J/145
J/Boats · Rod Johnstone · 2000
Updated
The J/145 is a 14.63 m semi-displacement racing yacht designed by Rod Johnstone and built by J/Boats, first launched in 2000. It races in Class A. Across the measured fleet it goes better than its own numbers promise, ahead of 89% 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 89% of the boats it races against.
6th of 46 in its class.
Length
14.63 m
48′ 0″
Beam
3.97 m
Draft
2.73 m
Displacement
9.3 t
Sail area
149 m²
On the podium
Where a J/145 finishes when she goes racing.
Not enough data yet to show how this design finishes. It has not been found in the race results we have collected so far.
Recent regattas
The latest events where a J/145 was on the start line, named as the organisers publish them.
No regattas found yet.
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
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Not enough data yet: no races of 10 NM or less carry a published distance.
Offshore & coastal
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Not enough data yet: no races over 10 NM carry a published distance.
Who she races against
The designs a J/145 actually lines up with, most often first. The bar shows how those meetings ended.
Not enough data yet to say who this design races against. No result we have collected puts it on the water beside another design we track.
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
6.45
36°
Beam reach
10.09
90°
Broad reach
12.55
135°
Downwind VMG
9.93
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.
There is no obvious weak spot here. It rewards preparation and crew work more than it rewards picking the right day.
Where it gains
Its best ground is on the run in a strong breeze, where it outruns what it looks like on paper, and by a margin worth having. It holds that advantage on the beat as well, so the gain is not down to one leg of the course.
Where it pays
It falls short on the beam when it blows, giving away time it never gets back. That is a hull that will lift and run given enough breeze.
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 J/145
Boat speed in knots, by true wind angle and wind strength.
| Angle | 6 kn | 10 kn | 14 kn | 20 kn |
|---|---|---|---|---|
| Beat VMG | 4.47 | 5.86 | 6.22 | 6.45 |
| 52° | 6.82 | 8.33 | 8.62 | 8.82 |
| 60° | 7.19 | 8.55 | 8.85 | 9.09 |
| 75° | 7.45 | 8.76 | 9.18 | 9.56 |
| 90° | 7.38 | 8.81 | 9.46 | 10.09 |
| 110° | 7.02 | 8.90 | 9.69 | 10.71 |
| 120° | 6.86 | 8.97 | 9.96 | 11.26 |
| 135° | 6.15 | 8.68 | 9.99 | 12.55 |
| 150° | 5.15 | 7.74 | 9.21 | 11.46 |
| Run VMG | 4.46 | 6.70 | 8.02 | 9.93 |
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 1110 kg.
Rigging
J/145 rig and sail dimensions
A J/145 carries 17.76 m of mainsail hoist on a 6.25 m boom, a forestay 19.20 m above the deck and a 8.10 m bowsprit. Typical figures across the 4 boats measured under the current VPP, with the range each one spans.
Rig
Sails