The Lagoon 620 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 59.8′, the Lagoon 620 tops out around 10.4 knots in displacement mode — after that, the bow wave outruns the hull and resistance climbs steeply.
1.34 × √59.8′ LWL = 10.4 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
22.4
Performance-oriented — carries a lot of canvas for its weight.
Displacement / Length
149
Ultralight — responsive and fast, but carries less stores.
Comfort Ratio
17.2
Quick, snappy motion — better for day sails and racing than long passages.
Capsize Screening
3.17
Above the 2.0 offshore threshold — best suited for coastal and protected waters.
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
17.2
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
3.17
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° |
4.8 |
6.0 |
6.7 |
7.0 |
| Close Reach60° |
5.8 |
7.3 |
8.1 |
8.5 |
| Beam Reach90° |
7.1 |
8.9 |
10.0 |
10.8 |
| Broad Reach120–135° |
6.5 |
8.2 |
9.2 |
10.0 |
| Run150–180° |
5.2 |
6.6 |
7.4 |
7.7 |
These are simplified estimates based on hull speed (10.4 kts),
SA/D (22.4), 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 Lagoon 620 — 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 Lagoon 620.
|
Lagoon 620 |
Aura 51 |
Lagoon 50 |
Outremer 55 |
Privilege 585 |
| Dimensions |
| LOA |
62.0 |
51.0 |
48.4 |
54.8 |
55.8 |
| LWL |
59.8 |
— |
46.9 |
— |
55.0 |
| Beam |
32.8 |
26.5 |
26.6 |
27.2 |
30.3 |
| Displacement |
71 |
39 |
45 |
29 |
39,200 |
| Sail Area |
2,400 |
1 |
1,701 |
1 |
— |
| Performance |
| SA/Disp |
22.4 |
22.8 |
21.2 |
27.3 |
— |
| Comfort |
17.2 |
17.0 |
18.8 |
— |
11.6 |
| Capsize |
3.17 |
3.11 |
2.97 |
3.51 |
3.57 |
| Hull Speed |
10.4 |
8.8 |
9.2 |
— |
9.9 |