and foil.
Next, the FPBs are fitted with line cutters on their prop shafts.
I've noted lots of comment about motion at sea with your designs. I have also seen some of the write ups (I think it was Passage Maker magazine) where the editor said the motion was the best he'd ever experienced. If The 83 is so successful, how do you know the FPB 64 will work?
There are various numeric ways of modeling motion. With the 83, in addition to our intuition, based on lots of experience with canoe body style hulls, we had Oceanic Consulting do extensive CFD analysis for us. The CFD work was employed to see if anything came up which our experience had missed. The CFD analysis confirmed our own intuitive and numeric projections.
Now that we have had a chance to study the 83 in the water, we have a much better feel for what makes her such a comfortable vessel offshore. This is based on 25,000 miles of real world experience, much of it spent going uphill in less than ideal conditions.
During these many miles we've watched how the boat reacts to various wave shapes - regular and confused, steep and long period, with square backs and more gentle shapes.
At the same time we have been thinking about how to refine what we have with the 83 into a smaller package - not easy, which is why it took us two years of study to come up with the 64.
Once a weight budget was established for the 64, we started drawing different types of hulls. The distribution of volume is based on the speed you want to optimize for, steering control down hill, and how the boat reacts to head and beam seas. You get one aspect just right, but the others are then often not where you want them to be.
So you try another shape, squeezing volume in here, taking it out there.
We are presently on hull family number 59 (there are an average of 20 variations on each family), and we really like what we have.
There are the usual numeric models to check. But the most important part in this process is gut feel. Looking at the hull, and then thinking about how it will react in various types of waves. If we did not have the experience with the FPB 83 prototype, this would be a much more difficult process. But the fact is we know in intimate detail how Wind Horse reacts to all sorts of conditions. Which gives us a wonderful foundation against which to judge the FPB 64.
Did we mention we really like this hull shape?
have been following your Wind Horse evolution from almost the beginning
and I am happy to see the possibility of a smaller version but I have
a question that relates to ultimate stability of the FPB64.
Stability is a function of:
Creating the ultimate stability of the FPB 64 is a careful balance of these elements. Equally important is the shape of the stability curve and the way thus affects the ability of the boat to absorb wave impact (so you do not need the ultimate stability) and so that the boat is comfortable in normal conditions.
The above is not easy to get right, which is why we spent two years working towards the FPB 64 design after successful sea-trials on the FPB 83 Wind Horse.
One other issue which has to be considered is the water tight integrity of the structure which provides the buoyancy. If this is breached, then your stability curve is quickly compromised. Which is why the windows are 19mm (three quarters of an inch thick).
How are the stabilizers compartments sealed?
Stabilizer mechanisms are totally contained within coffer dams. These are located in the basement, under the salon. Each compartment has a water tight hinged lid for security and ease of access. We should add that the structure itself within the coffer dam is substantial and designed to spread the load of the stabilizer fins.
What about the hydraulic and bilge pumps hoses into the stabilizer compartment?
The stabilizer hydraulic hoses run through special glands, similar to what are used for water tight bulkheads. The bilge pump hoses connect via a pipe welded to the top of the compartment. There is also wiring for the stabilizer and bilge pump water level sensors which passes through special glands.
Can you give me some more information on the rub rail? Why are you using this heavy looking aluminum?
The rub rail is a custom extrusion which is designed to do a variety of things. It provides the landing for life line stanchions, forms the toe rail at the edge of the deck, and works to hold the topsides clear of pilings when you are tied to piers.
This rub rail extrusion is much stronger than it needs to be for any of the above requirements. The reason we make it so much stronger is to help to reinforce the deck edge in the event of a collision. If another boat drags down on you or hits you, if they come into contact with the rub rail the extra strong extrusion spreads the impact load across a wide area of hull to deck joint.
Why are you using such heavy 15/32" (12mm) bottom plate if the Lloyds Special Service rule only requires 8mm?
The Lloyds rule is conservative, and the 9mm / 5/16" plate is very tough. For the ocean loads and most debris, this is more than enough. However, we can afford the weight of the heavier plate, and it gives us a much higher factor of safety against risks like containers, and point loadings when aground. It also is emotionally comforting to know we have such a tough (not to mention good looking) bottom.
What is the reason for the unfinished aluminum hull?
You can always paint the hull, but leaving it bare has several advantages. First, you don't have to worry about scratches from other boats or kissing docks. Second, there are docking situations where it is difficult to keep fenders in place, or you may be using a spring line to get off a dock and the hull is against the vertical surface of the dock. Again, no worries. The third reason, for us, is the most important. We like the combination of a workboat-like appearance on the outside coupled with a drop dead gorgeous interior. Guests coming aboard simply do not expect what they find when they step below.
The bare metal finish stays shiny for about six months, then begins to dull a bit. This is a form of natural oxidizing on the surface of the aluminum. Once the natural film is established you have no maintenance. If you grow tired of the mat finish, a couple of men in a week can have the topsides shiny, Or, you can paint the topsides. But we suggest giving the bare finish a season of cruising before deciding. It doesn't take long to fall in love with it.
Can you fill me in on the steering system design?
Of all the critical systems on the boat, steering is the most critical. Almost anything else can go wrong and you can deal with it, but if steering is lost, especially in heavy weather, the situation can quickly deteriorate.
The details on the FPB 64 are similar to what has worked so well over the years with our other designs. Take the rudder structure. This is designed to twice the American Bureau of Shipping requirements. There is a solid rudder shaft half way down the rudder, and then a spar the rest of the way. The engineering target is that if the rudder is damaged in a grounding, the bottom of the rudder gives way before the rudder shaft is bent. The rudder shaft penetrates the hull through a heavily reinforced area of the hull, using a welded pipe which carries the bottom bearing. This pipe comes above the waterline, and attaches to a hose which runs up the rudder shaft. There are no stuffing boxes for the rudder shaft which can be damaged or leak.
At the top of the rudder is a tiller to which hydraulic cylinders are attached. This tiller is keyed to the rudder stock, and is of solid structure.
There are two totally independent hydraulic steering cylinders, each with its own pump system.
Finally, there is a proper emergency tiller with relieving tackles.
How are you dealing with insulation and condensation?
Within the living area, the tank tops, hull sides, and deck are covered with a closed cell insulating material called Armaflex. This has excellent insulating and noise control properties, and has the lowest moisture absorption of any insulating foam of which we are aware. The structural members, like longitudinals care covered with 6mm (1/4") material while the broader areas have 12mm (1/2") material. We have found that condensation is minimal on the FPB 83 in Alaska during late spring with cold air and colder water. And of course, the insulation contributes to a boat that's extremely quiet.
What provisions have you made for solar or wind power on the after deck? Will there be sockets available as on Wind Horse?
There will be a pair of two inch (50mm) pipe sockets all the way aft on the corners of the stern. These can then be used for either solar or wind mill support points.
Have you thought about using double glazed windows for insulation and condensation control?
We would love to use windows with a thermal break between inside and outside panes. However, we have not been able to find any strong enough for our needs. Keep in mind that we are using 19mm (3/4") marine safety glass for most of the windows. So, the bottom line is that we have not found a suitable alternative. On the other hand, as previously discussed, condensation has not been a problem. So, we are left with thermal load. We deal with this by using high quality infra red radiation blocking film and easy to set side awnings. And for cold, the 67,000 BTU heater can deal with the heat load, down at least to freezing.
We just read the June issue of Passage Maker magazine. We loved your article on getting "off the beaten path." That is exactly the way we want to cruise. In the magazine Nordhavn has an ad touting the benefits of their fiberglass construction, and in the process they imply that metal is not as good. How do you answer this?
The answer is complex and depends entirely on what is important to you and how you want to use your boat. We have designed and built many yachts of both fiberglass and aluminum. Each material has its advantages.
It is certainly possible to make a plastic hull as tough as a metal hull for most types of loads. We have been doing this for years. However, to create toughness in a laminate that compares to aluminum you need very carefully engineered and manufactured laminates. The reinforcing matrix has to be done just right, with correct fiber orientation and resin to glass ratios. For example, you can have a very thick laminate made up of matt and woven roving, held together with polyester resin which is inferior to on a fraction of its thickness which is built from higher strength ingredients. Thickness itself does not necessarily create a tough structure.
Fiberglass has a couple of advantages. It is certainly less costly to produce, and it does have a nice finish (until UV radiation takes its toll inn old age).
But aluminum has its own mix of advantages. The first is that properly done, there is nothing to leak. Hatch bases are welded to coamings, door frames are welded, stanchion bases are welded, and deck hardware is either welded or blind fastened.
Next, properly designed and executed, aluminum creates a double bottom which is important for security, and for tank capacity. This is why the FPB 64 can fit in all that fuel and water. If she were built of fiberglass, and we considered briefly this option, tankage would be a lot less and she would not have a double bottom.
Then you come to the issue of shiny topsides. If you are headed from marina to marina, and like the "yacht look", then you are going to appreciate either a painted aluminum hull or fiberglass and its gelcoat. But if you are "off the beaten path" lying against rough docks and pilings, hanging out with work boats on occasion, bare aluminum is going to be a wonderful bonus. It is also lower key, fits in better in some of the more rewarding cruising destinations.
There are a host of other advantages to a properly executed metal yacht which are covered in detail in our Offshore Cruising Encyclopedia.
For years many folks have assumed aluminum was noisy based on early experience with uninsulated metal boats. However, a properly insulated aluminum hull is significantly quieter than a fiberglass counterpart. This is the case with both machinery noise and ambient sound from wind and waves. The reason is quite simple. Fiberglass presents a uniform, hard surface, which is ideal for resonating and bouncing noise. Aluminum, if properly insulated, is just the opposite. The hard aluminum surfaces are covered with a sound attenuating (and insulating) material.
Which brings us to heat, cold, and condensation. You can always deal with heat and cold by adding or subtracting BTUs. But condensation of the hull in cold water is a special problem. A thermal barrier sufficient to prevent condensation is required. Typical fiberglass laminates, even those with thick cores, do not have sufficient insulation value to prevent condensation. So these hulls sweat. Moisture sitting on the hull surface eventually grows mold and mildew. Properly engineering and construction of aluminum offers several big advantages. First, bilges are eliminated within the living area as immediately below the cabin soles lie tank tops. Second, hull and related structural surfaces are insulated.
Now the question of longevity. We feel that given proper construction and maintenance, both aluminum and fiberglass are long lived. We launched our first aluminum yacht in 1981. That is now 27 years ago and she is still going strong. The same can be said for the fiberglass yachts we built in that era. We see no significant difference in the longevity of the materials.
A final word on materials. For our own yachts we obviously have the option of either material. When we started the design of Wind Horse, the FPB prototype, we did a complete structural analysis and design in fiberglass, investigating a variety of high and medium tech laminate schedules in the process. That we chose aluminum in the end is based on tankage, better resistance to abrasion in ice and groundings, the fact that it is much quieter, and because we like the low key look. We prefer the combination of high tech work boat appearance on the outside, and lovely yacht interior (which remains hidden to the unknowing) on the inside.
How much time do we have to allow once we pick up the boat to get ready to go cruising? We've had two friends who purchased new boats and it took them at least six frustrating months of work and preparation.
Your question goes to the heart of our approach with the FPB 64. The specification is for a complete boat, right down to life raft, an excellent suite of electronics, a full set of spares for cruising in out of the way locations, and all the systems and back ups we have on our own boats. There are no options, and the boat is ready to go cruising when sea-trials are completed.
This means that from your standpoint you have to learn about handling the boat, become familiar with the systems, load your personal gear, and take off. The commissioning process is done during sea trials. So you are ready to go as soon as you are comfortable with your knowledge of the boat.
That this takes place in New Zealand is a huge advantage. Within a day's cruise of where the boat is built you have the Bay of Islands to the North and Haurakai Gulf which fronts Auckland to the South; some of the best cruising in the South Pacific. These are great areas in which to learn about the boat with technical help always close by.
Bottom line, we would expect most clients to spend a couple of months using their boats before they felt ready to head off on their own.
I have studied your material carefully, and looked at the specifications, It does not seem possible that you could build to such a high specification, in aluminum, at the price for which you are offering these boats. How is this possible, and what, if anything is being left out?
A perceptive analysis... The key to building such a high quality cruising design like this is construction efficiency. We start with a 3D "model" of the boat which is the basis for the metal work and for the interior. There is a substantial front end investment in the engineering, but when this is done, both the metal work and interior fabrication begins with computer controlled cutters. This reduces or eliminates tolerances which makes assembly more efficient and faster.
The next part of the equation is specifying a complete boat, without the need for options - everything you need for an ultimate cruising machine is specified from the beginning. This means the boats are sisterships and significantly more efficient to build in terms of man hours and time - the build team can complete more boats in less time. Both factors reduce costs.
Finally, everyone involved in this process runs a lean business, without frills.
Bottom line - the majority of the purchase price goes into the boat. If this were a one off project the cost would be double. If we had "options" it would slow the process to the point where we'd have to charge 25% more for each boat just to cover indirect costs. We think it is much better to deliver a complete boat, right down to spares, making the process for the builder and you more efficient.
I understand the initial four boats are now committed. What are your plans for subsequent boats?
We've been gratified at how fast things have moved on the sales end. It appears as if we are not the only ones who like this boat! We are working now with the builder on how to deal with a second round of boats and should be in a position to begin to accept additional deposits shortly.
I have just read the recent stories on your haul out. Can you review for me the changes you have made to Wind Horse?
The changes to Wind Horse have been few the last three years. These include:
That's it. Not much considering we like to tinker and fine tune. All of these "lessons" learned have been incorporated into the FPB 64