Rigging Dimensions
The four foretriangle measurements sailmakers need to quote a new suit.
I ?
31.17 ft
J ?
10.17 ft
P ?
32.81 ft
E ?
13.25 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 | 217.4 | 20.2 |
| 100% ForetriangleI × J ÷ 2 | 158.5 | 14.7 |
| 150% GenoaTypical light-air headsail | 237.7 | 22.1 |
| Storm Jib~50% of foretriangle, high-cut | 79.2 | 7.4 |
| Symmetric SpinnakerEstimated from I, J | 570.6 | 53.0 |
| Total Working Sail AreaMain + 100% foretriangle | 375.9 | 34.9 |
Foretriangle Diagram
Drawn to scale from published I, J, P, E measurements — Fractional Sloop · Tony Castro design
Performance Ratios
How the Cork 1720 carries its sail relative to its displacement.
SA/D Ratio
27.6
Performance-oriented — carries a lot of sail for its weight.
Mast Height (above DWL)
— ft
Air draft not published — measure yours before any bridge transit.
Ballast Ratio
46%
Race-oriented ballast ratio — stiff and powerful.
Typical Sail Inventory
What Cork 1720 owners usually carry and what's worth buying used vs. new.
Mainsail 217.4 ft²
Dacron cross-cut with 2 reef points is standard. Full-batten is a common upgrade.
Replace new
150% Genoa 237.7 ft²
The workhorse headsail. Most boats have one on a furler by now.
Replace new
110% Working Jib ~174 ft²
Good secondary sail for breezy days — used market is strong.
Buy used
Storm Jib 79.2 ft²
Bright orange recommended. Rarely used, hard to justify new.
Buy used
Asymmetric Spinnaker ~571 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 Cork 1720 — Dacron, laminate, and cruising performance tiers.