X4.3
X-Yachts · Niels Jeppesen · 2016
Updated
The X4.3 is a 12.49 m displacement racing yacht designed by Niels Jeppesen and built by X-Yachts, first launched in 2016. It races in Class B. Across the measured fleet it goes better than its own numbers promise, ahead of 84% of the designs it races against. It is at its best in light air and struggles to hold that once it blows.
Goes better than its own measurements promise, and does it better than 84% of the boats it races against.
16th of 92 in its class.
This design has been found in real race results — 3 starts across 3 events — not only in measurement files.
Length
12.49 m
41′ 0″
Beam
3.96 m
Draft
2.23 m
Displacement
9.7 t
Sail area
99 m²
On the podium
Where a X4.3 finishes when she goes racing.
0
Wins
0
Seconds
0
Thirds
3
Starts
Not enough races yet for a percentage — these are the counts so far. We keep collecting results, so this will fill in.
Read from 3 starts by 3 boats between 2023 and 2026, counting races with six boats or more.
Recent regattas
The latest events where a X4.3 was on the start line, named as the organisers publish them.
Graf-Zeppelin-Regatta2026
Regata Jabuka2024
50 Mijl Doublehanded2023
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
—
Not enough data yet: no races of 10 NM or less carry a published distance.
Offshore & coastal
—
Not enough data yet: 1 race over 10 NM carry a published distance.
Who she races against
The designs a X4.3 actually lines up with, most often first. The bar shows how those meetings ended.
Met too few times for a figure:
J/122 (3 meetings), Dehler 41 (Judel/Vrolijk) (1 meeting), Maxfun 35 (1 meeting), Elan 400 (1 meeting), Psaros 33 (2 meetings), Elan 31 (Design) (1 meeting), More 40 (1 meeting), Grand Soleil 37 (Carkeek) (1 meeting), Hanse 400 (1 meeting), Sun Fast 3600 (1 meeting)
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
5.58
39°
Beam reach
9.07
90°
Broad reach
10.29
135°
Downwind VMG
8.27
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.
It does its best work before the breeze fills in. Early-season racing and morning breezes play to its strengths; once it pipes up the fleet comes back to it.
Where it gains
Its best ground is on a broad reach in light air, where it outruns what it looks like on paper, and by a margin worth having. It holds that advantage across the wind as well, so the gain is not down to one leg of the course.
Where it pays
It falls short running deep when it blows, 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 0.4 kn either way.
At 10 knots this design makes back more than its rating asks on the broad reach.
How fast is a X4.3
Boat speed in knots, by true wind angle and wind strength.
| Angle | 6 kn | 10 kn | 14 kn | 20 kn |
|---|---|---|---|---|
| Beat VMG | 3.65 | 4.93 | 5.44 | 5.58 |
| 52° | 5.60 | 7.27 | 7.81 | 8.00 |
| 60° | 5.92 | 7.54 | 8.05 | 8.25 |
| 75° | 6.27 | 7.77 | 8.31 | 8.68 |
| 90° | 6.36 | 7.96 | 8.54 | 9.07 |
| 110° | 6.31 | 8.14 | 8.91 | 9.64 |
| 120° | 6.18 | 8.09 | 9.00 | 10.03 |
| 135° | 5.53 | 7.75 | 8.75 | 10.29 |
| 150° | 4.66 | 6.92 | 8.18 | 9.41 |
| Run VMG | 4.03 | 5.99 | 7.18 | 8.27 |
How they are set up
The range each sail spans across the fleet.
Nearly all carry a folding propeller. A bowsprit is standard across the fleet. Crew weight is declared around 760 kg.
Rigging
X4.3 rig and sail dimensions
A X4.3 carries 16.34 m of mainsail hoist on a 5.70 m boom, a forestay 17.42 m above the deck and a 5.64 m bowsprit. Typical figures across the 22 boats measured under the current VPP, with the range each one spans.
Rig
Sails
The spinnaker spreads widest of all — 127 to 193 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.