Rigging Dimensions
The four foretriangle measurements sailmakers need to quote a new suit.
I ?
25.00 ft
J ?
8.67 ft
P ?
22.50 ft
E ?
9.50 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 | 106.9 | 9.9 |
| 100% ForetriangleI × J ÷ 2 | 108.4 | 10.1 |
| 150% GenoaTypical light-air headsail | 162.6 | 15.1 |
| Storm Jib~50% of foretriangle, high-cut | 54.2 | 5.0 |
| Symmetric SpinnakerEstimated from I, J | 390.2 | 36.2 |
| Total Working Sail AreaMain + 100% foretriangle | 215.3 | 20.0 |
Foretriangle Diagram
Drawn to scale from published I, J, P, E measurements — Masthead Sloop · Robert Finch design
Performance Ratios
How the Spirit 23 carries its sail relative to its displacement.
SA/D Ratio
17.4
Moderate — comfortable coastal cruiser, not overcanvassed.
Mast Height (above DWL)
— ft
Air draft not published — measure yours before any bridge transit.
Ballast Ratio
29%
Light ballast — tends to be tender; reef earlier.
Typical Sail Inventory
What Spirit 23 owners usually carry and what's worth buying used vs. new.
Mainsail 106.9 ft²
Dacron cross-cut with 2 reef points is standard. Full-batten is a common upgrade.
Replace new
150% Genoa 162.6 ft²
The workhorse headsail. Most boats have one on a furler by now.
Replace new
110% Working Jib ~119 ft²
Good secondary sail for breezy days — used market is strong.
Buy used
Storm Jib 54.2 ft²
Bright orange recommended. Rarely used, hard to justify new.
Buy used
Asymmetric Spinnaker ~390 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 Spirit 23 — Dacron, laminate, and cruising performance tiers.