Piper J-3 Cub — a rectangular wing that worksvsPiper PA-28 Cherokee — the Hershey-bar wing
root section usa35b → naca652415 · dihedral 1.00° → 7.00° · aspect ratio 6.945 → 5.624 · span 10730 mm → 9144 mm · area 16577850 mm² → 14868144 mm² · mac 1545 mm → 1626 mm
units
These analyses are not directly comparable
- different trim loads (5396 N vs 9565 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
- Piper PA-28 Cherokee — the Hershey-bar wing
What changed
| Property | Piper J-3 Cub | Piper PA-28 Cherokee | Change | % |
|---|---|---|---|---|
| Geometry | ||||
| Span | 10730 mm | 9144 mm | -1586 mm | -14.8% |
| Root chord | 1545 mm | 1626 mm | +81 mm | +5.2% |
| Tip chord | 1545 mm | 1626 mm | +81 mm | +5.2% |
| Dihedral | 1.00° | 7.00° | +6.00° | +600.0% |
| Derived | ||||
| Aspect ratio | 6.945 | 5.624 | -1.321 | -19.0% |
| Area | 16577850 mm² | 14868144 mm² | -1709706 mm² | -10.3% |
| MAC | 1545 mm | 1626 mm | +81 mm | +5.2% |
| Sections | ||||
| Root section | usa35b | naca652415 | changed | — |
| Shapedeviation at matched span fractions, 64 samples | ||||
| Chord deviation (max) | 81 mm | |||
| Chord deviation (RMS) | 81 mm | |||
| Twist deviation (max) | 0.00° | |||
| Dihedral deviation (max) | 468 mm | |||
| Tip cap deviation (max) | 797 mm | |||
Performance
CoefficientsDimensionless — how good the shape is, independent of size and speed.
ForcesNewtons and watts — what each wing actually carries and costs at this condition.
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×); “Piper PA-28 Cherokee” integrates to CL 0.007 against the polar’s CL at the same α (this analysis predates the loading reporting its own) 0.271 (0.03×). 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
| V (kt) | Piper J-3 Cub | Piper PA-28 Cherokee |
|---|---|---|
| 59.40 | 22.81 | 11.06 |
| 62.69 | 23.78 | 12.23 |
| 67.79 | 25.06 | 14.04 |
| 68.12 | 25.12 | 14.15 |
| 72.89 | 25.88 | 16.37 |
| 76.85 | 26.17 | 18.21 |
| 78.00 | 26.25 | 18.66 |
| 83.10 | 26.21 | 20.63 |
| 85.57 | 26.03 | 21.58 |
| 88.20 | 25.85 | 22.46 |
| 93.30 | 25.19 | 24.17 |