User:Davandron/wing sail

A wing sail is generally an aerofoil used to propel a vessel. Specifically, the aerofoil is a double-skinned surface, shaped to generate a high lift to drag ratio. Wing sails can be found on sailboats and on ice boats or land yachts.

Due to the wing's high coeffiecent of lift, wing sailed vessels currently hold the world speed records for wind-propelled vehicles.

Contrast with single surface sail

 * Aerodynamics of thin plate to thick section, with reynolds number
 * Lift to drag raises pointing angle
 * Downwind sailing without spinnnacker

- Safer jibs - Self trimming
 * Project specific benefits

Projects, Historical and Current

 * Yellow Pages Endeavour: 1993 project to break the world record. A custom designed asymmetrical trimaran (similar to a proa) that utilized a two section asymmetrical rigid wing XXm by XXm.
 * Macquarie Innovation: The follow-on project to Yellow Pages Endeavour. Uses a similar designed vessel, but a lower aspect ratio rigid wing sail to reduce heeling force.
 * Cognito
 * Atlantis: Designed and built in 2001 by Gabriel Elkaim for a PhD. thesis at Stanford it is based on a 19ft Prindle catamaran and utlizes a low Reynolds number symmeterical rigid wing approximately 1.5m by 5.0m in size, which increases lift via a short flap.
 * "OMER" wing-sail, soft, flexible, variable geometry wing sail,designed and built by Ilan Gonen, based on Elan 37'.