The Seaforth 24 is modestly canvassed and unhurried, with acceptable motion comfort for coastal passages.
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 17.0′, the Seaforth 24 tops out around 5.5 knots in displacement mode — after that, the bow wave outruns the hull and resistance climbs steeply.
1.34 × √17.0′ LWL = 5.5 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
12.8
Modestly canvassed — a comfortable, unhurried cruiser.
Ballast / Displacement
38.1%
Stiff enough to carry a big genoa comfortably into moderate breeze.
Displacement / Length
382
Heavy displacement — a slow, steady, seakindly hull.
Comfort Ratio
23.9
Acceptable coastal comfort — fine for weekends, notice the chop offshore.
Capsize Screening
1.82
Below the 2.0 offshore threshold — acceptable for ocean passages.
Pounds/Inch Immersion
445lbs
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
23.9
Acceptable coastal comfort — fine for weekends, notice the chop offshore.
Under 20 — Snappy, racing motion
20–30 — Acceptable coastal
30–40 — Good offshore comfort
Over 40 — Very comfortable offshore
Capsize Screening Formula
1.82
Below the 2.0 offshore threshold — acceptable for ocean passages.
Under 2.0 — Acceptable for offshore
Over 2.0 — Coastal / protected waters
PHRF Fleet Position
Where the Seaforth 24 sits on the PHRF handicap spectrum — lower numbers mean faster boats.
Cruiser 150–210
Heavy Cruiser 210–300
Neptune 24 Fk
222s/nm
San Juan 24
222s/nm
Windrose 24
254s/nm
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° |
1.9 |
2.4 |
2.7 |
2.8 |
| Close Reach60° |
2.3 |
3.0 |
3.3 |
3.4 |
| Beam Reach90° |
2.9 |
3.6 |
4.1 |
4.2 |
| Broad Reach120–135° |
2.7 |
3.4 |
3.7 |
3.9 |
| Run150–180° |
2.1 |
2.7 |
3.0 |
3.1 |
These are simplified estimates based on hull speed (5.5 kts),
SA/D (12.8), 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 Seaforth 24 — based on sail area, ballast, and displacement characteristics.
Ghost
Sweet Spot
Reef
Heavy
0–8 kts
8–22 kts
22–30 kts
30+ kts
Ghosting
0–8 kts
Light air, motor-sailing likely. Need patience and a light genoa.
Sweet Spot
8–22 kts
Comfortable under full sail. Best speed-to-comfort ratio.
Time to Reef
22–30 kts
Time to shorten sail. Reef the main, swap to a working jib.
Heavy Weather
30+ 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 Seaforth 24.
|
Seaforth 24 |
Cal 2 24 |
J24 |
Neptune 24 Fk |
San Juan 24 |
Windrose 24 |
| Dimensions |
| LOA |
24.0 |
24.0 |
24.0 |
24.0 |
24.0 |
24.0 |
| LWL |
17.0 |
19.2 |
20.0 |
21.0 |
19.5 |
21.4 |
| Beam |
7.3 |
7.8 |
8.9 |
8.0 |
8.0 |
7.8 |
| Displacement |
4 |
3 |
3 |
3 |
3 |
2 |
| Ballast |
1 |
1 |
950 |
1 |
1 |
700 |
| Sail Area |
208 |
271 |
262 |
250 |
246 |
222 |
| Performance |
| PHRF |
— |
— |
— |
222 |
222 |
254 |
| SA/Disp |
12.8 |
18.2 |
19.8 |
18.5 |
18.2 |
19.9 |
| Bal/Disp |
38.1 |
37.8 |
— |
— |
51.6 |
— |
| Comfort |
23.9 |
18.1 |
12.3 |
14.2 |
14.9 |
10.8 |
| Capsize |
1.82 |
2.01 |
2.44 |
2.17 |
2.17 |
2.34 |
| Hull Speed |
5.5 |
5.9 |
6.0 |
6.1 |
5.9 |
6.2 |