20 Apr 2012


Sailing Faster & Staying Overnight

Design contests are fun.
I remember three sailboat design contests since I started out professionally in 1991.
* One was in Yachting World 1995
* One in Yachting Monthly 2000
* And last year this oneDesign Challenge III, in Professional BoatBuilder together with its sister publication WoodenBoat.

The theme for this contest seemed interesting and, as it happened, I had had a boat in mind which was very much in line with the ideas behind the competition. Still, we were busy with other work and with only a few weeks to go before the closing date, we sat down to put this new design on paper.  

The Baby Celeste
picture by Christian Wallgren

There is something about certain boats, like they seem to talk to you. You see a sailboat moving slowly in the morning breeze, yanking her mooring lines a little, anxious to get out on the bay. And you feel this urge to join her, to hop onboard and cast off.

Fast, responsive, simple, immensely fun and very versatile – this must be tempting for many people. Young couples, sailors with little time, people in the cities, Wednesday night racers. Or sailors who have already had a serious cruising yacht which took an hour to get underway, despite a couple of extra hands onboard.

For some time, I have had this vision of an utterly modern, responsive sportsboat with a big, inviting cockpit for long summer days. But, no matter how fun this boat would be to sail, she would only be half if she didn’t have a cosy little shelter, some basic comfort and a good, warm and dry berth inviting you to stay overnight. A little boat for those among us who still appreciate the basic joys of life.

WoodenBoat’s and Professional BoatBuilder’s Design Challenge strikes a very keen note for a seasoned sailor. There may also be a commercial potential in this kind of boat; indeed, this is just one more reason that I find the thought of it rather thrilling. So much that I decided to enter a design competition after having managed to stay away from them for 12½ years.

The Baby Celeste may be a slightly different interpretation of the ideas behind the Design Challenge. I decided to pack her into a somewhat traditional folklore ballad kind of composition. Too conventional perhaps? Maybe, but she is still very unusual, there is nothing like her on the market, is there? Too complex? Well, she is still a very simple boat… Too basic? For some, absolutely, because her comfort is rather primitive, there is no shower, no standing headroom. She certainly is not for everybody.

Some details of the design may need a comment:

Hull concept

Under water, the Baby Celeste has a sharper bow than almost any boat of similar proportions. Her waterline entry angle is a mere 10 degrees. This makes her able to slice through waves at speed, and with great ease.
But the most outstanding feature of this design must surely be her length / beam ratio, in particular at the waterline, at a whooping 5,4. Why not make a shorter, planing hull? This is all about high average speeds. The  Baby Celeste  will be extremely swift on all points of sailing, not just downwind. She will have a smooth transition to speeds higher than hull speed and thus will be equally happy at 6½ knots on the wind as she will at 12 knots on a reach.
The downside to this hull shape is stability of form, and she will depend on her deep T- keel for stability. A beamy boat of the same length would have had greater wetted surface, required more sail, would need heavier scantlings because both hull and deck panels are bigger. Such a boat would, effectively, have been a much bigger boat. 

Keel arrangement
The keel can be lifted for trailering, or for motoring into shallow anchorages.
The lifting keel is mounted in a carefully cast square shaped moulding which is fixed to the hull and deck, with the adjoining main bulkhead completing the box-like, self supporting structure. This arrangement gives excellent strength and stiffness to the part of the boat which carries the greatest loads, and eliminates the need for further stiffeners or structural members.
To improve things a little further, as can be seen in the drawings, there are also elastic sliders mounted onto bumpers at the corners of the square top of the keel. This will both ensure that the keel is hoisted without much friction, and allow it to move a little at impact. Even a slight movement will reduce the energy to a fraction, possibly eliminating the risk of damage completely, if for example one hits a rock.
The keel is hoisted by means of an 8:1 tackle with blocks either side of the top of the keel case. The line is lead via a jammer to a dedicated winch and cleat. The rudder kicks up as well and can be controlled via a lever through the rudder head.


The chainplates are near the deck edge, anchored in the main bulkhead, giving the mast a wide base for the shrouds. This allows for a thin and light mast section, and for single spreaders to be used. Aluminium spars.
The mast step has a hinge at the back side, like a tabernacle, so the mast can be set up on the boat. When doing so, it is held in place by the (rather common) arrangement consisting of two removable stanchions holding the lower shrouds. Lifting is done by means of the jib halyard, boomed out at the mast step. Once the spar is in place, the upper shrouds are set, the stanchions are removed, the lowers are lengthened and attached to their turnbuckles.
Sail handling is straightforward. The mainsheet is on a padeye in the cockpit floor. The jib is on a furler, sheeted to a ‘Hoyt’-type boom which makes it exceedingly efficient on a reach. The jibsheets lead aft each side under the cosmetic roof. On the aft face of the cabin there is a group of clutches recessed on each side; these are not shown in the drawings. A gennaker can be flown from the bow.
The  Baby Celeste is a very fast, very responsive and rather tender boat and will be at her best in summer winds. For crossing the Channel in September, one should look for another kind of boat. But with her easily driven hull shape, she will offer a civilised ride home in a blow, under a very deep reef.

The Baby Celeste has watertight compartments forward and aft, meaning that there are no deck hatches. However, there is one in the port cockpit seat, for dry storage like sails and cushions, and one in the cockpit floor, for things like an outboard.
And of course there is a hatch in the foredeck, offering light and air to the berth below.
Installations forward, like the bearings for the jib boom, can be accessed through a hatch set in the forward watertight bulkhead.
picture by Christian Wallgren
Depending on where you measure, the cockpit is 3,15 – 3,60 metres (10-12 feet) long and laid out for 1-6 persons. Surrounding the cockpit, there is a low pushpit onto which is attached comfortable backrests for the sofas, modern daysailer style. The helmsman sits aft, or on the sofa. The sofas are long enough to sleep on in fine weather and a fine place to sit in port. There is room for a small table in the middle.
The transom is open for easy access from a dock or dinghy, for swimming, and for the simplest possible rigging of an outboard. Still, a little electric engine and a folding propeller is a nice option.
Such a propulsion system is completely silent, clean and odourless, and is at your service at the touch of the control lever. It reaches full thrust, 60 kgs (130 lbs), in less than two revolutions. One of the beauties of the propulsion system is that, because it is electric, it allows the incorporation of other electric creature comforts. The system is ‘refuelled’ by plugging in the cord. It can be kept topped up by a sun panel.
The clue to this system’s efficiency is in the speed control, the refrigeration technology and the optimising and careful integration of the components. The system is provided by Oz Marine in Sweden; on other markets there may be other suppliers of similar systems although I believe their fridge is a very remarkable thing.
Nobody needs to be on deck unless you want to hoist the gennaker. Thus, there are no lifelines, and the jib boom is arranged to almost sweep the deck. The deck is big and clean, surrounded only by a pretty little varnished teak toe rail.

Staying overnight

I did not want to simply tuck in four berths but instead accomplish some more comfort, without adding kilos – but remember, this is a small boat on the inside! Headroom is only about 1,32 metres (4’4”).
There is a generous double forward with a deck hatch above to give light and ventilation. On the starboard side the bulkhead can be opened, forming a counter space above the w.c., or closed, separating these two compartments. To port, the double berth may be curtained off from the rest of the boat to give some privacy.
Further aft, there is a galley to port and the w.c. to starboard, together with the sink. The w.c. can be made completely private by means of another curtain, arranged to extend from the aft of the keel trunk towards the side of the boat. There is room for a very small water tank under the forward berth. A battery goes in the cockpit stow room. This is charged from shore and used for the few LEDs on board.

The electric installation can also integrate things like a music system, sailing instruments, a chart plotter and an 18 l (2cu.ft.) refrigerator, drawing only 4 watts. 
Aft, there are two ‘easy chairs’ under deck, extending a little way aft under the side decks where the winches are placed. Further aft, the starboard seat is converted into a berth to sleep one more person. To port there is room for bags and sails, also accessible from the cockpit.
Light and ventilation is provided via the forward hatch, a transparent entrance hatch with washboards, and the opening port in the starboard side of the cockpit. In addition to the two fixed ports, Baby Celeste also has two opening ports in the cabin, concealed behind louvered glass grilles which keep rain out, so the boat can be left until the next sail, with windows open.
The visible part of the interior extends 5 metres (16½ ft) forward and aft and 2 metres (7 ft) across.
A square boom tent is attached to the pushpit and could almost make the little Neo appear spacious. It offers a little more headroom in the cockpit (1,6 m) and in the entrance (2 m). The opening part of the bulkhead forward doubles as the cockpit table.

Making it all work
A concept like the Baby Celeste will be possible only if weight is strictly controlled. At the same time, I believe that exotic materials must be avoided in order to keep production cost within reasonable limits.
The Design Challenge called for a simple boat, which is good. Simplicity is a corner stone of any good design. But how does one define simple? As a designer, should you focus on simple handling, or a simple build schedule, or a lack of features, or simplistic / minimalistic shapes? Difficult balance.
Using Vinylester infusion of multi-directional glass rovings on a closed cell PVC core, the construction is made of four basic parts:
1 - The hull, which uses a split mould but is laminated in one piece
2 - The deck and cockpit, including the part of the cabin which is just under the cosmetic roof and houses the keel lifting blocks and all control lines 
3 - The keel casing, which extends forward like an overturned ‘L’ right under the cabin top. This goes together with the deck part, above, to make a proper beam, forming the mast step
4 - The cosmetic roof, which does nothing except look sweet
You could perhaps say that the complication of the design lies in engineering and 3D-modelling the necessary plugs and moulds. Once done, the build process should be straightforward, and handling will be a doddle.
picture by Christian Wallgren
Availability and price
A carbon spar on the Baby Celeste would be an interesting option. And customers will be able to choose the colour of their boat and its roof, the rig, the propulsion, the way it is equipped, sails, cushions, boom tent and the colour of its specially made trailer.
A prototype will start building after summer 2012. 
Price and availability to be annonunced. Please let us know of your possible interest.

Baby Celeste, specifications:

L.O.A.                                         9,25 m      30,3'
D.W.L.                                         8,81 m      28,9'
Beam, maximum                         2,28 m        7,5'
Beam, waterline                          1,64 m        5,4'
Draft                                            2,00 m        6,6'
Displacement, light                      1550 kg     2700 lbs
Disp., w. 2 persons + light load 1760 kg     3100 lbs
Ballast                                         650 kg      990 lbs
Sail areas:
Sail area 100%                            38,6 m²     415 sq.ft.
True sail area                               40,8 m²     439 sq.ft
Mainsail, true area     27,0 m²     290 sq.ft.
Jib, true area              13,8 m²     148 sq.ft.
Gennaker                                     42 m²        452 sq.ft.

D/L                                              73
SA/D, upwind                             26,5
SA/D, downwind                         57
Ballast ratio                                 42 %
WL. entry                                    10,0°