Stall and flow control
Leading-Edge Stall vs Trailing-Edge Stall: How Airfoil Geometry Changes Stall Behavior
HENDOI · 27 October 2026
Thickness, nose radius and camber choose the stall pattern. A thicker, blunter nose tends to stall from the trailing edge. A sharper nose tends to stall from the leading edge.
Geometry picks the path
The stall-type lesson names the three classical patterns: trailing-edge stall, leading-edge stall and thin-airfoil stall. This page is how the drawing chooses among them. The pressure peak at the nose and the recovery at the tail are both consequences of thickness, nose radius and camber. Whichever fails first sets the stall you get.
The geometric tendencies
| Geometry | Stall tendency | Why |
|---|---|---|
| Thicker section, large leading-edge radius | Trailing-edge stall | The nose peak stays mild. Separation starts at the rear and walks forward. The lift curve rounds off. |
| Moderate thickness, smaller nose radius | Leading-edge stall | A short bubble near the nose bursts, or the nose separates abruptly. The lift curve peaks and drops. |
| Thin section, or a low-Re section with a fine nose | Thin-airfoil stall | A long bubble grows from the leading edge and covers more of the upper surface as angle rises. |
| More forward camber, or a drooped nose | Often a kinder nose, with a moment and cruise cost | Droop lowers the peak at high angle. It is a stall device as much as a camber device. |
| Aft camber, a plain flap | Higher CLmax, often an earlier geometric stall angle | The rear is loaded. Separation still often starts there, while the lift curve has been shifted up. |
These are tendencies at a given Reynolds number. The same 12% coordinates can move from a bubble stall at Re = 10⁵ toward a trailing-edge or leading-edge break at several million. Roughness at the nose pushes a trailing-edge stall toward a leading-edge break by removing the laminar layer that had been protecting a mild peak. Quote the Re and the surface with the pattern.
What to change if the pattern is wrong for the airplane
- An abrupt nose stall on a light aircraft or a UAV: more leading-edge radius or a small nose droop, then a new polar. Do not only add wing area and keep the cliff.
- A gentle stall that costs too much cruise drag: you may be carrying more nose radius than the cruise Mach number wants. The fix is a new pressure distribution, not a wish that the stall type stay while the peak gets sharper.
- A tip that stalls first: the tip section and the tip Re are the geometry that matters, plus twist. A docile root section does not rescue a fine tip.
Where this sits in the series
In simple words: what this page is for
Thickness, nose radius and camber choose the stall pattern. A thicker, blunter nose tends to stall from the trailing edge. A sharper nose tends to stall from the leading edge.
This lesson exists because section decisions fail when geometry, method labels and selection reasons are scattered. Leading-Edge Stall vs Trailing-Edge Stall: How Airfoil Geometry Changes Stall Behavior 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 Leading-Edge Stall vs Trailing-Edge Stall: How Airfoil Geometry Changes Stall Behavior 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 Leading-Edge Stall vs Trailing-Edge Stall: How Airfoil Geometry Changes Stall Behavior 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
- What Is Airfoil Stall? Comparing Leading-Edge and Trailing-Edge Stall
- How to Calculate the Leading-Edge Radius of an Airfoil from Coordinate Data
- Leading-Edge Radius and Trailing-Edge Geometry: Effects on Airfoil Performance
- How Leading-Edge Slats Delay Airfoil Stall and Increase Maximum Lift
- All HENDOI blog articles
- HENFOIL product page
- HENSYNTH product page
- Pricing — Student, Professional & Team
- FAQ
- Login · Register now
- Previous: Skin-friction drag vs pressure drag
- Next: What is a post-stall airfoil polar?
- 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.
Both products live
Use this lesson in the HENDOI workspace
This page sits in Stall and flow control. HENFOIL and HENSYNTH are both live on one account. These articles are screening lessons — not certification reports.
Live · section
HENFOIL
Turn this lesson into a section you can draw, check, analyse and compare. Run the polar at the Reynolds number of the vehicle. The method name stays on the result.
To Know MoreLive · aircraft
HENSYNTH
After the section is chosen, set geometry and mission requirements, run screening, read compliance, synthesize candidates and download or mail the report.
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