Rob Roy 23
Marine Concepts · designed by Edward S. Brewer · 1980
centerboard keelketchUnited States
The Rob Roy 23 is a 23-foot ketch sailboat designed by Edward S. Brewer and built by Marine Concepts, first launched in 1980.
General
| Builder | Marine Concepts |
|---|---|
| Designer | Edward S. Brewer |
| Years built | 1980 |
| Hull type | centerboard keel |
| Rig type | ketch |
| Construction | fiberglass |
| Origin | United States |
Dimensions
| LOA | 22.67 ft6.91 m |
|---|---|
| LWL | 21.00 ft6.40 m |
| Beam | 6.92 ft2.11 m |
| Draft (max) | 4.67 ft1.42 m |
| Displacement | 2,800 lb1,270 kg |
| Ballast | 900 lb408 kg |
| Sail Area | 255 ft²23.7 m² |
Design ratios
Computed from the specs above using the standard formulas. Try the sailboat calculators with your own numbers.
SA / Displacement 20.54 Performance / racer — powered up
Ballast / Displacement 32.1 % Higher = stiffer / more sail-carrying power
Displacement / Length 135 Light
Comfort Ratio 15.3 Racing / light coastal
Capsize Screening 1.96 Suited to offshore passages (≤ 2.0)
Hull Speed 6.1 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
$14,500 typical range $11,500 – $17,500
⚠ 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.
