Bonin 31
Bonin · Maurizio Cossutti · 2006
Updated
The Bonin 31 is a 9.39 m displacement racing yacht designed by Maurizio Cossutti and built by Bonin, first launched in 2006. It races in Class C.
Length
9.39 m
30′ 10″
Beam
3.34 m
Draft
1.95 m
Displacement
3.0 t
Sail area
55 m²
On the podium
Where a Bonin 31 finishes when she goes racing.
On the podium
0%
of 26 starts by 2 boats
Wins
0%
Read from 26 starts by 2 boats between 2023 and 2026, counting races with six boats or more.
Recent regattas
The latest events where a Bonin 31 was on the start line, named as the organisers publish them.
151 Miglia - Trofeo Cetilar2026- Campionato Nazionale d'Area - Isole Sicilia e Sardegna2026
- Coppa Regina dei Paesi Bassi2026
- 49° Campionato Invernale Vela d'Altura2026
- Campionato Invernale del Sabato2025
Raced one we are missing?
Report a regattaRound the buoys, or offshore
A short windward-leeward and a night at sea ask different things of a boat. Here is how this one does in each.
Round the buoys
0%
of these races end on the podium
Offshore & coastal
0%
of these races end on the podium
Level across both. Plenty of designs fall away once the course gets long — a light hull that thrives round the cans can struggle through a night at sea. This one does not.
Who she races against
The designs a Bonin 31 actually lines up with, most often first. The bar shows how those meetings ended.
Also met, too few times for a figure:
Dufour 34 (7 meetings), Oceanis 46.1 (7 meetings), Sun Odyssey 45.2 (7 meetings), Grand Soleil 40 (Polli) (7 meetings), Comet 51 (7 meetings), Comet 38 (Vallicelli) (6 meetings), Grand Soleil 43 (Maletto) (6 meetings), Grand Soleil 47 (7 meetings), JOD 35 (6 meetings), Solaris 55 (5 meetings), Pogo 50 (5 meetings), Grand Soleil 46 (Carkeek) (5 meetings), Rimar 44.3 (4 meetings), Cobra 33 (4 meetings), J/122 (4 meetings), J/109 (4 meetings), Dufour 455 (4 meetings), Dehler 42 (4 meetings), Swan 47 (4 meetings), First 41 (4 meetings), Elan 410 (4 meetings)
Some of the boats it races against
How the Bonin 31 has fared against each of them, boat against boat on corrected time. Ordered by how often the two meet, not by who wins.
Speed at every angle
The shape of this design's speed, drawn from the measured fleet. Pick a wind and watch it stretch.
Upwind VMG
5.09
38°
Beam reach
8.39
90°
Broad reach
10.07
135°
Downwind VMG
7.78
170°
Speed in knots at 20 knots of true wind. Green marks the angles that pay: the closest useful beat and the deepest run worth sailing.
Where it wins and where it pays
Every boat is judged against its own measurements — length, weight, sail area. The quicker those say it should be, the more it has to deliver just to break even. Going fast is not enough: it has to go faster than its own numbers promised.
This is a boat that wants breeze. Give it a fresh day and long legs and it delivers more than it promised; in a drifter it is working uphill.
Where it gains
Its best ground is off the wind in a strong breeze, where it goes better than its measurements say it should, and by a margin worth having. It holds that advantage running deep as well, so the gain is not down to one leg of the course.
Where it pays
It falls short upwind in a strong breeze, giving away time it never gets back. That is a displacement hull working to its designed speed.
Above the line it delivers more than promised and gains on the fleet. Below, it falls short. Move the wind: plenty of boats sit on one side in the light and the other when it blows.
Full width is 1.0 kn either way.
At 10 knots this design makes back more than its rating asks on the upwind.
How fast is a Bonin 31
Boat speed in knots, by true wind angle and wind strength.
| Angle | 6 kn | 10 kn | 14 kn | 20 kn |
|---|---|---|---|---|
| Beat VMG | 3.50 | 4.71 | 5.05 | 5.09 |
| 52° | 5.34 | 6.70 | 7.06 | 7.16 |
| 60° | 5.62 | 6.85 | 7.27 | 7.43 |
| 75° | 5.83 | 6.99 | 7.54 | 7.90 |
| 90° | 5.89 | 7.17 | 7.70 | 8.39 |
| 110° | 5.87 | 7.35 | 8.12 | 9.08 |
| 120° | 5.74 | 7.29 | 8.26 | 9.50 |
| 135° | 5.16 | 6.98 | 7.96 | 10.07 |
| 150° | 4.35 | 6.36 | 7.36 | 8.90 |
| Run VMG | 3.77 | 5.51 | 6.56 | 7.78 |
How they are set up
The range each sail spans across the fleet.
Roughly half carry a folding propeller. Crew weight is declared around 540 kg.
Rigging
Bonin 31 rig and sail dimensions
A Bonin 31 carries 11.83 m of mainsail hoist on a 4.05 m boom, a forestay 12.38 m above the deck and a 4.70 m bowsprit. Typical figures across the 4 boats measured under the current VPP, with the range each one spans.
Rig
Sails
The spinnaker spreads widest of all — 83 to 91 m² depending on bowsprit and set-up. Before ordering a sail, read the figure on your own measurement record rather than the typical one for the design.