Nauticat 521 Ketch
Description
The Nauticat 521 was a Finnish-built pilothouse motorsailer designed by Sparkman & Stephens as an updated evolution of the earlier Nauticat 52, first produced in 1986 by Siltala Yachts (later Nauticat Yachts Oy) in Pietarsaari, Finland, emphasizing heavy-displacement bluewater seaworthiness, expansive all-weather visibility from its raised deck saloon, and luxurious liveaboard accommodations for families or extended voyages under its masthead ketch rig for balanced, short-handed sail handling. Constructed from solid fiberglass with a fin keel and skeg-hung rudder for protected stability, it displaced 56,000 pounds with 18,000 pounds of lead ballast, measured 51.16 feet LOA, 39.58 feet LWL, 15 feet beam, and 7.16 feet draft, achieving a hull speed of about 8.5 knots and 1,002 square feet of sail area powered by a robust 150 HP Perkins diesel engine with substantial fuel and water capacities for long-range motoring. Renowned for its fortress-like durability, panoramic saloon views, teak-rich interior with multiple cabins sleeping up to 12, dual helms, and ocean-crossing capability, the Nauticat 521 was produced through the early 1990s with a small number of units built (fewer than 20), remaining a rare, premium classic for traditionalists seeking ultimate comfort and reliability on global passages.
Construction Details
| Designer | Sparkman and Stephens |
|---|---|
| Builder | Siltala Yachts |
| Length | 52.000 ft |
| LOA | 39.000 ft |
| LWL | 32.160 ft |
| Beam | 11.500 ft |
| Max Draft | 5.700 ft |
The standard boat dimensions
| i | 63.32 ft |
|---|---|
| j | 25.26 ft |
| p | 56.76 ft |
| e | 15.85 ft |
| p2 | 37.08 ft |
| e2 | 8.43 ft |
| i2 | - |
| j2 | - |
| I | J | P | E | P2 | E2 | I2 | J2 |
|---|---|---|---|---|---|---|---|
| 63.32 ft | 25.26 ft | 56.76 ft | 15.85 ft | 37.08 ft | 8.43 ft | - | - |
Sails
Nauticat 521 Ketch - MAINSAIL
| Luff | * 56.76 ft - (17300 mm) |
|---|---|
| Foot | * 15.85 ft - (4831 mm) |
| Leech | * 58.26 ft - (17758 mm) |
| Tack Angle | * 87.98 ° |
| Diagonal | * 58.39 ft - (17797 mm) |
| Head (inches) | * 6 in - (152 mm) |
| Area | 449.39 ft² |
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Nauticat 521 Ketch - JIBSAIL
| Luff | * 54.54 ft - (16624 mm) |
|---|---|
| Foot | * 34.94 ft - (10650 mm) |
| Leech | * 45.59 ft - (13896 mm) |
| Percentage LP | * 115 % |
| Length Perpendicular | * 29.05 ft - (8854 mm) |
| Deck Angle | * 12 ° |
| Area | 792.31 ft² |
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Nauticat 521 Ketch - GENOA
| Luff | * 64.76 ft - (19739 mm) |
|---|---|
| Foot | * 42.07 ft - (12823 mm) |
| Leech | * 59.97 ft - (18279 mm) |
| Percentage LP | * 150 % |
| Length Perpendicular | * 37.89 ft - (11549 mm) |
| Deck Angle | * 4 ° |
| Area | 1226.94 ft² |
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Nauticat 521 Ketch - MIZZEN
| Luff | * 37.08 ft - (11302 mm) |
|---|---|
| Foot | * 8.43 ft - (2569 mm) |
| Leech-AftHdBd | * 37.67 ft - (11482 mm) |
| Tack Ang | * 88.01 ° |
| Diag (clew/head) | * 37.74 ft - (11503 mm) |
| Head (inches) | * 4 in - (102 mm) |
| Area (no Roach) | 156.15 ft² |
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Disclaimer. Boats are not all the same -- even when produced in the same factory of the same model. Sailrite does its best to publish accurate dimensions, but we often find it worthwhile to have our customers measure their boats carefully before we produce kits for them. You should take the same precautions, especially when the data is not from Sailrite. The information on this site is not guaranteed to be accurate. Sailrite offers this content as a service to our community, but takes no responsibility for the reliability of the data provided.