Drela SuperGee II — a 1.5 m discus-launch glider, drawn to the planvsPiper PA-28 Cherokee — the Hershey-bar wing
root section ag455ct02r → naca652415 · tip section ag47ct02r → — · area 218576 mm² → 14868144 mm² · tip chord 94 mm → 1626 mm · mac 151 mm → 1626 mm · te thickness 0 mm → 3 mm
units
These analyses are not directly comparable
- different trim loads (2 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.
- Drela SuperGee II — a 1.5 m discus-launch glider, drawn to the plan
- Piper PA-28 Cherokee — the Hershey-bar wing
What changed
| Property | Drela SuperGee II | Piper PA-28 Cherokee | Change | % |
|---|---|---|---|---|
| Geometry | ||||
| Span | 1498 mm | 9144 mm | +7646 mm | +510.4% |
| Root chord | 183 mm | 1626 mm | +1443 mm | +788.5% |
| Tip chord | 94 mm | 1626 mm | +1532 mm | +1629.8% |
| Sweep parameter | 3.400 | 0.000 | -3.400 | -100.0% |
| Dihedral | 4.00° | 7.00° | +3.00° | +75.0% |
| TE thickness | 0 mm | 3 mm | +3 mm | +900.0% |
| Sections | 30 | 40 | +10 | +33.3% |
| Tip cap reach | 0.400 | 0.300 | -0.100 | -25.0% |
| Derived | ||||
| Aspect ratio | 10.266 | 5.624 | -4.643 | -45.2% |
| Area | 218576 mm² | 14868144 mm² | +14649568 mm² | +6702.3% |
| Taper | 0.514 | 1.000 | +0.486 | +94.7% |
| MAC | 151 mm | 1626 mm | +1475 mm | +973.4% |
| Sections | ||||
| Root section | ag455ct02r | naca652415 | changed | — |
| Tip section | ag47ct02r | — | changed | — |
| Shapedeviation at matched span fractions, 64 samples | ||||
| Chord deviation (max) | 1532 mm | |||
| Chord deviation (RMS) | 1480 mm | |||
| Twist deviation (max) | 0.00° | |||
| Dihedral deviation (max) | 509 mm | |||
| Tip cap deviation (max) | 4191 mm | |||
Performance
CoefficientsDimensionless — how good the shape is, independent of size and speed.
Spanwise
withheld — “Drela SuperGee II” integrates to CL 0.056 against the polar’s CL at the same α (this analysis predates the loading reporting its own) 0.371 (0.15×); “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
| CD | Drela SuperGee II | Piper PA-28 Cherokee |
|---|---|---|
| 0.014 | 0.259 | 0.382 |
| 0.016 | 0.290 | 0.401 |
| 0.017 | 0.327 | 0.427 |
| 0.018 | 0.347 | 0.443 |
| 0.019 | 0.371 | 0.458 |
| 0.022 | 0.425 | 0.497 |
| 0.025 | 0.473 | 0.537 |
| 0.026 | 0.491 | 0.549 |
| 0.032 | 0.574 | 0.613 |
| 0.037 | 0.631 | 0.666 |
| 0.041 | 0.681 | 0.699 |
| 0.060 | 0.807 | 0.848 |
| 0.062 | 0.819 | 0.860 |