Published Specification for the Dufour Classic 45
Underwater Profile: Bulb fin keel with spade rudder
Hull Material: GRP (Fibreglass)
Length Overall: 45'11" (14.0m)
Waterline Length: 37'5" (11.4m)
Beam: 14.2'x" (4.3m)
Draft: 7'8" (2.3m)
Rig Type: Masthead sloop
Displacement: 24,180lb (10,968kg)
Designer: J&J Design
Builder: Dufour Yachts (France)
Year First Built: 1988
Published Design Ratios for the Dufour Classic 45
1. Sail Area/Displacement Ratio: 17.0
- 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: 36.0
- Under 40: less stiff, less powerful
- Over 40: stiffer, more powerful
3. Displacement/Length Ratio: 206
- Under 100: Ultralight
- 100 to 200: Light
- 200 to 275: Moderate
- 275 to 350: Heavy
- Over 350: Ultraheavy
4. Comfort Ratio: 27.4
- 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: 1.9
- 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 Dufour Classic 45
1. A Sail Area/Displacement Ratio of 17.0 suggests that the Dufour Classic 45 will, in the right conditions, approach her maximum hull speed readily and satisfy the sailing performance expectations of most cruising sailors.
2. A Ballast/Displacement Ratio of 36.0 would usually mean that the Dufour Classic 45 would have a tendency to heel uncomfortably in a gust, and need to be reefed early to keep her sailing upright in a moderate breeze.
However, as she has much of her ballast concentrated in a bulb at the foot of her keel, she's likely to be considerably stiffer than her published Ballast/Displacement Ratio might suggest.
3. A Displacement/Length Ratio of 206 tells us the Dufour Classic 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 27.4 suggests that crew comfort of a Dufour Classic 45 in a seaway is similar to what you would associate with the motion of a coastal cruiser with moderate stability, which is not encouraging news for anyone prone to seasickness.
5. The Capsize Screening Formula (CSF) of 1.9 indicates that a Dufour Classic 45 would be a safer choice of sailboat for an ocean passage than one with a CSF of more than 2.0.