# AG25 airfoil (Drela AG series)

> What is the exact shape of the AG25 airfoil?

- Category: Airfoils › Other airfoils
- Kind: Standard part
- Basis: Coordinates from the UIUC Airfoil Coordinates Database; thickness, camber and section by Xem Studio
- Page: https://xemstudio.com/objects/ag25-airfoil/ · JSON: https://xemstudio.com/api/geometry?object=ag25-airfoil · Plain text: https://xemstudio.com/objects/ag25-airfoil/sheet.txt
- License: dimension sheet CC BY 4.0 (Xem Studio); files Xem Studio Design License (free to use and sell from, not to redistribute as files: https://xemstudio.com/license/)
- Use in every chat: add https://xemstudio.com/mcp as a connector (https://xemstudio.com/use-with-ai/)

## Overall (mm)

| length | width | height |
|---|---|---|
| 100.0 | 20.0 | 7.58 |

**Exact dimensions.** True size, with no printing tolerance added.

## Notes

- AG25: Mark Drela (AG series; UIUC file titled 'AG25 Bubble Dancer DLG by Mark Drela'). Maximum thickness 7.58 % of chord at 24.7 % chord; maximum camber 2.40 % of chord at 45.4 % chord.
- Coordinates from the UIUC Airfoil Coordinates Database (M. Selig, UIUC Applied Aerodynamics Group), file ag25.dat, titled 'AG25 Bubble Dancer DLG by Mark Drela'. Thickness and camber are computed by Xem Studio from those points (vertical distance at equal x, linear between points).
- The published trailing edge is open (0.096 % chord thick). As on the NACA pages, the file uses a single sharp trailing-edge point: each surface is shifted linearly from zero at the leading edge to meet at the mid point of the published trailing edge, a change of at most 0.048 % chord, at the trailing edge itself.
- The file is a 100 mm chord section, 20 mm deep: scale it uniformly to your chord, or import the STEP and sweep or loft it into a wing. Thickness scales with chord; the shape is the same at any size.

## Sizes

| parameter | value | source |
|---|---|---|
| Max thickness | 7.58 % chord at 24.7 % chord | computed from the UIUC coordinates |
| Max camber | 2.40 % chord at 45.4 % chord | computed from the UIUC coordinates |
| Published points | 160 (81 upper, 80 lower, shared leading edge) | UIUC coordinates |
| Trailing edge as published | open, 0.096 % chord thick | UIUC coordinates |
| y at x = 1.25 % chord | upper +1.438 / lower -0.876 % chord | linear between the published points (UIUC coordinates) |
| y at x = 2.5 % chord | upper +2.160 / lower -1.183 % chord | linear between the published points (UIUC coordinates) |
| y at x = 5 % chord | upper +3.157 / lower -1.542 % chord | linear between the published points (UIUC coordinates) |
| y at x = 7.5 % chord | upper +3.864 / lower -1.741 % chord | linear between the published points (UIUC coordinates) |
| y at x = 10 % chord | upper +4.402 / lower -1.852 % chord | linear between the published points (UIUC coordinates) |
| y at x = 15 % chord | upper +5.150 / lower -1.921 % chord | linear between the published points (UIUC coordinates) |
| y at x = 20 % chord | upper +5.606 / lower -1.860 % chord | linear between the published points (UIUC coordinates) |
| y at x = 25 % chord | upper +5.861 / lower -1.720 % chord | linear between the published points (UIUC coordinates) |
| y at x = 30 % chord | upper +5.965 / lower -1.530 % chord | linear between the published points (UIUC coordinates) |
| y at x = 40 % chord | upper +5.835 / lower -1.075 % chord | linear between the published points (UIUC coordinates) |
| y at x = 50 % chord | upper +5.369 / lower -0.607 % chord | linear between the published points (UIUC coordinates) |
| y at x = 60 % chord | upper +4.643 / lower -0.194 % chord | linear between the published points (UIUC coordinates) |
| y at x = 70 % chord | upper +3.703 / lower +0.118 % chord | linear between the published points (UIUC coordinates) |
| y at x = 80 % chord | upper +2.593 / lower +0.301 % chord | linear between the published points (UIUC coordinates) |
| y at x = 90 % chord | upper +1.354 / lower +0.284 % chord | linear between the published points (UIUC coordinates) |
| y at x = 95 % chord | upper +0.691 / lower +0.154 % chord | linear between the published points (UIUC coordinates) |
| Coordinates source | UIUC Airfoil Coordinates Database: ag25.dat ('AG25 Bubble Dancer DLG by Mark Drela') | UIUC Applied Aerodynamics Group (M. Selig) |

## Where the files are

- UIUC Applied Aerodynamics Group (M. Selig): [UIUC Airfoil Coordinates Database: ag25.dat ('AG25 Bubble Dancer DLG by Mark Drela')](https://m-selig.ae.illinois.edu/ads/coord/ag25.dat) — web — UIUC Airfoil Coordinates Database, public research data; coordinates are facts, cited and linked, not rehosted
- UIUC Applied Aerodynamics Group (M. Selig): [UIUC Airfoil Coordinates Database (original: Mark Drela (AG series; UIUC file titled 'AG25 Bubble Dancer DLG by Mark Drela'))](https://m-selig.ae.illinois.edu/ads/coord_database.html) — web — UIUC Airfoil Coordinates Database, public research data; coordinates are facts, cited and linked, not rehosted

## Free STEP/STL (1 parts, Xem Studio Design License, Xem Studio)

Index: https://xemstudio.com/files/hardware/ag25-airfoil/index.json · license: https://xemstudio.com/files/hardware/ag25-airfoil/LICENSE.md

- ag25-airfoil-section-100mm-chord: [STEP](https://xemstudio.com/files/hardware/ag25-airfoil/ag25-airfoil-section-100mm-chord.step) · [STL](https://xemstudio.com/files/hardware/ag25-airfoil/ag25-airfoil-section-100mm-chord.stl) — AG25 section, 100 mm chord × 20 mm span, 159 points from the published coordinates, single trailing-edge point (scale to your chord)

## Questions

**How thick is the AG25?**

Maximum thickness 7.58 % of chord at 24.7 % chord: 7.58 mm on a 100 mm chord (computed from the UIUC coordinates).

**How much camber does the AG25 have?**

Maximum camber 2.40 % of chord at 45.4 % chord (computed from the UIUC coordinates).

**How do I use it for my wing?**

Scale the 100 mm section to your chord (e.g. 180 mm chord = 180 % scale), then extrude or loft between root and tip sections. For a tapered wing, scale a root and a tip copy and loft between them.

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