Blue Horizons 30

BH30 Profile

 Blue Horizons 30 is a twin keel ultimate voyaging yacht with Chinese rig.  A twin keel boat is easy to beach for routine bottom painting and other work.  The slightly shoaler keels of 4'6" draft are just right for shallow areas like parts of the Bahamas, the Keys, and the Chesapeake, plus a great many other places throughout the world.  Twin keels are exceptionally good to windward in moderate to heavy winds.

With 10'0" beam and a nearly flush deck we can get an enormous amount of room into the interior.  This particular type, though the nominal displacement to length ratio is in the lower range for serious liveaboard voyaging yachts, can accept a wide range of loads without a performance penalty.  Twin keels work well offshore because the unusual dynamic characteristics will give her a level of comfort normally associated with heavy long keel vessels.  This starts with the fact that twin keel vessels with skeg hung rudders tend to be steadier on the helm than fin keel spade rudder coastal cruisers, therefore much less tiring to hand steer if necessary, and much easier to handle well with a simple robust wind vane steerer.

Further the increased roll moment of inertia of twin keels reduces roll considerably through two factors.  The first is the concentration of ballast relatively low in the relatively long total length of keel bottom which slows the roll through a generous vertical arm.  The second factor divides the ballast into two pieces, well separated from each other laterally, thus also increasing the roll moment of inertia.  All this, combined with the twin keeler's tendency to entrain a large mass of water with the vessel when rolling, gives both enormous resistance to rolling and very quick damping of any roll which does develop.  Blue Horizons 30 will be unusually comfortable at sea, and in harbor, or in coastal cruising, powerboat wakes will be much less offensive as it is harder to start the boat rolling and the rolling damps down very quickly.

In many very crowded harbors there are large areas where no boats anchor or moor because these areas are shallow at low tide.  A boat like this will be able to anchor there and have plenty of swinging room.

Another advantage lies in the ability, if desired, to put a twin keel yacht on the deck of a larger vessel or special purpose yacht transport vessel.  This can allow someone pressed for time or with health problems to get their vessel to a new cruising ground more easily.

These days the increased number of experienced voyagers has brought more support for a pilot house with all controls and sail handling led to it.  These days it is widely understood that living aboard and long term cruising and voyaging is different from holiday cruises.  Being able to stay out of wind, rain, spray, cold, hot sun, etc. reduces fatigue a great deal.  The crew tends to end up spending a great deal of time in the pilothouse.

Blue Horizons 30 has plenty of height under the side decks for generous sitting headroom, with the ports in a contrasting wale in the topsides.  Though almost flush decked there is a low trunk without ports to give generous headroom without excessive topsides height.  There is plenty of room on the top of the pilothouse and this low trunk to have plenty of solar panels, and still have space for a three piece sailing dinghy just aft of the mast.

This vessel is a perfect size for a couple or small family to liveaboard.  People you will meet who have been living aboard for less than a year seem to be setting out on boats averaging in the neighborhood of 40+ feet.  However, if you poll only people who've been living aboard and voyaging for more than a year you've already dropped to 35 feet average length.  If you look at people who've been living this life for more than three years the average size is just a hair under 30'.

Another point is that by eliminating the sunken cockpit in favor of deck box seating we add another cabin below and have the interior of a much larger vessel.  You also have a safer vessel in that the cockpit doesn't hold a huge weight of water anymore if a wave goes over the boat and you eliminate the major cause of broken bones on yachts, which is falling into the cockpit.  A great many people have eliminated cockpits on their boats in favor of deck box seating.  Many experienced sailors have chosen designs of ours partly for that reason.

The particulars are as follows, but remember that displacement will vary a bit with loading:
Length on Deck            30'
Length on Waterline      25'
Beam                           10'0"
Draft                            4'6" (varies with loading)
Displacement               10,500 pounds
D/L Ratio                    300
Scantlings Numeral      5.47 (cube root of displacment in cubic feet)
Ballast Percentage       40% (approximate)
Ballast                        4,200 lbs of lead
Prismatic Coeff.          .56
Sail Area                    585 square feet

The lines are very carefully faired for best flow and the rudder skeg and keel roots are carefully faired to eleminate humps and hollows in the water flow as far as possible.  Using a skeg hung rudder makes it much harder for the rudder to be stalled in adverse conditions.  As an outboard rudder it is more easily repaired on a beach if necessary, though this skeg and rudder combination and the windvane are made as robust as possible and are hopefully nearly invulnerable to damage.

The combination of the moderate length twin keels and the substantial skeg hung rudder result in a vessel steady on the helm and easily controlled by a windvane even in heavy weather.

The outboard rudder allows a simple, robust trim tab type wind vane steerer, which can be adjusted from the pilot house when desired.  This allows the watch at sea to sit comfortably in a pilot house armchair and just keep a lookout.  This avoids fatigue and can make ocean crossings and periods of inclement weather much more enjoyable.

The single Chinese sail allows plenty of sail area in a rig that is self-tending in tacking and can be hoisted, lowered, reefed and unreefed entirely from the pilot house.  The rig has been deliberately designed to be easy for small or older people to handle.  The ease of reefing and unreefing allows having the optimum sail area up a much greater percentage of the time.  The mast can be either solid laminated wood or a very light hollow carbon fiber mast.  These days with the cost about the same most will go for the carbon fiber spars.  The rig is arranged so that the spar can be pulled using gear on board if you find you wish to enter a canal system with low bridges.

The safety advantage of an unstayed rig from a structural point of view is in the reduced number of possible failure points.  You have only one design problem:  Is the mast strong enough to carry the load with enough safety factor so that it will never be loaded enough to fatigue.

Over and over our clients, for whom we have designed Chinese rig vessels optimized for living aboard and ocean voyaging, have told us that they were surprised to find that they were able to beat the pants off of many boats of similar size and even quite a few larger ones, even to windward.  We discuss why in detail in the Study Plans but the jist of it is that the upper part of the sail uses a different type of lift than the theoretical "foil" lift we are used to thinking about.  This is called "vortex lift" and has only been recognized in both yacht and aircraft design quite recently and has still not really reached the level of public understanding.

For construction we have used the highly efficient "sheathed strip" construction in which the hull and deck are built using longitudinal square section strips, sheathed transversely inside and out to give a very strong for the weight and very damage resistant construction.  In addition the entire vessel has been lofted in the computer so that the plans can include dimensioned patterns or CNC files for virtually every major part of the vessel.  These days your supplier can precut a building jig, interior joiner work parts, etc., so that whether built by an amateur or a professional will basically amount to assembling a kit.   While we discuss this extensively in the Study Plans text, surfice it to say for now that custom built boats like this are these days no more expensive than a comparable quality stock boat.  That is if you could find a comparable quality stock boat.  Since this also cuts out the huge ad budgets that a stock boat builder must shell out to keep selling essentially the same boat over and over, it is quite likely that the custom vessel may end up actually costing significantly less.

While there is a long section in the Study Plans on the accommodations, we will content ourselves here with simply adding a plan view showing everything in as artistic a manner as we can.  It should give you a decent idea of the general arrangement, though not a lot on the details:

BH30 Accommodations


About the only bit of the accommodations which you probably can't sort out easily is the bit forward of the mast in the forward cabin and aft of the double chain locker.  This is a nice comfortable sit up bath.

Though you could use a standard small diesel quite easily, what the drawings actually show under the pilothouse sole between the two arm chairs is an electric propulsion unit and batteries.  Since the auxiliary is used in calms, getting in and out of harbors, and in canal systems, it is quite easy to charge the batteries entirely from the solar panels.  To summarize a very long section on the electric propulsion we can get quite close to hull speed as a maximum from quite a modest electrical motor. If we drop back the speed just a bit from that into a speed range that an ocean crossing power yacht would use the range becomes quite large.

These days everyone has a list of electronics which the magazines make sound quite necessary.  We would very strongly urge having the absolute minimum you can persuade yourself to buy at first.  Probably a handheld GPS or a small chartplotter, a handheld VHF for emergencies and weather forecasts, and perhaps a depth sounder.  Beyond this make a list of what you think you want and keep it in your manuals binder.  Whenever it occurs to you that you'd really like to have one of these items, put the date next to it on the list.  After a year of living aboard and traveling review the list.  It will be amazing how few items have even one date after them.  If you find an item that you repeatedly put a date beside, that's the one to get.  The more you add the more of your time you spend just trying to keep everything working.  As our friend Kent says, "The Caribbean is full of 40' plus boats with one guy on board who says that his wife will come back when he gets everything working."

Our personal voyaging days are, sadly, over.  We're just too creaky.  Don't wait.  Get going now.

Blue Horizons 30 Study Plans, $66: 

Blue Horizons 30 Complete Plans, Fully Lofted, $3,706: 
Blue Horizons 30 Complete Plans, Without Lofting, $2,022: