Swan 391 vs Swan 47
How do the Swan 391 and Swan 47 compare? Below, their dimensions, displacement, sail area and the standard design ratios side by side, followed by a data-driven summary.
Swan 391 
Swan 47 | Swan 391 | Swan 47 | |
|---|---|---|
| Length overall | 33.1 ft10.08 m | 36.3 ft11.05 m |
| Waterline length | 33.1 ft10.08 m | 36.3 ft11.05 m |
| Beam | 12.4 ft3.79 m | 13.8 ft4.19 m |
| Draft | 7.2 ft2.19 m | 7.6 ft2.33 m |
| Displacement | 18,900 lb8,573 kg | 32,408 lb14,700 kg |
| Ballast | 6,800 lb3,084 kg | 15,500 lb7,031 kg |
| Sail area | 767 ft²71.3 m² | 1,366 ft²126.9 m² |
| SA / Displacement | 17.30 | 21.50 |
| Displacement / Length | 233 | 304 |
| Comfort ratio | 30.8 | 42.1 |
| Capsize screening | 1.87 | 1.73 |
| Hull speed (kn) | 7.7 | 8.1 |
Swan 391 vs Swan 47: the short version
- The Swan 47 is the larger boat at 36.3 ft11.05 m LOA versus 33.1 ft10.08 m for the Swan 391.
- The Swan 47 is heavier, displacing about 71% more, which usually means a steadier but slower-to-accelerate hull.
- On sail area/displacement the Swan 47 carries the more powerful rig (21.5 vs 17.3), favouring lighter-air performance.
- The Swan 47 scores higher on the Brewer comfort ratio, suggesting an easier motion in a seaway.
- By the capsize screening formula the Swan 47 rates better for offshore work (1.73 vs 1.87).
Ratios are guidelines computed from published specs; condition, layout and gear matter as much as the numbers.