# Rigid wing sail

> Why do some boats use rigid wing sails?

- Category: Boat design › Sailboat appendages
- Kind: Standard part
- Basis: Design rules and figures from the cited sources; example geometry by Xem Studio
- Page: https://xemstudio.com/objects/wing-sail/ · JSON: https://xemstudio.com/api/geometry?object=wing-sail · Plain text: https://xemstudio.com/objects/wing-sail/sheet.txt
- License: dimension sheet CC BY 4.0 (Xem Studio); files CC BY 4.0 or their publisher's 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

- A wingsail is a rigid or semi-rigid airfoil with independently adjustable segments, like an aircraft wing with flaps. It gives more lift and better lift-to-drag than soft sails (Wikipedia).
- At 30 deg apparent wind a wingsail works at ~10 deg angle of attack vs 15 deg for a jib and 20 deg for a mainsail. Drawbacks: it can't be reefed, must be removed ashore and costs more.
- Used on: C Class Catamaran, USA-17.

## Sizes

| parameter | value or range | source |
|---|---|---|
| AoA at 30 deg apparent wind | wing 10 deg; jib 15 deg; main 20 deg | Wikipedia (Wingsail) |

## Where the files are

- Wikipedia: [Wingsail](https://en.wikipedia.org/wiki/Wingsail) — web — Publisher's page; dimensions are facts

## Questions

**Can it be reefed?**

No, typically fixed area (Wikipedia).

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