Rigging Dimensions
The four foretriangle measurements sailmakers need to quote a new suit.
I ?
41.00 ft
J ?
12.70 ft
P ?
38.00 ft
E ?
16.00 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 | 304.0 | 28.2 |
| 100% ForetriangleI × J ÷ 2 | 260.4 | 24.2 |
| 150% GenoaTypical light-air headsail | 390.5 | 36.3 |
| Storm Jib~50% of foretriangle, high-cut | 130.2 | 12.1 |
| Symmetric SpinnakerEstimated from I, J | 937.3 | 87.1 |
| Total Working Sail AreaMain + 100% foretriangle | 564.4 | 52.4 |
Foretriangle Diagram
Drawn to scale from published I, J, P, E measurements — Masthead Ketch · Ernest Tucker design
Performance Ratios
How the Dickerson 40 carries its sail relative to its displacement.
SA/D Ratio
14.0
Moderate — comfortable coastal cruiser, not overcanvassed.
Mast Height (above DWL)
— ft
Air draft not published — measure yours before any bridge transit.
Ballast Ratio
31%
Typical cruising ballast — balanced stability underway.
Typical Sail Inventory
What Dickerson 40 owners usually carry and what's worth buying used vs. new.
Mainsail 304.0 ft²
Dacron cross-cut with 2 reef points is standard. Full-batten is a common upgrade.
Replace new
150% Genoa 390.5 ft²
The workhorse headsail. Most boats have one on a furler by now.
Replace new
110% Working Jib ~286 ft²
Good secondary sail for breezy days — used market is strong.
Buy used
Storm Jib 130.2 ft²
Bright orange recommended. Rarely used, hard to justify new.
Buy used
Asymmetric Spinnaker ~937 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 Dickerson 40 — Dacron, laminate, and cruising performance tiers.