Review of Najad 34

Najad 34 anno 1977.

Basic specs.

The Najad 34 is a motorsailer designed by the Swedish maritime architect Olle Enderlein in the early seventies. Several hundred boats have been produced. The Najad 34 is built by the Swedish yard Najad Varvet AB.

Looking for a new boat? Find a Najad 34 or similar boat for sale

Hull

The hull is made of fibreglass. Generally, a hull made of fibreglass requires only a minimum of maintenance during the sailing season.

Interior

The boat is equipped with 3 cabins, 6 berths, a galley, 220.0 liter fresh water capacity and toilet facility.

Rig

Rig of Najad 34 anno 1975. Najad 34 with doghouse

The boat has more than one rig.

One option is 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 of Najad 34 anno 1978.

Full keel

The Najad 34 is equipped with a long keel. A full keel provide a better directional stability than a similar boat with a fin keel; on the other hand, better directional stability means also that the boat is more difficult to handle in a harbour with less space.

The keel is made of lead. Compared with iron, lead has the advantage of being 44% heavier, which allows a smaller keel and hence less water resistance and higher speed.

Najad 34 can enter most marinas as the draft is just about 1.60 - 1.70 meter (5.25 - 5.55 ft) dependent on the load. See immersion rate below.

Engine

The Najad 34 has been equipped with different engine alternatives.

Alternative 1:

The boat may be equipped with an inboard Volvo Penta MD17F diesel engine

Alternative 2:

The boat may be equipped with an inboard Volvo Penta MD17C diesel engine at 35 hp (26 kW). The speed is 8.0 knots.

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

The fuel tank has a capacity of 150.0 liters (39 US gallons, 32 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 34 is 1.72, 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 7.0 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 34 is about 174 kg/cm, alternatively 976 lbs/inch.
Meaning: if you load 174 kg cargo on the boat then it will sink 1 cm. Alternatively, if you load 976 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 34 is 31.2.

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 34 is 3.37.

Compared with other similar sailboats it is slimmer than 66% of all other designs. It seems that the designer has chosen a slightly more speedy hull design.

Ballast Ratio

What is a Ballast Ratio?

The ballast ratio for Najad 34 is 42%.

This ballast ratio shows a righting moment that is higher than 58% of all similar sailboat designs. A righting moment (ability to resist heeling) just above average.

D/L (Displacement Length Ratio)

What is Displacement Length Ratio?

The DL-ratio for Najad 34 is 282 which categorizes this boat among 'medium weight cruisers'.

34% 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 34 with ISO 8666 reference sail is 13.4, with a 135% genua the SA/D is 15.8.

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

The Najad 34 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 34 is 1

The relative speed performance is 1 which means that a it is faster than 1% 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 30m² (322 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.

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**
Masthead rig
Usage	Length		Diameter
Mainsail halyard	26.8 m	(87.9 feet)	10 mm	(3/8 inch)
Jib/genoa halyard	26.8 m	(87.9 feet)	10 mm	(3/8 inch)
Spinnaker halyard	26.8 m	(87.9 feet)	10 mm	(3/8 inch)
Jib sheet	10.4 m	(34.3 feet)	12 mm	(1/2 inch)
Genoa sheet	10.4 m	(34.3 feet)	12 mm	(1/2 inch)
Mainsheet	26.1 m	(85.7 feet)	12 mm	(1/2 inch)
Spinnaker sheet	23.0 m	(75.4 feet)	12 mm	(1/2 inch)
Cunningham	4.2 m	(13.6 feet)	10 mm	(3/8 inch)
Kickingstrap	8.3 m	(27.2 feet)	10 mm	(3/8 inch)
Clew-outhaul	8.3 m	(27.2 feet)	10 mm	(3/8 inch)
Masthead rig
Usage	Length		Diameter
Mainsail halyard	29.4 m	(96.5 feet)	10 mm	(3/8 inch)
Jib/genoa halyard	29.4 m	(96.5 feet)	10 mm	(3/8 inch)
Spinnaker halyard	29.4 m	(96.5 feet)	10 mm	(3/8 inch)
Jib sheet	10.4 m	(34.3 feet)	12 mm	(1/2 inch)
Genoa sheet	10.4 m	(34.3 feet)	12 mm	(1/2 inch)
Mainsheet	26.1 m	(85.7 feet)	12 mm	(1/2 inch)
Spinnaker sheet	23.0 m	(75.4 feet)	12 mm	(1/2 inch)
Cunningham	4.2 m	(13.6 feet)	10 mm	(3/8 inch)
Kickingstrap	8.3 m	(27.2 feet)	10 mm	(3/8 inch)
Clew-outhaul	8.3 m	(27.2 feet)	10 mm	(3/8 inch)

Boat owner's ideas

This section is reserved boat owner's modifications, improvements, etc. Here you might find (or contribute with) inspiration for your boat.

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

Photographer: Wortmann
Rigg 17 m über Wasser: Modifikation für Leichtwind / Schraube verstellbar.

Finally

We are always looking for new photos. If you can contribute with photos for Najad 34 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

[Ref 1]: ISO 8666 Small craft — Principal data.
[Ref 3]: ISO 12215-5 Small craft — Hull construction and scantlings.