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Performance & Speed

Sakonnet One Design Performance

How the Sakonnet One Design performs on the water — racing handicap, speed, sail-carrying power, stability and comfort.

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The Sakonnet One Design is moderately powered for comfortable coastal cruising, 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.

5.1 kts
A displacement hull pushes a bow wave whose speed is limited by the waterline length. With a waterline of 14.4′, the Sakonnet One Design tops out around 5.1 knots in displacement mode — after that, the bow wave outruns the hull and resistance climbs steeply.
1.34 × √14.4′ LWL = 5.1 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
17.0
Moderate sail power — a capable coastal cruiser, not overpowered.
Comfort Ratio
19.6
Quick, snappy motion — better for day sails and racing than long passages.
Capsize Screening
1.90
Below the 2.0 offshore threshold — acceptable for ocean passages.
Hull Speed
5.1kts
Pounds/Inch Immersion
322lbs
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
19.6
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
1.90
Below the 2.0 offshore threshold — acceptable for ocean passages.
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° 2.0 2.6 2.9 3.0
Close Reach60° 2.4 3.1 3.5 3.6
Beam Reach90° 3.0 3.8 4.2 4.4
Broad Reach120–135° 2.8 3.5 3.9 4.1
Run150–180° 2.2 2.8 3.1 3.3
These are simplified estimates based on hull speed (5.1 kts), SA/D (17.0), 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 Sakonnet One Design — based on sail area, ballast, and displacement characteristics.

Ghost
Sweet Spot
Reef
Heavy
0–7 kts 7–20 kts 20–28 kts 28+ kts
Ghosting
0–7 kts
Light air, motor-sailing likely. Need patience and a light genoa.
Sweet Spot
7–20 kts
Comfortable under full sail. Best speed-to-comfort ratio.
Time to Reef
20–28 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 Sakonnet One Design.

Sakonnet One Design Alden O Class Mk Ii Blackwater 18 Geary 18 Goldeneye Herreshoff Y Flyer
Dimensions
LOA 18.3 18.2 18.4 18.2 18.3 18.2
LWL 14.4 15.4 16.0 15.8 14.5
Beam 6.3 6.7 6.4 5.5 6.3 5.7
Displacement 2 2 5 525 2 500
Ballast 700 550 1 1
Sail Area 183 192 178 200 193 161
Performance
SA/Disp 17.0 19.4 9.0 49.2 16.8 41.0
Bal/Disp 27.5 21.9 52.8
Comfort 19.6 15.2 43.6 5.2 20.0 4.9
Capsize 1.90 2.12 1.45 2.71 1.87 2.86
Hull Speed 5.1 5.3 5.4 5.3 5.3 5.1