The Cap Horn is aggressively canvassed for its weight, with a quick, snappy motion best suited to day sailing.
Hull Speed
The theoretical displacement-mode speed limit — determined by waterline length, not engine or sail power.
A displacement hull pushes a bow wave whose speed is limited by the waterline length.
With a waterline of 19.7′, the Cap Horn tops out around 5.9 knots in displacement mode — after that, the bow wave outruns the hull and resistance climbs steeply.
1.34 × √19.7′ LWL = 5.9 kts
Performance Ratios
Racing handicap, sail-carrying power, stability and comfort — and what each one actually tells you about a day on the water.
SA / Displacement
24.3
Performance-oriented — carries a lot of canvas for its weight.
Ballast / Displacement
44.0%
Stiff enough to carry a big genoa comfortably into moderate breeze.
Displacement / Length
117
Ultralight — responsive and fast, but carries less stores.
Comfort Ratio
11.3
Quick, snappy motion — better for day sails and racing than long passages.
Capsize Screening
2.25
Above the 2.0 offshore threshold — best suited for coastal and protected waters.
Pounds/Inch Immersion
498lbs
Weight needed to sink the hull one inch — loading sensitivity.
Motion & Offshore Suitability
Two ratios that matter most when you're planning passages — how the boat feels in a seaway, and whether the hull geometry is suitable for open ocean.
Comfort Ratio
11.3
Quick, snappy motion — better for day sails and racing than long passages.
Under 20 — Snappy, racing motion
20–30 — Acceptable coastal
30–40 — Good offshore comfort
Over 40 — Very comfortable offshore
Capsize Screening Formula
2.25
Above the 2.0 offshore threshold — best suited for coastal and protected waters.
Under 2.0 — Acceptable for offshore
Over 2.0 — Coastal / protected waters
Estimated Speed by Wind
Rough boat speed estimates at different true wind speeds and points of sail — derived from hull speed, SA/D, and displacement, not measured polars.
| Point of Sail |
6 kts TWS |
10 kts TWS |
15 kts TWS |
20 kts TWS |
| Close-hauled40–50° |
2.8 |
3.5 |
4.0 |
4.1 |
| Close Reach60° |
3.4 |
4.3 |
4.8 |
5.0 |
| Beam Reach90° |
4.2 |
5.2 |
5.9 |
6.4 |
| Broad Reach120–135° |
3.8 |
4.8 |
5.4 |
5.9 |
| Run150–180° |
3.1 |
3.9 |
4.3 |
4.5 |
These are simplified estimates based on hull speed (5.9 kts),
SA/D (24.3), and empirical efficiency curves — not instrument-measured
polars. Real-world speed varies with sea state, bottom condition, sail trim, and current.
Speeds in gold approach hull speed;
bold gold means near or at hull speed.
Wind Range & Comfort Envelope
Estimated wind ranges for comfortable sailing on the Cap Horn — based on sail area, ballast, and displacement characteristics.
Ghost
Sweet Spot
Reef
Heavy
0–5 kts
5–18 kts
18–28 kts
28+ kts
Ghosting
0–5 kts
Light air, motor-sailing likely. Need patience and a light genoa.
Sweet Spot
5–18 kts
Comfortable under full sail. Best speed-to-comfort ratio.
Time to Reef
18–28 kts
Time to shorten sail. Reef the main, swap to a working jib.
Heavy Weather
28+ kts
Storm conditions. Storm jib or bare poles. Seek shelter if coastal.
How It Compares
Side-by-side with the boats most often cross-shopped against the Cap Horn.
|
Cap Horn |
Golif Jouet |
Muscadet |
Splinter 21 |
Sylphe Dufour |
Trotter |
| Dimensions |
| LOA |
21.3 |
21.3 |
21.3 |
21.2 |
21.4 |
21.3 |
| LWL |
19.7 |
19.4 |
18.4 |
17.0 |
19.3 |
18.5 |
| Beam |
7.1 |
7.4 |
7.4 |
6.8 |
7.9 |
6.9 |
| Displacement |
2 |
2 |
2 |
2 |
3 |
2 |
| Ballast |
880 |
1 |
1 |
900 |
882 |
— |
| Sail Area |
240 |
232 |
205 |
163 |
222 |
— |
| Performance |
| SA/Disp |
24.3 |
18.4 |
17.2 |
13.2 |
16.4 |
— |
| Bal/Disp |
44.0 |
36.9 |
43.3 |
— |
— |
— |
| Comfort |
11.3 |
15.4 |
14.8 |
18.2 |
15.7 |
— |
| Capsize |
2.25 |
2.09 |
2.15 |
1.95 |
2.15 |
— |
| Hull Speed |
5.9 |
5.9 |
5.7 |
5.5 |
5.9 |
— |