Asheville is the author's home town
 Carol and Hans van Krieken |
Hans an Krieken, in his younger years, on his boat "Bacchus" |
Listed below Are Articles by Hans van Krieken
On the subjects of religion and spirituality:
On the subject of politics:
On the subject of investing is horse race bets:
On the subject of boat design:
http://www.becaughtorbeketched.com/design_objectives_summary.htm http://www.becaughtorbeketched.com/from_article_directories.htm |
http://www.becaughtorbeketched.com/design_objectives.htm |
Revolutionary super fast, super shallow, inter-ocean surfing hull design
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I designed this super shallow, super-fast hull in 2006 and in 2007 applied for US patent. I was in quandary whether to advertise this hull as the patent is only good in the US. Therefore I have never advertised this hull design. However, I am getting older (72 years old this March) so I decided to either try to have a magazine publish an article on this hull or to advertise this hull in conjunction with an an article like this.
I designed this super shallow, super fast, radical hull at DWL 50 ft; the optimum length to surf the hull on large ocean swells and also as a cruising sailboat. This cruising hull can surf across an ocean, plane while going to windward and can sail steeper into the wind than any other vessel. As you can see from the picture above this hull has no keel, no permanent ballast and no conventional rudder. The hull will perform as a surfing platform, sailing platform and motor vessel.
The super shallow, super fast hull design lends itself to sailing craft to about 300 ft, motor vessels up to 500 ft for both inland and coastal use. As a surfing platform it can be designed in lengths of 25 ft to about 85 ft. As a surfing vessel it must comfortably fit on the forward slope of the swells it is designed to ride. The skin of the bottom of the hull shown in the accompanying figure can be fabricated using conventional methods using monel or copper-clad steel, aluminum or conceivably fiberglass. The reason for such materials is that the bottom must always be as smooth and clean as possible in order to get all the speed producing innovations to work right. Patent for this super shallow, super fast hull design and for copper cladding the bottom are pending.
The hull will go over 50 knots at
sustained speeds with sufficient wind and/or trade wind like swells.
This particular hull design (LWL of 50 ft) is 18 ft wide at the turn of
the bows into the sides and the beam continues to increase from the bows
at about a 4o angle with respect to the centerline to reach a
beam of about 21 ft at the stern. The bottom is flat. The hull has no
keel, no permanent internal ballast, and it has no conventional rudder. The hull design shown is 59 ft LOA. The flat bottom incorporates two steering and course stabilizing rotors on which sets of fins are mounted. These rotors are in lieu of a rudder. They are also used while planing or surfing the hull. I have some preliminary ideas and designs to raise or hinge some of the fins on the rotor to reduce wetted surface at high speed. Any one rotor also serves as spare rudder in case the other malfunctions. The bows sections and the intersections of the bottom with the sides are equipped with multiple sets of pressurized air nozzles and the hull is equipped with multiple sets of crosswise venturi slots that suck air under the hull in great quantities as the hull speed increases above 10 knots. The venturi arrays have much more sophistication to them but I can leave that discussion out of this epistle. The air nozzles are needed to quickly bring the hull to planing speed. It must quickly crawl out of the water into planning attitude so a lot of air is needed to get her up to speed and planing fast. The onboard air tanks could be charged by manpower grinding away before start and during a race or be charged by the propulsion motors. The venturi air flow can be controlled by a damper valve so that the boat can be slowed down and not slide into the trough in front of the wave on which it is surfing. The stern is equipped with three large trim surfaces to help keep the stern configuration above the water at high speed to prevent wake turbulence while plaining or surfing. Along the straight flat sides (having 3.5o tumble home) are sets of water ballast scopes that are filled with water from the lee side just before the boat tacks so that the ballast water taken in ends up on the high side after the tacking maneuver has been completed. In this manner between 0 and 10,000 lbs can be taken on board as is needed according to the wind force and sails flown. Just before the next tack is negotiated this water is dumped and water again taken on at the lee side just before the boat tacks again. This disposable ballast weight is the equivalent of having up to 50 people sitting on the high rail. Idle crew members can also ride on the high rail. The wide-beamed and very stable boat thus can carry enormous amounts of sail and still retain a minimum heeling angle. The idea is to keep the boat as level as possible to trap the air under the hull as long as possible. A 5o heel should be the maximum allowed. The sides have a 4o angle with the centerline of the hull; so that the lee side becomes keel when she heels. When the boat sails on the wind the boat is thus moving upwind at an increased angle of 4o. Steering is done by rotors. Two rotors are used; one up front and one near the stern. The helmsman only has to turn the rotors about half the angle of a conventional rudder. The great advantage of these rotors is that one can turn both rotors upwind while tacking into the wind causing the boat to crab or crawl upwind while yet retaining full efficiency of the sails. The water ballast tanks are also important in trimming the hull while surfing. The stern should be a little deeper in the water for good steering stability. While surfing large ocean swells the stern rotor is locked into mid position to serve as a course stabilizer while the front rotor and/or the outer trim surfaces at the stern can be used to control the heading angle with respect to the swell. There are a number of other innovations in this super shallow, super fast hull design that control heel and speed, such as a speed brake. The design has 6 retractable legs so one can work under the hull between flood tides or park it to reconnoiter the beach. The hull can be beached for excursions without anyone getting wet. The advantages are innumerable. The next great feature is that this hull can climb onto the front of a swell and ride it all across the ocean in the trade wind sections of the world or at the fringes of heavy storms, and then it is making between 45 to 55 knots over long stretches. Since this hull can surf any time during bad weather there is never a chance of it capsizing. It is always under full control while riding with the brute force of wind and swells.
In mono-hull design it is in a class by itself.
This super shallow, super fast hull design was derived from my
42 ft cruising hull design. I had a 1/8 scale radio-controlled
model made of this 42 ft LOA, cruising boat that has
forward and stern rudders. That hull did go to windward as
anticipated; although it
is a very difficult task to perform with a radio-controlled sailing
model. I knew that I had to get rid of the keel to make the dual
rudder configuration work more effectively. That is why I ended up
designing a super shallow hull with no rudders, but instead
with two rotor, a flat bottom and no permanent ballast.
Below find shots of that radio-controlled model. The jib has a flexible plastic tube in the seam of the foot that works very well. That design gave me the idea for the super-shallow, super-fast design. The rudders in the line drawing are painted blue for easy identification.
The super shallow, super fast hull is really too complex a design to test
satisfactorily as a model. If a model was to be made it has to be at
least a 1/3 scale so that a person can actually sit in it and
manually operate it. I just do not have the financial support to
pursue a model test for this one. I am, however quite confident that
this hull performs as I say it will. Below are some pictures of the
cruising hull model and its rudders.
The model shown, by the way, is for sale as is ($18K US +S & H); so are the design plans for the full scale hull ($6K US). |
This roomy cruising hull and its 50.5 ft sister are the best. I know that this design can and will sail around the world easily five times in a thirty years period and will keep its owners happy as a lark living on it. It is the best there is because it is designed according to the best scantling standards using the best of woods; indeed it is the best because it is designed in wood. However, when the hull is built upside down, a mold can be easily drawn from it and a hundred plastic tubs drawn from it as has been done to create the model. See www.becaughtorbeketched.c om
Carol, also, composed a book. It is the neatest and handiest book in my possession. It is called "Usernames & Passwords At Hand". I could not live without this handy book anymore. Get yourself a copy at www.usernames-and-passwords-book . com. I like the soft-cover version the best.
Hans or Carol can be reached at 828-676-0832.
Created 1-1-2009, Revised 05-21-2009