The Nauticat 33 Sailboat

Specs, Performance Analysis & Cruising Characteristics

Quick Answer / Key Takeaways: The Nauticat 33 is a legendary Finnish-built motorsailer designed for those who value year-round comfort and interior volume over raw sailing speed. Produced by Siltala Yachts between 1967 and 1996, it features a distinctive ketch rig and a sturdy long keel (with later models adopting a fin keel and skeg). While it will not win races to windward, its 80 hp to 90 hp engine ensures reliable progress when the wind fails, and the dual-station steering makes it an ideal choice for northern latitudes. It is best suited for couples or small families seeking a safe, predictable liveaboard for coastal or offshore cruising.

The hull of this Finnish-built Nauticat 33 motorsailer closely resembles that of a traditional Nordic fishing boat. She's a popular cruising yacht for the liveaboard sailor.

The Nauticat 33 at a Glance
Design & Construction
Published Specification: The Nauticat 33 Blueprint
Sail Areas & Rig Dimensions
Performance Analysis: Understanding the Design Ratios
How the Nauticat 33 Sails
Bluewater Capability: Strengths & Trade-Offs
Configuration, Layout & Cruising Characteristics
Who This Boat Is Best For
The Buyer’s Checklist: Common Problem Areas
Summing Up
Frequently Asked Questions (FAQs)

The Nauticat 33 at a Glance

Type: Motorsailer
Designer: W. Aarnipalo
Builder: Siltala Yachts (Finland)
Production Years: 1967–1996
Rig: Masthead Ketch
Best for: Year-round cruising, liveaboards, and coastal exploration in varied climates.
Strengths: Massive interior volume, protected wheelhouse, robust build quality, and excellent range under power.
Trade-offs: Limited windward performance, significant windage from the high superstructure, and "traditional" handling characteristics in tight marinas.

Design & Construction

The Nauticat 33 was the vessel that defined the Siltala Yachts brand, with over 1,160 units launched. Its design philosophy is rooted in the traditional Nordic fishing boat—characterised by a canoe stern, a high freeboard, and a heavy-displacement hull. Early models (pre-1977, often called the MkI) featured a traditional long keel with a very shallow draft, while the later MkII models (post-1977) transitioned to a deeper fin keel and a skeg-hung rudder to improve tracking and manoeuvrability.

Construction is hand-laid solid GRP (glass-reinforced plastic) for the hull, which is renowned for its "tank-like" thickness. A significant evolution occurred in the wheelhouse construction; early versions utilised a wooden wheelhouse which, while beautiful, required high maintenance. Later models replaced this with a GRP wheelhouse, significantly improving durability.

The windows in the wheelhouse are typically secured in heavy frames, though on older models, checking for leaks is a priority as seals can perish over time. The chainplates are robustly bonded into the hull structure, a hallmark of the Finnish yard’s commitment to offshore integrity. While the 33 was primarily a ketch, a handful of sloop-rigged versions exist, though the ketch remains the definitive choice for balancing the sail plan in heavy weather.

Published Specification: The Nauticat 33 Blueprint

Measurement	Value (Imperial & Metric)
L_OA (Length Overall)	33'2" (10.11m)
L_WL (Waterline Length)	28'2" (8.60m)
Beam	10'8" (3.26m)
Draft	4'1" (1.25m) to 5'1" (1.55m) depending on keel
Displacement	17,250 lbs (7,824 kg)
Ballast	5,150 lbs (2,336 kg)
Hull Material	GRP (Solid Laminate)
Production Dates	1967 – 1996

Sail Areas & Rig Dimensions

Rig dimensions

The ketch rig allows for a versatile sail plan, making it easier to manage the total sail area by dropping the mainsail and sailing under "jib and jigger" (headsail and mizzen) when the wind picks up.

Total Sail Area (100% Foretriangle): 475 ft² (44.13 m²)
Main Sail Area: 197 ft² (18.30 m²)
Mizzen Sail Area: 85 ft² (7.90 m²)
I (Forestay Height): 40'9" (12.41m)
J (Foretriangle Base): 13'9" (4.18m)
P (Main Hoist): 35'1" (10.70m)
E (Main Foot): 11'2" (3.41m)

Performance Analysis: Understanding the Design Ratios

The following ratios provide a mathematical perspective on how the Nauticat 33 behaves on the water.

Ratio	Value	Interpretation
Sail Area / Displacement (SA/D)	11.4	Motorsailer territory. This indicates the boat is under-canvassed for light winds and relies on its engine.
Displacement / Length (D/L)	344	Heavy displacement. Suggests a very high load-carrying capacity and a steady, predictable motion in a seaway.
Ballast / Displacement (B/D)	29.9%	Moderately stiff. Much of its stability comes from the hull form and the weight of the engine and tanks low down.
Capsize Screening Formula (CSF)	1.65	Very safe. A value under 2.0 is considered suitable for ocean passages, showing high resistance to capsize.
Brewer Motion Comfort Ratio	38.4	Exceptionally high. This boat will have a slow, easy motion that won't exhaust the crew in rough conditions.

How the Nauticat 33 Sails

Sailing a Nauticat 33 is an exercise in patience and pragmatism. It is not a boat that will point high into the wind; expect a tacking angle closer to 100 degrees or more. In light air, you will almost certainly have the engine ticking over to maintain steerage and speed. However, once the wind moves to a broad reach and exceeds 15 knots, the hull settles into a comfortable groove, often maintaining a steady 6 to 7 knots.

The helm is hydraulic and lacks the "feel" of a cable or rod system, but it is incredibly easy to operate from the warmth of the wheelhouse. Downwind, the ketch rig shines, allowing for several configurations to keep the boat balanced. The motion is remarkably "kind"—it doesn't snap or jerk, but rather rolls gently, making it a favourite for those who suffer from seasickness.

Bluewater Capability: Strengths & Trade-Offs

For offshore work, the Nauticat 33 offers a level of protection few other 33-footers can match. The internal helm station means you can navigate a gale in a t-shirt while staying dry. Fuel and water tankage are generous, often exceeding 300 litres (66 gallons) and 450 litres (99 gallons) respectively, which supports long-range cruising.

The primary trade-off is windage. In a crosswind, the high wheelhouse acts like a sail, making docking a challenge without a bow thruster. Furthermore, while the hull is seaworthy, the large wheelhouse windows are a potential vulnerability in extreme "breaking wave" conditions, though they have stood the test of time for decades.

Configuration, Layout & Cruising Characteristics

The interior is where the Nauticat 33 wins over its owners. With nearly 6'7" (2.00m) of headroom in the wheelhouse and 6'3" (1.90m) below, it feels far larger than its 33' length suggests.

Wheelhouse: Features a large U-shaped settee and a panoramic view. It serves as the primary social hub.

Aft Cabin: A private retreat with a double berth (or twin singles in some layouts) and often its own vanity or head.

Galley & Dinette: Located forward and down from the wheelhouse. The galley is U-shaped and secure for cooking at sea, while the dinette opposite converts into a double berth.

Forecabin: A traditional V-berth for guests or storage.

Who This Boat Is Best For

Good fit for:

Liveaboard couples who want a "home on the water" that feels like a house.
Sailors in cold or rainy climates who want to extend their season.
Retired sailors who prefer the ease of a motorsailer over the physical demands of a performance yacht.

Less ideal for:

Racing enthusiasts or those who enjoy the "art" of trimming sails for speed.
Cruisers in the tropics who may find the wheelhouse gets too hot without significant ventilation or air conditioning.

The Buyer’s Checklist: Common Problem Areas

Wheelhouse Leaks: On wooden-top models, look for rot in the window frames and cabin sides. GRP models should be checked for crazing or failed seals.

Engine Condition: These boats rely heavily on their engines (usually Ford Lehman or Perkins). Ensure a cold start is clean and check for oil leaks.

Teak Decks: Many were built with laid teak decks. If original, they may be reaching the end of their life, which is a significant expense to replace or remove.

Hull Osmosis: Like many boats of this era, check for blistering, particularly on hulls that have spent their lives in warmer waters.

Hydraulic Steering: Check for leaks in the lines and ensures the transition between the inner and outer helm is seamless.

Could this be your ideal cruising boat?

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Summing Up

The Nauticat 33 is a masterclass in compromise. It sacrifices windward performance and sleek aesthetics for an unmatched level of comfort, safety, and interior volume. Its heavy-displacement hull and high comfort ratio make it one of the most stable platforms in its size bracket. While maintenance on older teak and woodwork can be demanding, the build quality of Siltala Yachts ensures that a well-kept 33 is a vessel that will look after its crew in almost any weather.

This article was written by Dick McClary, RYA Yachtmaster and author of the RYA publications 'Offshore Sailing' and 'Fishing Afloat', member of The Yachting Journalists Association (YJA), and erstwhile member of the Ocean Cruising Club (OCC).

Frequently Asked Questions (FAQs)

How does the Nauticat 33 handle in a marina without a bow thruster?

Due to its high windage and long keel (or skeg), the 33 can be a handful in a crosswind. Many owners retro-fit bow thrusters to make close-quarters manoeuvring less stressful.

Can the Nauticat 33 really cross oceans?

Yes, many have. While it isn't a fast passage-maker, its CSF of 1.65 and heavy displacement make it very seaworthy. However, one must ensure the wheelhouse windows are reinforced for serious offshore work.

What is the realistic cruising speed under power?

Most Nauticat 33s cruise comfortably at 6 to 7 knots at approximately 1,800 to 2,000 RPM, depending on the engine.

Is there a big difference between the MkI and MkII?

The MkII is generally preferred for its GRP wheelhouse (less maintenance) and its improved keel/rudder configuration, which offers better handling than the very shallow MkI.

How many people can realistically live aboard?

For long-term cruising, it is perfect for a couple. While it can sleep six, the storage and plumbing are best suited for two people with occasional guests.