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Performance

Flax 27 Performance

How the Flax 27 performs on the water — racing handicap, sail-carrying power, stability and comfort.

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The Flax 27 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.

6.4 kts
A displacement hull pushes a bow wave whose speed is limited by the waterline length. With a waterline of 22.6′, the Flax 27 tops out around 6.4 knots in displacement mode — after that, the bow wave outruns the hull and resistance climbs steeply.
1.34 × √22.6′ LWL = 6.4 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
26.8
Performance-oriented — carries a lot of canvas for its weight.
Ballast / Displacement
28.0%
Light ballast — tends to be tender; reef earlier than the numbers suggest.
Displacement / Length
106
Ultralight — responsive and fast, but carries less stores.
Comfort Ratio
12.4
Quick, snappy motion — better for day sails and racing than long passages.
Capsize Screening
2.11
Above the 2.0 offshore threshold — best suited for coastal and protected waters.
Hull Speed
6.4kts
S# (Speed Number)
5.2
SA/Disp (Calculated)
24.1
Computed from measured I/J/P/E rather than reported sail area.
Pounds/Inch Immersion
4lbs
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
12.4
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
2.11
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 Flax 27 sits on the PHRF handicap spectrum — lower numbers mean faster boats.

Cruiser/Racer 90–150
Cruiser 150–210
Heavy Cruiser 210–300
Cs 27 204s/nm
Pearson 27 204s/nm
Catalina 27 207s/nm
Precision 27 222s/nm
Tartan 27 234s/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 5.4
Beam Reach90° 4.5 5.6 6.3 6.8
Broad Reach120–135° 4.1 5.2 5.8 6.3
Run150–180° 3.3 4.2 4.7 4.9
These are simplified estimates based on hull speed (6.4 kts), SA/D (26.8), 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 Flax 27 — based on sail area, ballast, and displacement characteristics.

Ghost
Sweet Spot
Reef
Heavy
0–5 kts 5–14 kts 14–22 kts 22+ kts
Ghosting
0–5 kts
Light air, motor-sailing likely. Need patience and a light genoa.
Sweet Spot
5–14 kts
Comfortable under full sail. Best speed-to-comfort ratio.
Time to Reef
14–22 kts
Time to shorten sail. Reef the main, swap to a working jib.
Heavy Weather
22+ 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 Flax 27.

Flax 27 Catalina 27 Cs 27 Pearson 27 Precision 27 Tartan 27
Dimensions
LOA 26.9 26.9 27.0 26.9 27.0 27.0
LWL 22.6 23.0 23.9 22.5 22.8 21.4
Beam 7.4 9.2 9.3 9.2 10.0 8.6
Displacement 2 6 6 5 5 7
Ballast 771 2 2 2 1 2
Sail Area 328 323 453 332
Performance
PHRF 207 204 204 222 234
SA/Disp 26.8 14.3 21.8 16.5
Bal/Disp 28.0 39.4 39.3 33.3 32.4
Comfort 12.4 25.0 19.4 19.7
Capsize 2.11 1.86 2.05 2.04
Hull Speed 6.4 6.3 6.6 6.4