The Shearwater 45 Sailboat
Specs & Key Performance Indicators
The Shearwater 45, an aft-cockpit cutter, was designed by Dudley Dix and built in South Africa by Acheson Yachts.
A Shearwater 45
Published Specification for the Shearwater 45
Underwater Profile: Fin keel & spade rudder
Hull Material: GRP (Fibreglass)
Length Overall: 51'5" (15.7m)
Waterline Length: 37'5" (11.4m)
Beam: 13'1" (4.0m)
Draft: 6'3" (1.9m)
Rig Type: Cutter
Displacement: 27,550lb (12,497kg)
Designer: Dudley Dix
Builder: Acheson Yachts (South Africa)
Year First Built: 1990
Published Design Ratios for the Shearwater 45
1. Sail Area/Displacement Ratio: 20.2
- Less than 16 would be considered under-powered;
- 16 to 20 would indicate reasonably good performance;
- Over 20 suggests relatively high performance.
2. Ballast/Displacement Ratio: 38.0
- Under 40: less stiff, less powerful
- Over 40: stiffer, more powerful
3. Displacement/Length Ratio: 235
- Under 100: Ultralight
- 100 to 200: Light
- 200 to 275: Moderate
- 275 to 350: Heavy
- Over 350: Ultraheavy
4. Comfort Ratio: 33.3
- Under 20 indicates a lightweight racing boat
- 20 to 30 indicates a coastal cruiser
- 30 to 40 indicates a moderate offshore cruising boat
- 40 to 50 indicates a heavy offshore boat
- Over 50 indicates an extremely heavy offshore boat
5. Capsize Screening Formula: 1.7
- Under 2.0 (the lower the better): Better suited for ocean passages
- Over 2.0: Less suited for ocean passages
read more about these Key Performance Indicators...
Summary Analysis of the Design Ratios for the Shearwater 45
1. A Sail Area/Displacement Ratio of 20.2 suggests that, in the right hands, the Shearwater 45 will have enough performance to leave most other sailboats of similar waterline length well astern.
2. A Ballast/Displacement Ratio of 38.2 means that a sailboat like the Shearwater 45 (which doesn't have its ballast concentrated in a bulb at the foot of a deep keel), is likely to benefit from being reefed early to keep her sailing upright in a moderate breeze.
3. A Displacement/Length Ratio of 235, tells us the Shearwater 45 is a moderate displacement cruiser, which means she'll carry all your cruising gear without it having a dramatic effect on her performance. Most of today's sailboats intended for offshore cruising fall into this displacement category.
4. Ted Brewer's Comfort Ratio of 33.3 suggests that crew comfort of a Shearwater 45 in a seaway is similar to what you would associate with the motion of a moderate bluewater cruising boat - a predictable and acceptable motion for most seasoned sailors.
5. The Capsize Screening Formula (CSF) of 1.7 tells us that a Shearwater 45 would be a safer choice of sailboat for an ocean passage than one with a CSF of more than 2.0.
May 16, 22 04:32 AM
Interested in the Etap 32i sailboat? Here are the pics, specs and performance predictions you're looking for...
May 15, 22 10:55 AM
Interested in the X-332 sailboat? Here are the pics, specs and performance predictions you're looking for...
May 14, 22 06:47 AM
Interested in the Jeanneau Sun Odyssey 44 sailboat? Here are the pics, specs and performance predictions you're looking for...