Swan 391
Oy Nautor AB · designed by Ron Holland · 1981
fin keelBermuda rigNew Zealand
The Swan 391 is a 33-foot bermuda rig sailboat designed by Ron Holland and built by Oy Nautor AB, first launched in 1981.
General
| Builder | Oy Nautor AB |
|---|---|
| Designer | Ron Holland |
| Years built | 1981 |
| Hull type | fin keel |
| Rig type | Bermuda rig |
| Construction | fiberglass |
| Origin | New Zealand |
Dimensions
| LOA | 33.07 ft10.08 m |
|---|---|
| LWL | 33.07 ft10.08 m |
| Beam | 12.43 ft3.79 m |
| Draft (max) | 7.19 ft2.19 m |
| Displacement | 18,900 lb8,573 kg |
| Ballast | 6,800 lb3,084 kg |
| Sail Area | 767 ft²71.3 m² |
Design ratios
Computed from the specs above using the standard formulas. Try the sailboat calculators with your own numbers.
SA / Displacement 17.30 Cruiser — good all-round performance
Ballast / Displacement 36.0 % Higher = stiffer / more sail-carrying power
Displacement / Length 233 Moderate
Comfort Ratio 30.8 Moderate bluewater
Capsize Screening 1.87 Suited to offshore passages (≤ 2.0)
Hull Speed 7.7 kn Theoretical max displacement speed
How these numbers are calculated
- SA / Displacement
SA ÷ (Disp ÷ 64)^(2/3)— Power-to-weight. < 16 under-canvassed, 16–20 cruiser, > 20 racer.- Ballast / Displacement
Ballast ÷ Disp × 100— Stability/stiffness. Higher carries sail better.- Displacement / Length
Disp(lt) ÷ (0.01 · LWL)³— < 100 ultralight, 100–200 light, 200–300 moderate, > 300 heavy.- Comfort Ratio (Brewer)
Disp ÷ (0.65 · (0.7·LWL + 0.3·LOA) · Beam^1.33)— Motion in a seaway. Higher = more comfortable offshore.- Capsize Screening
Beam ÷ (Disp ÷ 64)^(1/3)— ≤ 2.0 favored for offshore; > 2.0 better for coastal use.- Hull Speed
1.34 · √LWL— Theoretical max displacement speed in knots.
Estimated price
$31,000 typical range $25,000 – $37,000
⚠ Rough estimate only — not market data. Derived from a simple model based on length and hull age; actual asking prices vary widely with condition, equipment, engine hours and location.
