Zefyr Wingsail

The Planesail trimaran is 57 feet long and was built in 1990. Planesail weighs 16 tons and has twin 36 HP diesels.

Zefyr trimarans are 43 ft long. Four Zefyrs were built between 1995 and 2000. All 4 Zefyrs are still sailing.

Zefyr 01, Sea Change, owned by Don Tugcu is based in Florida, and has been converted to an Aerorig. For Sale May 2016
Zefyr 02, Ocean Tern, owned by Terry Harper is based in San Diego, California.
Zefyr 03, Angel B, owned by Arth and Susan Loos is based in Baie Curasol, Guadeloupe.
Zefyr 04, Larinka, owned by James Wright is based in Dover, England.

Planesail and Zefyr sailing together.

The Zefyr Wingsail was a development of the Planesail Wingsail.
Both Wingsails are based on the Kellner-Bechereau full span slot to achieve high lift at low wind speeds.
The Walker Wingsails are of composite construction, with doped cloth stretched and shrunk over ribs.
View Zefyr Wingsail drawing as a PDF.

Some aspects of the Zefyr Wingsail design are:

There is snatching and veering when moored.
The original design of the crane type slewing bearing requires regular maintenance.
The slewing bearing is perhaps the weakest element of the wing.
Little provision is made for the Wingsail to be removed and replaced by a crane.
Total Wingsail weight is 688 kg, including the 67 kg slewing bearing.
It is of Nomex / carbon fiber construction.