Review of Nauticat 33

Nauticat 33
Nauticat 33 anno 1980. Tur til Anholt den 30. juli 2004, 04:39:12

Basic specs.

sail specifications
The Nauticat 33 is a motorsailer designed by the Finnish maritime architect Wilho Aarnipalo in the late sixties. A few thousand boats have been produced. The Nauticat 33 is built by the Finnish yard Siltala Yachts Oy.

Looking for a new boat? Find a Nauticat 33 or similar boat for sale

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.
The hull is a double hull which improves the indoor climate. Especially when the water is colder than the air in the cabin, then the double hull insulates against cold water and reduce the condense water in the cabin.
The deck is a double deck which improves the indoor climate.

The boat is equipped with 4 cabins, 6-7 berths, a galley and toilet facility.


The Nauticat 33 is equipped with a long keel. A long 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 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.

The boat can enter most marinas as the draft is just about 1.55 - 1.65 meter (5.09 - 5.39 ft) dependent on the load. See immersion rate below.


Nauticat 33 is typically equipped with a Ford Lehman 2725E diesel engine.

The fuel tank which is made of stainless steel has a capacity of 600.0 liters (158 US gallons, 131 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 Nauticat 33 is 1.68, 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 7.1 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 Nauticat 33 is about 187 kg/cm, alternatively 1051 lbs/inch.
Meaning: if you load 187 kg cargo on the boat then it will sink 1 cm. Alternatively, if you load 1051 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 Nauticat 33 is 36.4.

Low High 96% 0 50 100
Comparing this ratio with similar sailboats show that it is more comfortable than 96% 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 Nauticat 33 is 3.10.

Slim Wide 62% 0 50 100
Compared with other similar sailboats it is more spacy than 62% 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 Nauticat 33 is 33%.

Low High 15% 0 50 100
This ballast ratio shows a righting moment that is higher than 15% of all similar sailboat designs. A righting moment (ability to resist heeling) significantly below average.

D/L (Displacement Length Ratio)

What is Displacement Length Ratio?

The DL-ratio for Nauticat 33 is 328 which categorizes this boat among 'heavy cruisers'.

Heavy Light 15% 0 50 100
15% 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.


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 21m2 (226 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.


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
Jib sheet 10.1 m(33.2 feet)12 mm(1/2 inch)
Genoa sheet10.1 m(33.2 feet)12 mm(1/2 inch)
Mainsheet 25.3 m(83.0 feet)12 mm(1/2 inch)
Spinnaker sheet22.3 m(73.0 feet)12 mm(1/2 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.


We are always looking for new photos. If you can contribute with photos for Nauticat 33 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.