# Soft sail (Bermuda rig)

> How does a soft sail compare with a wing sail?

- 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/soft-sail-bermuda/ · JSON: https://xemstudio.com/api/geometry?object=soft-sail-bermuda · Plain text: https://xemstudio.com/objects/soft-sail-bermuda/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

- Soft sails take camber from the wind and can be reefed; they need more angle of attack than a wing (Wikipedia).
- The IOM class uses a Bermuda sloop with fractional rig and three sizes (onemetre.net).
- Used on: International One Metre (IOM).

## Sizes

| parameter | value or range | source |
|---|---|---|
| IOM A rig area | ~6000 sq cm | onemetre.net |
| IOM B / C rig | ~4100 / ~2700 sq cm | onemetre.net |
| IOM A rig aspect ratio | ~4.8 | onemetre.net |

## Where the files are

- Wikipedia: [Wingsail](https://en.wikipedia.org/wiki/Wingsail) — web — Publisher's page; dimensions are facts
- onemetre.net: [The IOM class](https://onemetre.net/OtherTopics/IOMclass/IOM.htm) — web — Publisher's page; dimensions are facts

## Questions

**How many rigs does an IOM have?**

Three sizes: A (~6000 sq cm), B (~4100) and C (~2700) (onemetre.net).

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