North Sonar SF680 SF680 hydrofoil front wing: 680 cm², 790 mm span, aspect ratio 9.20, with its closest equivalents from other brands within ±5% area and ±8% aspect ratio. Figures from North's own published specifications.
Projected and flat area run 3–8% apart. A marked area is one whose brand does not state which it publishes, so a match inside the area tolerance may be comparing unlike figures.
| Brand | Wing | Area cm² | Δ area | Aspect ratio | Δ AR | Span mm | Band |
|---|---|---|---|---|---|---|---|
| Duotone | Crest D/LAB 675 | 675 | -0.7% | 9.30 | +1.1% | 790 | C3 Mid aspect |
| Levitaz | Front Wing FS 680 FS 680 | 680 | +0.0% | 8.70 | -5.4% | 770 | C3 Mid aspect |
| Cabrinha | Fusion H-Series MkII H700 | 700 | +2.9% | 9.49 | +3.2% | 815 | C3 Mid aspect |
| GONG | Ypra Slalom V3 Atmo S | 700 | +2.9% | 8.90 | -3.3% | 790 | C3 Mid aspect |
| Takoon | Flash Front Wing 680 | 680 | +0.0% | 9.80 | +6.5% | 815 | C4 High aspect |
| AFS | Silk V2 Front Wing Silk 650 | 650 | -4.4% | 9.00 | -2.2% | 765 | C3 Mid aspect |
| F-One | EAGLE HM Carbon EAGLE 690 | 690 | +1.5% | 9.70 | +5.4% | 820 | C4 High aspect |
| AFS | Pure Fuselink Foil (monobloc front wing + fuselage) Pure 700 | 700 | +2.9% | 9.60 | +4.3% | 820 | C4 High aspect |
| KT Foiling | Nomad 700 Nomad 700 | 700 | +2.9% | 8.70 | -5.4% | 780 | C3 Mid aspect |
| GONG | Ypra Race V3 670 cm² | 670 | -1.5% | 9.90 | +7.6% | 820 | C4 High aspect |
| GONG | Fluid V3 Atmo XS | 710 | +4.4% | 8.70 | -5.4% | 780 | C3 Mid aspect |
| Family | Sonar SF (Surf Series) |
|---|---|
| Size | SF680 |
| Area, cm² | 680 |
| Area basis | unknown |
| Span, mm | 790 |
| Chord, mm | — |
| Aspect ratio | 9.20 |
| Band | C3 Mid aspect |
| Brand files it under | Surf / carve |
| Disciplines | prone, wing, downwind, pump, wake |
| Construction | carbon pre-preg |
| Model year | 2026 |
| Source | manufacturer |
The brand's published aspect ratio agrees with its own span and area (span² ÷ area) to within 5%, so the figure is confirmed.
See North on the plot →Data current to August 2026. Fast Bobby is the researcher, never the reviewer: every figure above is the manufacturer's published claim, converted to comparable units, and nothing here is a riding impression.