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Performance

Defender 35 Performance

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

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The Defender 35 is well-powered with enough sail area to move in light air, 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.

7.2 kts
A displacement hull pushes a bow wave whose speed is limited by the waterline length. With a waterline of 29.1′, the Defender 35 tops out around 7.2 knots in displacement mode — after that, the bow wave outruns the hull and resistance climbs steeply.
1.34 × √29.1′ LWL = 7.2 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
18.4
Powerful cruiser/racer — quick in light air, reef early when it pipes up.
Ballast / Displacement
46.7%
Race-oriented ballast ratio — very stiff and powerful.
Displacement / Length
163
Moderate — a good balance of speed and load-carrying ability.
Comfort Ratio
19.0
Quick, snappy motion — better for day sails and racing than long passages.
Capsize Screening
2.07
Above the 2.0 offshore threshold — best suited for coastal and protected waters.
Hull Speed
7.2kts
S# (Speed Number)
3.4
Pounds/Inch Immersion
7lbs
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
19.0
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
2.07
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

PHRF Fleet Position

Where the Defender 35 sits on the PHRF handicap spectrum — lower numbers mean faster boats.

Racer 0–90
Cruiser/Racer 90–150
Cruiser 150–210
Dufour 35 120s/nm
Maxi 108 147s/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° 3.0 3.8 4.2 4.4
Close Reach60° 3.6 4.6 5.1 5.3
Beam Reach90° 4.4 5.6 6.3 6.8
Broad Reach120–135° 4.1 5.2 5.8 6.3
Run150–180° 3.3 4.1 4.6 4.8
These are simplified estimates based on hull speed (7.2 kts), SA/D (18.4), 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 Defender 35 — based on sail area, ballast, and displacement characteristics.

Ghost
Sweet Spot
Reef
Heavy
0–6 kts 6–20 kts 20–30 kts 30+ kts
Ghosting
0–6 kts
Light air, motor-sailing likely. Need patience and a light genoa.
Sweet Spot
6–20 kts
Comfortable under full sail. Best speed-to-comfort ratio.
Time to Reef
20–30 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 Defender 35.

Defender 35 Dufour 35 First 35 Beneteau Maxi 108 Nicholson 35 1 Rustler 36
Dimensions
LOA 35.3 35.3 35.2 35.3 35.3 35.3
LWL 29.1 27.8 28.8 29.9 26.8 26.9
Beam 10.8 11.3 12.2 11.2 10.4 11.0
Displacement 8 13 10 14 15 16
Ballast 4 5 4 5 7 7
Sail Area 495 551 555 609 698 693
Performance
PHRF 120 147
SA/Disp 18.4 15.3 18.6 16.6 17.9 17.0
Bal/Disp 46.7 41.6 46.3 46.9 45.3
Comfort 19.0 28.2 18.9 28.3 36.4 36.2
Capsize 2.07 1.89 2.23 1.84 1.67 1.72
Hull Speed 7.2 7.1 7.2 7.3 6.9 7.0