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Performance

J9 Performance

How the J9 performs on the water — racing handicap, sail-carrying power, stability and comfort.

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The J9 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.

6.8 kts
A displacement hull pushes a bow wave whose speed is limited by the waterline length. With a waterline of 25.4′, the J9 tops out around 6.8 knots in displacement mode — after that, the bow wave outruns the hull and resistance climbs steeply.
1.34 × √25.4′ LWL = 6.8 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
27.5
Performance-oriented — carries a lot of canvas for its weight.
Displacement / Length
116
Ultralight — responsive and fast, but carries less stores.
Comfort Ratio
14.3
Quick, snappy motion — better for day sails and racing than long passages.
Capsize Screening
2.13
Above the 2.0 offshore threshold — best suited for coastal and protected waters.
Hull Speed
6.8kts
Pounds/Inch Immersion
781lbs
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
14.3
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
2.13
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 J9 sits on the PHRF handicap spectrum — lower numbers mean faster boats.

Cruiser/Racer 90–150
Cruiser 150–210
Heavy Cruiser 210–300
Hunter 28.5 180s/nm
Precision 28 207s/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° 3.2 4.0 4.5 4.7
Close Reach60° 3.8 4.9 5.4 5.7
Beam Reach90° 4.7 6.0 6.7 7.2
Broad Reach120–135° 4.4 5.5 6.2 6.7
Run150–180° 3.5 4.4 4.9 5.1
These are simplified estimates based on hull speed (6.8 kts), SA/D (27.5), 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 J9 — based on sail area, ballast, and displacement characteristics.

Ghost
Sweet Spot
Reef
Heavy
0–5 kts 5–16 kts 16–24 kts 24+ kts
Ghosting
0–5 kts
Light air, motor-sailing likely. Need patience and a light genoa.
Sweet Spot
5–16 kts
Comfortable under full sail. Best speed-to-comfort ratio.
Time to Reef
16–24 kts
Time to shorten sail. Reef the main, swap to a working jib.
Heavy Weather
24+ 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 J9.

J9 Ericson 28 2 Freedom 27 Hunter 28.5 Precision 28 Tes 28 Magnam
Dimensions
LOA 28.0 28.0 28.0 28.0 28.0 28.0
LWL 25.4 23.3 24.8 23.0 26.0
Beam 8.6 10.0 8.7 10.0 9.9
Displacement 4 7 5 5 6
Ballast 3 1 1 1
Sail Area 449 411 380
Performance
PHRF 180 207
SA/Disp 27.5 17.2 17.7
Bal/Disp 21.8 34.6
Comfort 14.3 21.8 18.6 17.5
Capsize 2.13 2.05 1.97 2.14
Hull Speed 6.8 6.5 6.7 6.8