OPEN 40 - Customer information
Groupe Finot



The boat has been designed primarily for short-handed offshore competitions, or very fast cruising. It is an exceptional yacht, in terms of performance, quality and reliability. Therefore, every part of its building shall endeavor to save weight as much as possible - while keeping the costs at a reasonable level - yet retaining the necessary strength characteristics of a boat cruising far offshore with large loads due to sea or slamming, hence far within the requirements of Category A of the 94/25 EU RCD,.

The boat is almost entirely made using carbon composites. It is fitted with an ~1600 kg water ballast on each side, which will provide large upwind stability when needed, and will also contribute to make the boat self-righting in the event of an inversion after having been rolled by a large breaking wave.

The boat is also fitted with a carbon fiber CWing Ó rotating wing mast.

Self-righting ability : The angle of vanishing stability in IMOCA conditions is larger than 125°
Unsinkability : 7 independent compartments : aft compartment, main cabin, front cabin, front compartment, two water ballasts. When one compartment is flooded, the boat sinks about 27 cm, when 2 adjoining compartments are flooded, the boat waterline shall be located at mid freeboard.


Hull, deck, and bulkheads are built using the same materials and technical processes as those used for the Open 60 ' class boats.

The hull
Solid T700S carbon fiber hull oven-cured at 120°C, Hexcel M10 prepreg thickness from 3.5 to 13 mm T700S prepreg longitudinal stringers
T700S frames
Carbon/Nomex sandwich bulkhead, thickness 20 mm 48 kg / m3, (prepeg skins)
Vacuum is made as the layers are placed to eliminate the air and to ensure a good cohesion of the laminate.
Several cooking stages will be realized to obtain the best possible result.
These various elements are built and assembled in a female mould.

The deck
Nomex sandwich on a large area (forward deck, top of roof, cockpit …)
Skins made of T700S prepreg, 20mm Nomex core, 48 kg/m3
Solid areas under some deck fittings, joints…

The CWING rigging
Carbon fiber rotating mast held by a forestay and two shrouds, built by Alucarbon using a winding process.
Carbon boom (gooseneck at deck level). No spreaders, backstay, or running backstays. (For severe conditions, a babystay and a pair of lower shrouds are added).

The bowsprit
External retractable bowsprit built by Alucarbon. Manual positioning.
Total length 4120 mm protruding 2500mm. The bowsprit, put on the deck, is held vertically by a bobstay.
At bowsprit end the ultimate lateral strength is 1620 kg

The rudder
The boat has two rudders made of M30S carbon laminate. They are fitted with two Spinlock tiller extensions.
The bearings are self-aligning.

Ballast keel bulb and fin
The bulb is a hydrodynamic profile made of cast lead with at least 3% antimony, weighting 1330 Kg The fin is made of solid prepreg T700S carbon laminate.
For the fixed keel, (3.2 m draft) the fin is assembled in a 400mm high keel box with 3 transverse bolts. For the optional sliding keel, (draft of 3.2 m and 2.04m) the 400 mm keel box remains the same, but is extended to the deck.
A hydraulic locking device prevents any movement of the keel both in the up and down positions.
A device provides energy absorption and damping of shocks due to grounding at low speed .
The keel is lifted by an hydraulic ram pulling on a course multiplying tackle.

The water ballasts
The water ballasts are built using carbon/Nomex sandwich.
2 scoops allow to draw the water
A pump on the engine allows to complete the filling up when the speed is not high enough.
The water ballast are placed low to keep a good stability in every condition.
Each water ballast is divided into two front and aft compartments.

The fittings
The fittings are built using painted sandwich panels, with a wooden border at the top part , then assembled to the structure.
- 2 berths in the crew cabin
- 2 berths on the aft water ballasts
- 2 berths under the cockpit
- galley storage, sink, stove
- navigation station
- toilet storage
- 1 basin
- 1 sea toilet
- Pressurized water with 110 liter tank
- 61 liter fuel tank


Open 40
Main dimensions


Hull length
12,20 m
Maximum beam
4,10 m
3.2 / 2.04 m
4 t
Ballast(of which bulb 1,3 t )
1.5 t
Water bnallast each side
1.6 t
Main Sail + Cwing
89 m²
49/43 m²
Asymmetric Spinnaker
142 m²
14,87 m
5,40 m
18,19 m
6,77 m

Indicative supplied equipment


1. Deck
· Deck painted using single color "International" paint, antislip.
· Toerails integrated to the deck.
· Front cabin (sails storage) accessible through a Lewmar Ocean 60 hatch.
· Liferaft storage on the transom, secured by pad-eyes.
· Sliding companionway panel made of carbon sandwich and stowable PMMA door with lock.
· Self-draining cockpit.
· 2 winch handle pockets in the cockpit.
· Backlit compass.
· Throttle accessible from the helmsman position.
· Storage for the LPG bottle under the backbeam (cartridge not supplied).

2. Pulpits - Lifelines
· Stainless stem pulpit with 2 navigation lights.
· Stainless aft pulpit.
· Stainless tapered braced stanchions.
· Center aft stanchion with navigation light.
· Lifeline open at the transom.
· 2 levels of coated stainless lifelines.

3. Mooring
· 4 aluminum mooring cleats, length 200 mm.

4. Winches
· 2 winch handle pockets in the cockpit.
· 2 genoa sheet Harken 44.2STA winches.
· 2 mainsheet Harken 40.2STA winches.
· 2 auxiliary Harken 40.2STA winches.
· 3 Harken Speed Grip winch handles.

5. Deck hardware
· Harken articulated mast base blocks.
· 2 Harken genoa lead car sytems.
· 2 genoa adjuster systems, led to the cockpit.
· Harken mainsheet traveler with control tackles.
· Double jammers + single jammers + cleats for halyards and control lines.

6. Hatches and portlights
· Sliding companionway panel made of carbon sandwich and stowable PMMA door with lock.
· 4 fixed portlights, Lewmar standard type.
· Lewmar Ocean 60 hatch above the front cabin.
· Lewmar Ocean 10 hatch above the toilet.

7. Lights
· 2 stem navigation light on the pulpit.
· Aft navigation light on center stanchion.
· Mooring light on mast head.


1. Mast - Boom
· T700S carbon fiber wing mast stepped on the keel.
· Mainsail luff track with ball bearing travelers.
· Carbon fiber boom.
· Carbon fiber bowsprit, manually retractable.

2. Standing rigging
· 2 1´19 stainless wire shrouds, 2 1´19 stainless wire lower shrouds, textile babystay, bowsprit bobstay.
· Bridles as boom vang.
· Rod forestay.
· Twin grooves Facnor genoa furler.
· Stainless forestay chainplate at the bow.
· Stainless shrouds chainplates on the hull.

3. Running rigging
· Genoa halyard (Vectran).
· Genaker halyard (Vectran).
· Mainsail halyard with 3:1 purchase (Vectran).
· Lazy jack.
· 2 reefing lines on the boom.
· Mainsail outhaul.
· Genoa sheets (Dynema).
· Mainsheet with tackle (Dynema).
· Mainsheet traveler control lines.
· Genoa furler control line.
· Mast rotation control lines.


1. Engine Compartment : access - soundproofing
· Companionway on hinges.
· Engine compartment soundproofing with 30 mm thick foam.
· 2 100mm ventilation hoses led to the transom.

2. Engine
· Fiberglass/polyester engine support.
· Twin-blade folding propeller.
· 50 Amp alternator.
· 12V, 55 Amp engine battery.

3. Instruments
· Engine panel inside the boat, close to the companionway.

4. Fuel system
· 61 liter fuel tank, with vents, and level indicator.
· Fuel deck filler.
· Water separating fuel filter on engine feeding line


1. Tanks
· 110 liters tank.
· Water filler on the tank.

2. Water pump
· Pressurized cold fresh water to the galley and basin.

3. Taps
· 2 cold water taps at the sink and the basin.

4. Bilge pumps
· 100 liter/min manual pump accessible from inside.
· 100 liter/min manual pump accessible from the cockpit.
· 260 liter/min engine driven pump.

5. WC
· Standard sea toilet.

6. Circuit ballast
· 2 scoops.
· 4 100mm transfer knife valves.
· 3-way valve at bottom of the companionway.
· 260 liters/min engine driven pump with electrical clutch.
· Convertible to bilge pump.

· 12 V electrical wiring harness.
· 50 Amps engine alternator.
· Charge controller.

1. Batteries
· Main switches : negative and positive.
· 12V, 55 Amp engine battery, strapped in its box.
· 3 12V, 75Amp service batteries, strapped in their box.

2. Switches panel
· 12 V, 16 functions switches panel at the navigation station.

3. 12 V utilities
· Pressurized water pump.
· Lights.

4. Interior lights
· 3 fluorescent lights in the front and aft compartments and the front cabin.
· 6 lights in the main cabin and the toilets.
· 1 halogen reading light at the navigation station.

· Storage for the LPG bottle under the backbeam (cartridge not supplied).
· Shock cord bottle holder.
· ¼ turn on-off gas tap on rigid copper pipe.
· Gimbaled twin burner cooker with pan clamps and flame failure safety device on burners.


1. Interior finish and furniture
· Epoxy paint in main cabin and toilets.
· Nomex sandwich accommodations with white polyurethane lacquer finish.

2. Companionway
· Laminated companionway on hinges with 3 curved steps.

3. Cushions and mattresses
· 2 saloon mattresses.
· 2 berth mattresses under the cockpit.
· 2 berth mattresses above the water ballast tanks.
· Cushion on the navigation seat.

4. Navigation station
· Forward facing navigation station.
· Book storage on port side.
· Navigation instruments panel.
· 16 functions switches panel.
· Transverse navigator seat.

5. Galley
· Storage space along the hull.
· Stainless sink with pressurized cold water tap.
· Space for ice box or fridge.
· Gimbaled twin burner cooker with pan clamps and flame failure safety device on burners.


· Front-most bulkhead with sandwich hatch secured with wing nuts.
· Font watertight bulkhead with Lewmar T50 hatch.
· Aft watertight bulkhead with Lewmar T50 hatch.


"International" suggested process
· One color of your choice lacquer finish on hull above water.
· Deck : 1 color of your choice with antislip on the horizontal areas.
· Underwater parts ready for anti-fouling treatment.

This document is non-contractual. All descriptions, illustrations, etc, are only an indication. We reserve the right to modify or improve our productions without notice.


Let see on the website:

- Future of Open boats by Jean-Marie Finot (fév 00)
- The C-wing rig , par pascal conq

- The future sailing par Jean-Marie (fév 00)
- Research at the Groupe Finot

return to open 40