Downwind glide foil — high aspect reference front wingvsCessna 172 Skyhawk — the most-built wing in aviation
root section e818 → naca2412 · area 121109 mm² → 16463140 mm² · tip chord 48 mm → 1310 mm · te thickness 0 mm → 3 mm · mac 104 mm → 1504 mm · root chord 130 mm → 1630 mm
units
These analyses are not directly comparable
- different fluids (water-salt vs air) — density and viscosity both differ, so the drag numbers are not on the same footing
- different trim loads (932 N vs 10791 N) — each wing is carrying a different weight
The geometry comparison below is unaffected — it is a comparison of shapes, not of runs.
- Downwind glide foil — high aspect reference front wing
- Cessna 172 Skyhawk — the most-built wing in aviation
What changed
| Property | Downwind glide foil | Cessna 172 Skyhawk | Change | % |
|---|---|---|---|---|
| Geometry | ||||
| Span | 1240 mm | 11000 mm | +9760 mm | +787.1% |
| Root chord | 130 mm | 1630 mm | +1500 mm | +1153.8% |
| Tip chord | 48 mm | 1310 mm | +1262 mm | +2629.2% |
| Sweep parameter | 9.717 | 1.666 | -8.051 | -82.9% |
| Dihedral | -2.50° | 1.73° | +4.23° | -169.2% |
| Tip twist | -2.50° | -3.00° | -0.50° | +20.0% |
| TE thickness | 0 mm | 3 mm | +3 mm | +1400.0% |
| Sections | 30 | 40 | +10 | +33.3% |
| Tip cap reach | 0.400 | 0.200 | -0.200 | -50.0% |
| Derived | ||||
| Aspect ratio | 12.696 | 7.350 | -5.346 | -42.1% |
| Area | 121109 mm² | 16463140 mm² | +16342031 mm² | +13493.6% |
| Taper | 0.369 | 0.804 | +0.434 | +117.7% |
| MAC | 104 mm | 1504 mm | +1400 mm | +1343.5% |
| Sections | ||||
| Root section | e818 | naca2412 | changed | — |
| Shapedeviation at matched span fractions, 64 samples | ||||
| Chord deviation (max) | 1500 mm | |||
| Chord deviation (RMS) | 1401 mm | |||
| Twist deviation (max) | 0.50° | |||
| Dihedral deviation (max) | 193 mm | |||
| Tip cap deviation (max) | 5084 mm | |||
Performance
CoefficientsDimensionless — how good the shape is, independent of size and speed.
Spanwise
withheld — “Downwind glide foil” integrates to CL 0.061 against the polar’s CL at the same α (this analysis predates the loading reporting its own) 0.446 (0.14×); “Cessna 172 Skyhawk” integrates to CL 0.034 against the polar’s CL at the same α (this analysis predates the loading reporting its own) 0.344 (0.10×). A loading that does not integrate back to its own wing’s CL is not a coarse curve, it is a wrong one.
mixed fluids (water (sea), air)
data
| CD | Downwind glide foil | Cessna 172 Skyhawk |
|---|---|---|
| 0.006 | 0.092 | 0.148 |
| 0.007 | 0.102 | 0.151 |
| 0.007 | 0.115 | 0.155 |
| 0.007 | 0.116 | 0.156 |
| 0.007 | 0.131 | 0.160 |
| 0.007 | 0.150 | 0.169 |
| 0.007 | 0.166 | 0.178 |
| 0.007 | 0.173 | 0.181 |
| 0.008 | 0.203 | 0.200 |
| 0.008 | 0.211 | 0.206 |
| 0.008 | 0.240 | 0.226 |
| 0.008 | 0.259 | 0.241 |
| 0.009 | 0.289 | 0.262 |
| 0.010 | 0.317 | 0.285 |
| 0.011 | 0.355 | 0.312 |
| 0.012 | 0.393 | 0.344 |
| 0.013 | 0.446 | 0.380 |
| 0.015 | 0.489 | 0.422 |
| 0.019 | 0.577 | 0.489 |
| 0.021 | 0.602 | 0.529 |
| 0.032 | 0.731 | 0.685 |
| 0.035 | 0.775 | 0.724 |