Rigging Dimensions
The four foretriangle measurements sailmakers need to quote a new suit.
I ?
98.43 ft
J ?
29.72 ft
P ?
95.14 ft
E ?
31.50 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 | 1,498.5 | 139.2 |
| 100% ForetriangleI × J ÷ 2 | 1,462.7 | 135.9 |
| 150% GenoaTypical light-air headsail | 2,194.0 | 203.8 |
| Storm Jib~50% of foretriangle, high-cut | 731.3 | 67.9 |
| Symmetric SpinnakerEstimated from I, J | 5,265.6 | 489.2 |
| Total Working Sail AreaMain + 100% foretriangle | 2,961.1 | 275.1 |
Foretriangle Diagram
Drawn to scale from published I, J, P, E measurements — Solent · Philippe Briand design
Performance Ratios
How the Cnb 78 carries its sail relative to its displacement.
SA/D Ratio
23.6
Performance-oriented — carries a lot of sail for its weight.
Mast Height (above DWL)
111.6 ft
Air draft exceeds the 65 ft ICW standard — plan accordingly.
Ballast Ratio
26%
Light ballast — tends to be tender; reef earlier.
Typical Sail Inventory
What Cnb 78 owners usually carry and what's worth buying used vs. new.
Mainsail 1,498.5 ft²
Dacron cross-cut with 2 reef points is standard. Full-batten is a common upgrade.
Replace new
150% Genoa 2,194.0 ft²
The workhorse headsail. Most boats have one on a furler by now.
Replace new
110% Working Jib ~1,609 ft²
Good secondary sail for breezy days — used market is strong.
Buy used
Storm Jib 731.3 ft²
Bright orange recommended. Rarely used, hard to justify new.
Buy used
Asymmetric Spinnaker ~5,266 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 Cnb 78 — Dacron, laminate, and cruising performance tiers.