How to compare foil setups
Compare foil setups in Foilbench: the comparison answers the core question — What changes if I swap this part?
Quiver vs. compare
Compare (this page) — overlay up to two curves in panel D.
My quiver — save and load named setups (My quiver).
What changes? — plain-language trade-offs below panel D (Trade-off).
Workflow
- Configure the setup — all parameters as desired
- Remember current setup — button in the compare group (left column)
- Swap a part — typically front wing or fuselage
- Read panel D — current setup solid, saved dashed
Up to two setups can be saved at once.
What to compare?
| Change | Expected effect in panel D |
|---|---|
| Larger front wing | take-off drops, cruise L/D often worse |
| Slimmer front wing (higher AR) | peak L/D rises, narrower stall margin |
| Longer fuselage | trim feel, rear-wing lever, slightly more drag |
| Shorter mast | less mast drag at the same ride height |
Panel E shows where drag changes come from.
Persistence
Saved setups live in browser localStorage (pumpfoil.compare.v1) and survive a reload.
To remove: × next to the saved entry.
Interpretation
Reliable comparisons
Relative metrics (Δ take-off, Δ best glide, curve shape in D) are much more reliable than absolute values. The model has systematic uncertainty in friction calibration.
Do not compare: different rider weights or water conditions without matching those parameters.
What you should see
Save PNGv2 1400, switch to PNGv2 1200:
- Take-off metric rises
- Panel D: dashed curve (1400) lies left of the solid one (1200)
- Panel C: flatter polar (lower AR)
→ Metrics · What changes? · First steps