The Oceanis 390 Beneteau is moderately powered for comfortable coastal cruising, with acceptable motion comfort for coastal passages.
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 33.1′, the Oceanis 390 Beneteau tops out around 7.7 knots in displacement mode — after that, the bow wave outruns the hull and resistance climbs steeply.
1.34 × √33.1′ LWL = 7.7 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
16.7
Moderate sail power — a capable coastal cruiser, not overpowered.
Ballast / Displacement
35.0%
Typical cruising ballast — balanced stability and motion underway.
Displacement / Length
216
Moderate — a good balance of speed and load-carrying ability.
Comfort Ratio
25.1
Acceptable coastal comfort — fine for weekends, notice the chop offshore.
Capsize Screening
2.02
Above the 2.0 offshore threshold — best suited for coastal and protected waters.
Pounds/Inch Immersion
9lbs
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
25.1
Acceptable coastal comfort — fine for weekends, notice the chop offshore.
Under 20 — Snappy, racing motion
20–30 — Acceptable coastal
30–40 — Good offshore comfort
Over 40 — Very comfortable offshore
Capsize Screening Formula
2.02
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° |
3.0 |
3.8 |
4.3 |
4.5 |
| Close Reach60° |
3.7 |
4.7 |
5.2 |
5.4 |
| Beam Reach90° |
4.5 |
5.7 |
6.4 |
6.7 |
| Broad Reach120–135° |
4.2 |
5.3 |
5.9 |
6.1 |
| Run150–180° |
3.3 |
4.2 |
4.7 |
4.9 |
These are simplified estimates based on hull speed (7.7 kts),
SA/D (16.7), 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 Oceanis 390 Beneteau — 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 Oceanis 390 Beneteau.
|
Oceanis 390 Beneteau |
Bavaria 390 |
Dufour 39 Cc |
First 407 Beneteau |
J39 |
Oceanis 393 Beneteau |
| Dimensions |
| LOA |
39.4 |
39.4 |
39.3 |
39.3 |
39.4 |
39.4 |
| LWL |
33.1 |
34.1 |
31.8 |
34.8 |
32.5 |
33.1 |
| Beam |
13.1 |
13.1 |
12.6 |
12.3 |
12.4 |
13.1 |
| Displacement |
17 |
17 |
15 |
15 |
12 |
17 |
| Ballast |
6 |
6 |
4 |
5 |
5 |
6 |
| Sail Area |
710 |
720 |
— |
806 |
799 |
720 |
| Performance |
| SA/Disp |
16.7 |
17.0 |
— |
21.1 |
23.3 |
17.3 |
| Bal/Disp |
35.0 |
36.3 |
29.0 |
39.1 |
— |
35.3 |
| Comfort |
25.1 |
24.6 |
— |
22.9 |
20.1 |
— |
| Capsize |
2.02 |
2.02 |
— |
1.99 |
2.12 |
— |
| Hull Speed |
7.7 |
7.8 |
— |
7.9 |
7.6 |
— |