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Review of Najad 343


Najad 343
Najad 343.

Basic specs.

sail specifications
The Najad 343 is a motorsailer designed by the Swedish maritime architect Olle Enderlein in the early eighties. The Najad 343 is built by the Swedish yard Najad Varvet AB.

Looking for a new boat? Find a Najad 343 or similar boat for sale

Hull
Both the hull and the deck is made of fibreglass. Generally, a hull made of fibreglass requires only a minimum of maintenance during the sailing season.

Interior
The interior is like many other boats made of mahogany.
The boat is equipped with 6 - 7 berths, a galley and toilet facility.
Note: the boat has also been sold to be self-made/-interiored, which means that the quality of each boat may vary.

Rig
Rig
Rig of Najad 343 anno 1983.
The boat equipped with a masthead rig. The advantage of a masthead rig is its simplicity and the fact that a given sail area - compared with a fractional rig - can be carried lower and thus with less heeling moment.

Keel
Keel
Keel of Najad 343.

The Najad 343 is equipped with a fin keel. The fin keel is the most common keel and provides splendid manoeuvrability. The downside is that it has less directional stability than a long keel.

The keel is made of iron. Many people prefer lead keel in favour of iron. The main argument is that lead is much heavier than iron and a lead keel can therefore be made smaller which again result in less wet surface, i.e. less drag. In fact iron is quite heavy, just 30% less heavy than lead, so the advantage of a lead keel is often overstated. As the surface of a fin type keel is just a fraction of the total wet surface, the difference between an iron keel and a lead keel can in reality be ignored for cruising yachts.

Najad 343 can enter most marinas as the draft is just about 1.65 - 1.75 meter (5.41 - 5.71 ft) dependent on the load. See immersion rate below.


Engine

The boat is typically equipped with an inboard Volvo Penta MD17D diesel engine at 35.0 hp (26 kW), which gives a max speed about 6.2 knots.

The transmission is a shaft drive. A shaft drive will in the long run require less maintenence than other types of drive e.g. a sail drive.

The fuel tank which is made of stainless steel has a capacity of 200.0 liters (52 US gallons, 43 imperial gallons).


Sailing characteristics

This section covers widely used rules of thumb to describe the sailing characteristics. Please note that even though the calculations are correct, the interpretation of the results might not be valid for extreme boats.

Stability and Safety

What is Capsize Screening Formula (CSF)?

The capsize screening value for Najad 343 is 1.80, indicating that this boat could - if evaluated by this formula alone - be accepted to participate in ocean races.


Theoretical Maximum Hull Speed

What is Theoretical Maximum Hull Speed?

The theoretical maximal speed of a displacement boat of this length is 7.2 knots. The term "Theoretical Maximum Hull Speed" is widely used even though a boat can sail faster. The term shall be interpreted as above the theoretical speed a great additional power is necessary for a small gain in speed.


Immersion rate

The immersion rate is defined as the weight required to sink the boat a certain level. The immersion rate for Najad 343 is about 194 kg/cm, alternatively 1086 lbs/inch.
Meaning: if you load 194 kg cargo on the boat then it will sink 1 cm. Alternatively, if you load 1086 lbs cargo on the boat it will sink 1 inch.


Sailing statistics

This section is statistical comparison with similar boats of the same category. The basis of the following statistical computations is our unique database with more than 26,000 different boat types and 350,000 data points.

Motion Comfort Ratio

What is Motion Comfort Ratio (MCR)?

The Motion Comfort Ratio for Najad 343 is 30.3.

Low High 79% 0 50 100
Comparing this ratio with similar sailboats show that it is more comfortable than 79% of all similar sailboat designs. This is a comfort value significantly above average.


L/B (Length Beam Ratio)

What is L/B (Length Beam Ratio)?

The l/b ratio for Najad 343 is 3.06.

Slim Wide 66% 0 50 100
Compared with other similar sailboats it is more spacy than 66% of all other designs. It seems that the designer has chosen a slightly more spacy hull design.


Ballast Ratio

What is a Ballast Ratio?

The ballast ratio for Najad 343 is 38%.

Low High 34% 0 50 100
This ballast ratio shows a righting moment that is higher than 34% of all similar sailboat designs. A righting moment (ability to resist heeling) just below average.


D/L (Displacement Length Ratio)

What is Displacement Length Ratio?

The DL-ratio for Najad 343 is 275 which categorizes this boat among 'light crusers & offshore racers'.

Heavy Light 38% 0 50 100
38% of all similar sailboat designs are categorized as heavier. A heavy displacement combined with smaller water plane area has lower acceleration and is more comfortable.


SA/D (Sail Area Displacement ratio)

What is SA/D (Sail Area Displacement ratio)?

The SA/D for Najad 343 with ISO 8666 reference sail is 13.5, with a 135% genua the SA/D is 15.7.

Low High 12% 0 50 100
The SA/D ratio indicates that it is faster than 12% of all similar sailboat designs in light wind.
Don't panic! It is expected that motor sailers has a low SA/D value as this is the natural consequence of the design combining sailing and motor boat characteristics.


Over- / underrigged

Low High 34% 0 50 100
The Najad 343 has more rig than 34% of all similar sailboats, which indicates that the boat is slightly underrigged.
It is expected that motor sailers are underrigged as this is the natural consequence of combining sailing and motor characteristics.


RSP (Relative Speed Performance)

What is Relative Speed Performance?

The Relative Speed Performance for Najad 343 is 12

Slow Fast 12% 0 50 100
The relative speed performance is 12 which means that a it is faster than 12% of all similar sailboat designs. As this boat is a motor sailer, it is expected that the performance of a motor sailer for sail alone is lower than a dedicated sailboat.


Maintenance

Bottom Paint

When buying anti-fouling bottom paint, it's nice to know how much to buy. The surface of the wet bottom is about 32m2 (344 ft2).
Based on this, your favourite maritime shop can tell you the quantity you need.

Note: If you use a paint roller you will need more paint than if you use a paintbrush.


Rig

Dimensions of sail for masthead rig.

mainsail specifications genoa specifications spinnaker specifications

Are your sails worn out? You might find your next sail here: Sails for Sale



If you need to renew parts of your running rig and is not quite sure of the dimensions, you may find the estimates computed below useful.



Guiding dimensions of running rig
UsageLengthDiameter
Mainsail halyard 29.1 m(95.3 feet)10 mm(3/8 inch)
Jib/genoa halyard29.1 m(95.3 feet)10 mm(3/8 inch)
Spinnaker halyard29.1 m(95.3 feet)10 mm(3/8 inch)
Jib sheet 10.2 m(33.5 feet)12 mm(1/2 inch)
Genoa sheet10.2 m(33.5 feet)12 mm(1/2 inch)
Mainsheet 25.5 m(83.7 feet)12 mm(1/2 inch)
Spinnaker sheet22.4 m(73.6 feet)12 mm(1/2 inch)
Cunningham4.3 m(14.3 feet)10 mm(3/8 inch)
Kickingstrap8.7 m(28.5 feet)10 mm(3/8 inch)
Clew-outhaul8.7 m(28.5 feet)10 mm(3/8 inch)

Boat owner's ideas

This section shown boat owner's changes, improvements, etc. Here you might find inspiration for your boat.

Do you have changes/improvements you would like to share? Upload a photo and describe what to look for.



Finally

We are always looking for new photos. If you can contribute with photos for Najad 343 it would be a great help.

If you have any comments to the review, improvement suggestions, or the like, feel free to contact us. Criticism helps us to improve.



References