Airfoil selection with a documented why-#1

Peak CL is not a selection process

Picking an airfoil from a spreadsheet of peak CL max is how programs revisit the same argument six months later. HENFOIL’s selection path is built for a documented trail.

Build the evidence

You create or import candidates, pass geometry gates, and run VIC polars under the conditions that matter. Envelopes capture cruise efficiency, climb, stall margin and robustness to Re or manufacturing scatter — not a single magic number.

Weighted compare and why-#1

Weighted compare scores candidates against your weights and surfaces a why-#1: which metrics drove the rank. The point is not a black-box score. The point is a sentence you can defend in review.

Batch at serious scale

Batch viscous runs evaluate many sections or conditions. Async jobs keep large sets workable. The same method IDs and gate language apply whether you ran three foils or three hundred.

Export the story

When a polar and geometry are good enough to archive, export a datasheet or design-review PDF — or a HENFOIL_AirfoilDesignPackage with coordinates, metrics, polar / validity and provenance. Selection is still engineering judgement. HENFOIL makes the early decision repeatable and reviewable.

In simple words: what this page is for

Weighted compare, envelopes, ranking and export — so the winning section has a reason you can show in review.

This lesson exists because section decisions fail when geometry, method labels and selection reasons are scattered. Airfoil selection with a documented why-#1 helps you keep a clean trail from shape to polar to choice.

Why the topic matters

Engineers lose time when a title sounds clear but the page only sketches the idea. This article expands Airfoil selection with a documented why-#1 so you can answer three questions without jargon: what is the idea, when do you use it, and how do you check it in a HENDOI product.

Read the sections above for the core definitions. Use the steps below to move from reading into a real project trail you can share with a teammate.

How to apply this in HENDOI

In practice: create a HENDOI account or log in, open HENFOIL, bring a section in (create, import DAT, or digitize), pass the geometry gate, climb the analysis ladder only as far as the decision needs, then compare and archive. Every calculated number should keep its method label.

When the section choice is ready for the aircraft, continue in HENSYNTH for mission, compliance and trades. Same account. Same plans.

What this page will not claim: a teaching polar or geometry note is not a flight-Re certificate. HENFOIL labels methods so you know what you bought. Tunnel data and professional judgement still sit outside any single software run.

Checklist before you leave this page

• Can you state the idea of Airfoil selection with a documented why-#1 in one sentence?
• Do you know which product owns the next action — HENFOIL or HENSYNTH?
• Will every number you keep carry a method label or a stored-run source?
• If you are new here, have you opened Register or Login?

Related reading on this site

• The HENFOIL analysis ladder: when to escalate
• Create airfoil fields: NACA, analytic and CST — what each digit means
• Digitize field-by-field: every control, why fill it, what you get
• Import and digitize airfoils into HENFOIL
• All HENDOI blog articles
• HENFOIL product page
• HENSYNTH product page
• Pricing — Student, Professional & Team
• FAQ
• Login · Register now