Armstrong S1 (Step 1) S1 1850 hydrofoil front wing: 1,850 cm², 965 mm span, aspect ratio 5.00, with its closest equivalents from other brands within ±5% area and ±8% aspect ratio. Figures from Armstrong'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 |
|---|---|---|---|---|---|---|---|
| North | Sonar MA1850v2 MA1850v2 | 1,850 | +0.0% | 5.00 | +0.0% | 960 | C1 Low aspect |
| F-One | GRAVITY FCT GRAVITY FCT 1800 | 1,800 | -2.7% | 5.00 | +0.0% | 950 | C1 Low aspect |
| Slingshot | One-Lock Ease 1850 | 1,850 | +0.0% | 5.40 | +8.0% | 990 | C1 Low aspect |
| F-One | GRAVITY Carbon GRAVITY CARBON 1800 | 1,800 | -2.7% | 4.60 | -8.0% | 900 | C1 Low aspect |
| Family | S1 |
|---|---|
| Size | S1 1850 |
| Area, cm² | 1,850 |
| Area basis | unknown |
| Span, mm | 965 |
| Chord, mm | — |
| Aspect ratio | 5.00 |
| Band | C1 Low aspect |
| Brand files it under | Entry |
| Disciplines | wing, prone |
| Construction | carbon |
| Model year | 2025-2026 |
| 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 Armstrong 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.