Piper J-3 Cub — a rectangular wing that worksvsMIT Daedalus 88 — the 34 m human-powered wing
root section usa35b → dae11 · tip section — → dae31 · aspect ratio 6.945 → 36.667 · span 10730 mm → 34100 mm · area 16577850 mm² → 31712462 mm² · tip chord 1545 mm → 762 mm
units
These analyses are not directly comparable
- different trim loads (5396 N vs 1020 N) — each wing is carrying a different weight
The geometry comparison below is unaffected — it is a comparison of shapes, not of runs.
- Piper J-3 Cub — a rectangular wing that works
- MIT Daedalus 88 — the 34 m human-powered wing
What changed
| Property | Piper J-3 Cub | MIT Daedalus 88 | Change | % |
|---|---|---|---|---|
| Geometry | ||||
| Span | 10730 mm | 34100 mm | +23370 mm | +217.8% |
| Root chord | 1545 mm | 1050 mm | -495 mm | -32.0% |
| Tip chord | 1545 mm | 762 mm | -783 mm | -50.7% |
| Sweep parameter | 0.000 | 0.484 | +0.484 | — |
| Tip twist | 0.00° | -1.50° | -1.50° | — |
| TE thickness | 3 mm | 2 mm | -2 mm | -50.0% |
| Tip cap reach | 0.300 | 0.250 | -0.050 | -16.7% |
| Derived | ||||
| Aspect ratio | 6.945 | 36.667 | +29.722 | +428.0% |
| Area | 16577850 mm² | 31712462 mm² | +15134612 mm² | +91.3% |
| Taper | 1.000 | 0.726 | -0.274 | -27.4% |
| MAC | 1545 mm | 939 mm | -606 mm | -39.2% |
| Sections | ||||
| Root section | usa35b | dae11 | changed | — |
| Tip section | — | dae31 | changed | — |
| Shapedeviation at matched span fractions, 64 samples | ||||
| Chord deviation (max) | 783 mm | |||
| Chord deviation (RMS) | 622 mm | |||
| Twist deviation (max) | 1.50° | |||
| Dihedral deviation (max) | 204 mm | |||
| Tip cap deviation (max) | 11707 mm | |||
Performance
CoefficientsDimensionless — how good the shape is, independent of size and speed.
Spanwise
withheld — “Piper J-3 Cub” integrates to CL 0.002 against the polar’s CL at the same α (this analysis predates the loading reporting its own) 0.330 (0.01×); “MIT Daedalus 88” integrates to CL 0.120 against the polar’s CL at the same α (this analysis predates the loading reporting its own) 0.913 (0.13×). A loading that does not integrate back to its own wing’s CL is not a coarse curve, it is a wrong one.
air, ρ = 1.225 kg/m³
data
| CD | Piper J-3 Cub | MIT Daedalus 88 |
|---|---|---|
| 0.012 | 0.326 | 0.444 |
| 0.013 | 0.330 | 0.461 |
| 0.013 | 0.336 | 0.492 |
| 0.013 | 0.349 | 0.549 |
| 0.014 | 0.364 | 0.616 |
| 0.015 | 0.378 | 0.672 |
| 0.015 | 0.383 | 0.697 |
| 0.016 | 0.410 | 0.794 |
| 0.017 | 0.437 | 0.858 |
| 0.019 | 0.457 | 0.913 |
| 0.021 | 0.511 | 1.02 |
| 0.023 | 0.529 | 1.06 |
| 0.027 | 0.605 | 1.20 |
| 0.029 | 0.627 | 1.25 |
| 0.036 | 0.729 | 1.42 |
| 0.039 | 0.759 | 1.49 |