# Spoiler

> What do spoilers do on a wing?

- Category: Aircraft design › Control surfaces
- Kind: Standard part
- Basis: Design rules and figures from the cited sources; example geometry by Xem Studio
- Page: https://xemstudio.com/objects/spoiler/ · JSON: https://xemstudio.com/api/geometry?object=spoiler · Plain text: https://xemstudio.com/objects/spoiler/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/)

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

## Notes

- Spoilers deploy from the upper surface to spoil the flow, cutting lift and adding drag; they give roll control with no adverse yaw, descent without speed gain, and better braking after landing (FAA PHAK ch.6).
- Gliders use them to control descent rate (FAA). Drela's 3 m Bubble Dancer RC sailplane uses 'a very big 2 x 36 in spoiler' for landing (CRRC).
- Used on: Bubble Dancer (RC sailplane).
- The file is a reference example built by Xem Studio from the numbers above. Sizes the sources do not fix are illustrative; scale the example to your own vehicle.

## Sizes

| parameter | value or range | source |
|---|---|---|
| Bubble Dancer spoiler | 2 in x 36 in on a 120 in span | CRRC |
| Reference build | 300 x 30 mm panel, 60 deg | illustrative |

## Where the files are

- FAA: [Pilot's Handbook of Aeronautical Knowledge (FAA-H-8083-25), Ch. 6 Flight Controls](https://www.faa.gov/sites/faa.gov/files/08_phak_ch6.pdf) — web — Publisher's page; dimensions are facts
- Charles River Radio Controllers (M. Drela designs): [Bubble Dancer 3m RES sailplane](https://charlesriverrc.org/articles/on-line-plans/mark-drela-designs/bubble-dancer/) — web — Publisher's page; dimensions are facts

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

Index: https://xemstudio.com/files/hardware/spoiler/index.json · license: https://xemstudio.com/files/hardware/spoiler/LICENSE.md

- spoiler-wing-segment: [STEP](https://xemstudio.com/files/hardware/spoiler/spoiler-wing-segment.step) · [STL](https://xemstudio.com/files/hardware/spoiler/spoiler-wing-segment.stl) — Wing segment with an upper-surface spoiler panel raised 35° (illustrative)

## Questions

**Spoilers vs flaps on a glider?**

Spoilers dump lift and add drag without speeding up, which suits glider landings (FAA PHAK ch.6).

## Fits with

- [Aileron](https://xemstudio.com/objects/aileron/)
- [Frise aileron](https://xemstudio.com/objects/frise-aileron/)
- [Differential ailerons](https://xemstudio.com/objects/differential-ailerons/)
- [Elevon](https://xemstudio.com/objects/elevon/)
- [Flaperon](https://xemstudio.com/objects/flaperon/)
- [Trim tab and antiservo tab](https://xemstudio.com/objects/trim-tab/)