From Airfoil Coordinates to Wing Geometry: A Practical Aerospace CAD Workflow

The workflow, in the order that prevents rework

1. Freeze the sections. One normalized file per station family — often a root, a break and a tip — each already cleaned, hashed and attached to the polars that justified it. Do not loft a section you have not analysed at the Reynolds number of that station.
2. Freeze the planform. Spanwise locations, chord at each location, sweep of the leading edge or of the quarter-chord, and twist. These numbers are the wing. The airfoil file does not contain them.
3. Build one sketch per station by the CAD-sketch rules: scale by local chord, cosine-spaced spline, explicit trailing edge, chord line constrained, leading edge at a named point.
4. Apply twist about the quarter-chord (or about the axis you documented). Positive nose-up has to match the sign you used in the aerodynamic model, or the stall you move to the root with washout will move to the tip in the solid.
5. Loft in spanwise order. Use the same point correspondence on every section so the loft does not twist the upper surface into the lower. A root with 160 points and a tip with 40, joined by nearest index, is a classic way to make a crumpled leading edge.
6. Cut the spar faces and the trailing-edge thickness from the loft and check that the spar depth matches the thickness distribution you required. If the spar does not fit, the section changes and the polars are out of date.
7. Section the solid and overlay the analysis coordinates. Thickness, camber and leading-edge radius should return within the tolerance you set when you resampled. This is the gate between CAD and the polar database.

What this model is, and what it is not

When the overlay in the last step fails, stop and repair the sketch. When it passes, the wing geometry and the airfoil database describe the same object. That is the practical end of the path that started from a coordinate file: a section you can defend, a loft that matches it, and a polar whose Reynolds number belongs to the station where the loft is cut.

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Where this sits in the series

In simple words: what this page is for

A wing CAD model is a loft through several scaled, twisted section sketches. The loft is faithful only if every sketch is the airfoil you analysed, at the chord and twist of that station.

This lesson exists because section decisions fail when geometry, method labels and selection reasons are scattered. From Airfoil Coordinates to Wing Geometry: A Practical Aerospace CAD Workflow 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 From Airfoil Coordinates to Wing Geometry: A Practical Aerospace CAD Workflow 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 From Airfoil Coordinates to Wing Geometry: A Practical Aerospace CAD Workflow 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

• Active Flow Control on Airfoils: Suction, Blowing and Synthetic Jets
• What Is the Aerodynamic Center of an Airfoil? Location, Meaning and Applications
• How to Identify Numerical Convergence Problems in Airfoil Analysis
• How to Build an Airfoil Analysis Database with Consistent Simulation Conditions
• All HENDOI blog articles
• HENFOIL product page
• HENSYNTH product page
• Pricing — Student, Professional & Team
• FAQ
• Login · Register now

• Previous: Estimate wing performance from 2D polars
• Next: How to calculate the NACA mean camber line
• Index: all HENFOIL airfoil lessons

These pages teach the ideas. They are not wind-tunnel data and not a certification analysis. When a number matters, compute it at a stated Reynolds number, Mach number and transition setting, and keep the method label on the result. In HENFOIL that production polar is a VIC polar — see the analysis ladder and the polar field guide.