Asymmetric
Asymmetric Spinnakers
Section titled “Asymmetric Spinnakers”Technical specifications for asymmetric spinnaker types A1-A4 and gennakers.
Type Classification
Section titled “Type Classification”Asymmetric Comparison Table
Section titled “Asymmetric Comparison Table”| Type | Wind Range | Apparent Angle | Cloth Weight | Shape | Characteristics |
|---|---|---|---|---|---|
| A1 (Light Air Runner) | 0-8 kts | 70-180° | 0.4-0.5oz nylon | Full, max volume | Ultra-light, max draft, requires expert handling |
| A2 (All-Purpose) | 8-20 kts | 80-165° | 0.75oz nylon | Moderate fullness | Most versatile, standard cruising, handles varying conditions |
| A3 (Reaching) | 12-25 kts | 60-120° | 0.75-1.5oz nylon | Flatter, tighter luff | Higher angles, reduced heeling, Code Zero alternative |
| A4 (Heavy Air Runner) | 20-30+ kts | 90-180° | 1.5-2.2oz nylon | Flat, controlled draft | Storm conditions, max control, reduced oscillation |
Gennaker Specifications
Section titled “Gennaker Specifications”| Property | Specification |
|---|---|
| Wind range | 8-22 knots |
| Apparent angle | 50-140° |
| Cloth weight | 0.75oz nylon or laminate |
| Shape | Flatter than A2, tighter luff |
| Tack location | Fixed bowsprit or deck fitting |
Applications: Cruiser-racer, point-to-point, reaching
Construction
Section titled “Construction”Panel Layout
Section titled “Panel Layout”All asymmetric spinnakers use radial-cut construction with panels radiating from corners to optimize load distribution and shape retention.
Corner Hardware
Section titled “Corner Hardware”Corner Ring Specifications
Section titled “Corner Ring Specifications”Stainless steel pressed rings at head, tack, and clew corners.
| Sail Area | Ring Size | Inner Diameter | Application |
|---|---|---|---|
| < 50m² | #4 | 20mm | Small asymmetrics (25-35ft) |
| 50-100m² | #5 | 25mm | Standard asymmetrics (35-45ft) |
| 100-150m² | #6 | 30mm | Large asymmetrics (45-55ft) |
| > 150m² | #7-#8 | 35-40mm | Maxi yachts (55ft+) |
Construction:
- Webbed ring installation (more durable than pressed)
- Dacron reinforcement patches underneath
- Radial corner tapes for load distribution
Sizing Guidelines
Section titled “Sizing Guidelines”Area Calculation
Section titled “Area Calculation”| Method | Formula |
|---|---|
| Sail area ratio | Spinnaker area = 1.5-2.0 × I × J |
| Racing maximums | Per IRC/ORC rating rules |
| Cruising typical | 1.3-1.6 × I × J |
Dimensional Parameters
Section titled “Dimensional Parameters”| Parameter | Description |
|---|---|
| SLU | Spinnaker luff (tack to head) |
| SLE | Spinnaker leech (clew to head) |
| SF | Spinnaker foot (tack to clew) |
| SMW | Spinnaker max width (half-height) |