Rigging Dimensions
The four foretriangle measurements sailmakers need to quote a new suit.
I ?
59.50 ft
J ?
16.50 ft
P ?
55.50 ft
E ?
19.17 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 | 532.0 | 49.4 |
| 100% ForetriangleI × J ÷ 2 | 490.9 | 45.6 |
| 150% GenoaTypical light-air headsail | 736.3 | 68.4 |
| Storm Jib~50% of foretriangle, high-cut | 245.4 | 22.8 |
| Symmetric SpinnakerEstimated from I, J | 1,767.2 | 164.2 |
| Total Working Sail AreaMain + 100% foretriangle | 1,022.8 | 95.0 |
Foretriangle Diagram
Drawn to scale from published I, J, P, E measurements — Fractional Sloop · Tim Jackett design
Performance Ratios
How the Tartan 4700 carries its sail relative to its displacement.
SA/D Ratio
17.8
Moderate — comfortable coastal cruiser, not overcanvassed.
Mast Height (above DWL)
— ft
Air draft not published — measure yours before any bridge transit.
Ballast Ratio
35%
Typical cruising ballast — balanced stability underway.
Typical Sail Inventory
What Tartan 4700 owners usually carry and what's worth buying used vs. new.
Mainsail 532.0 ft²
Dacron cross-cut with 2 reef points is standard. Full-batten is a common upgrade.
Replace new
150% Genoa 736.3 ft²
The workhorse headsail. Most boats have one on a furler by now.
Replace new
110% Working Jib ~540 ft²
Good secondary sail for breezy days — used market is strong.
Buy used
Storm Jib 245.4 ft²
Bright orange recommended. Rarely used, hard to justify new.
Buy used
Asymmetric Spinnaker ~1,767 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 Tartan 4700 — Dacron, laminate, and cruising performance tiers.