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Performance

King Arthur 35 Performance

How the King Arthur 35 performs on the water — racing handicap, sail-carrying power, stability and comfort.

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The King Arthur 35 is moderately powered for comfortable coastal cruising, with a steady, comfortable ride offshore.

Hull Speed

The theoretical displacement-mode speed limit — determined by waterline length, not engine or sail power.

6.7 kts
A displacement hull pushes a bow wave whose speed is limited by the waterline length. With a waterline of 25.0′, the King Arthur 35 tops out around 6.7 knots in displacement mode — after that, the bow wave outruns the hull and resistance climbs steeply.
1.34 × √25.0′ LWL = 6.7 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
33.6
Good offshore comfort — steady enough for multi-day passages.
Capsize Screening
1.63
Below the 2.0 offshore threshold — acceptable for ocean passages.
Hull Speed
6.7kts
Pounds/Inch Immersion
833lbs
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
33.6
Good offshore comfort — steady enough for multi-day passages.
Under 20 — Snappy, racing motion
20–30 — Acceptable coastal
30–40 — Good offshore comfort
Over 40 — Very comfortable offshore
Capsize Screening Formula
1.63
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 King Arthur 35 sits on the PHRF handicap spectrum — lower numbers mean faster boats.

Racer 0–90
Cruiser/Racer 90–150
Cruiser 150–210
Contessa 35 114s/nm
Cascade 36 150s/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° 2.7 3.4 3.8 3.9
Close Reach60° 3.2 4.1 4.6 4.7
Beam Reach90° 4.0 5.0 5.6 5.8
Broad Reach120–135° 3.7 4.6 5.2 5.4
Run150–180° 2.9 3.7 4.1 4.3
These are simplified estimates based on hull speed (6.7 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 King Arthur 35 — 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 King Arthur 35.

King Arthur 35 Cal Cruising 36 Cascade 36 Contessa 35 Lion Class Robb Robb 35
Dimensions
LOA 35.5 35.5 35.6 35.5 35.5 35.5
LWL 25.0 27.0 28.9 29.5 25.0 24.0
Beam 9.3 10.3 10.0 11.4 8.8 10.0
Displacement 12 12 12 13 14 14
Ballast 5 — 4 6 4 4
Sail Area 554 600 590 623 513 587
Performance
PHRF — — 150 114 — —
SA/Disp 17.0 18.4 17.6 17.6 14.1 15.6
Bal/Disp — — 35.5 51.1 28.2 31.6
Comfort 33.6 28.0 29.1 26.0 43.4 39.0
Capsize 1.63 1.81 1.73 1.92 1.45 1.63
Hull Speed 6.7 7.0 7.2 7.3 6.7 6.6