The Dragonfly 36 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.
A displacement hull pushes a bow wave whose speed is limited by the waterline length.
With a waterline of 35.8′, the Dragonfly 36 tops out around 8.0 knots in displacement mode — after that, the bow wave outruns the hull and resistance climbs steeply.
1.34 × √35.8′ LWL = 8.0 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
28.1
Performance-oriented — carries a lot of canvas for its weight.
Displacement / Length
129
Ultralight — responsive and fast, but carries less stores.
Comfort Ratio
7.0
Quick, snappy motion — better for day sails and racing than long passages.
Capsize Screening
4.51
Above the 2.0 offshore threshold — best suited for coastal and protected waters.
Pounds/Inch Immersion
20lbs
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
7.0
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
4.51
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
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° |
3.8 |
4.8 |
5.3 |
5.6 |
| Close Reach60° |
4.6 |
5.8 |
6.4 |
6.7 |
| Beam Reach90° |
5.6 |
7.1 |
7.9 |
8.6 |
| Broad Reach120–135° |
5.2 |
6.5 |
7.3 |
7.9 |
| Run150–180° |
4.1 |
5.2 |
5.8 |
6.1 |
These are simplified estimates based on hull speed (8.0 kts),
SA/D (28.1), 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 Dragonfly 36 — 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.