Rigging Dimensions
The four foretriangle measurements sailmakers need to quote a new suit.
I ?
18.16 ft
J ?
6.16 ft
P ?
17.33 ft
E ?
7.75 ft
Sail Area Breakdown
Calculated from rigging dimensions. Use these as your starting point when ordering a new suit.
| Sail | Area (ft²) | Area (m²) |
|---|---|---|
| MainsailP × E ÷ 2 | 67.2 | 6.2 |
| 100% ForetriangleI × J ÷ 2 | 55.9 | 5.2 |
| 150% GenoaTypical light-air headsail | 83.9 | 7.8 |
| Storm Jib~50% of foretriangle, high-cut | 28.0 | 2.6 |
| Symmetric SpinnakerEstimated from I, J | 201.4 | 18.7 |
| Total Working Sail AreaMain + 100% foretriangle | 123.1 | 11.4 |
Foretriangle Diagram
Drawn to scale from published I, J, P, E measurements — Fractional Sloop · Sovereign Design Group design
Performance Ratios
How the Sovereign 18 carries its sail relative to its displacement.
SA/D Ratio
16.1
Moderate — comfortable coastal cruiser, not overcanvassed.
Mast Height (above DWL)
24.0 ft
Clears the 65 ft ICW fixed-bridge standard with room to spare.
Ballast Ratio
40%
Stiff enough to carry a 150% genoa comfortably into moderate breeze.
Typical Sail Inventory
What Sovereign 18 owners usually carry and what's worth buying used vs. new.
Mainsail 67.2 ft²
Dacron cross-cut with 2 reef points is standard. Full-batten is a common upgrade.
Replace new
150% Genoa 83.9 ft²
The workhorse headsail. Most boats have one on a furler by now.
Replace new
110% Working Jib ~62 ft²
Good secondary sail for breezy days — used market is strong.
Buy used
Storm Jib 28.0 ft²
Bright orange recommended. Rarely used, hard to justify new.
Buy used
Asymmetric Spinnaker ~201 ft²
Popular downwind upgrade — easier than symmetric for shorthanded sailing.
Optional
Replacement Cost Estimator
Get a rough price range for a new mainsail and genoa for the Sovereign 18 — Dacron, laminate, and cruising performance tiers.