Wing-drive

[Kjell Dahlberg]

Wing-Drive is a wind propulsion system. A safety simple sailing system for Catamarans.
http://www.dahlberg-sa.com/kd/index.html

[Morgig]

Looks the same as the Walker Wing sail to me, what’s the differences?

[Kjell Dahlberg]

Common design:
WING DRIVE and Walker WING SAIL are mounted on a central shaft permitting the rig to swing360 deg. A Tail orients the wing /s to the wind. There are no attachments to the hull.
Differences:
WING DRIVE is designed to use on Catamarans with displacement hull.
Walker WING SAIL was designed to be used on a fast running Trimaran.
WING DRIVE is hand operated, controlled by the Crew, in the same way as a steering system.
Walker WING SAIL is Computer controlled. Emergency hand operation is difficult.
WING DRIVE has a self adjusted Spinnaker for easy down wind sailing.
Walker WING SAIL has no Spinnaker.
WING DRIVE has two wings with reduced height of the rig, reducing the capsizing risk.
Walker WING SAIL has one wing. The Computer controls the capsizing risk.
WING DRIVE has a Wedge Tail that holds the rig to an accurate wind angle.
Walker WING SAIL has an Aerofoil Tail that holds the rig to an approximate wind angle.

[SailDesign]

In the "differences" column, I'd take issue with some points:-

While the Walker Wing Sail was developed for a trimaran (Planesail), it has been used successfully (key word) on catamarans, tris, foil-assisted monos, and - gasp! - at least one ship (big, heavy, cargo-carrying thing)
Emergency hand control is easy to use - but a real witch-with-a-"B" to set up
Spinnaker? Easy enough to set one up for a Walker, but the wings are more efficient.
Most Walker wings were multiple element, it all depended on the use. The ship-board unit had 3 wings, IIRC.
The Walker trim-tab system was just as effective as a "wedge" tail, probably more so. Please try to tell the difference between reality and a sales pitch.

Steve

[Kjell Dahlberg]

The Walker Wingsail system was a great idea. But it didn’t work the way John Walker expected. He make tree different wing sail system. One wing,Zephyre 43.Twin wing Blue Nova and triple wings for M.V. Ashington. None of them are in production for the moment. I have been in factory in Plymouth and I have been sailing with the Zephyre 43. It was a fantastic experience. I like the modern wind propulsion. Referent to the differences between the “wedge-tail and a foil tail quit big. Only testing the two tails side to side is possible to appreciate the great difference how they control the angle of attack.

[Andy P]

The land yacht pic is a fake!

the centre pic is a bit of a joke

the proa pic is an 'artists impression ' !

[SailDesign]

Still the best use for a Wingsail, in my opinion.
But then I am a liiiitle bit biased.

[Kjell Dahlberg]

Steve.
I am agreeing with you to use the wind propulsion system on fishing boats. I think you will see a very big change in the fuel bill. The problem with Walker Wingsail System is that it is too heavy, too complicated and too expensive. The WING-DRIVE is light, easier to use and not so expensive.

[ErikG]

Careful now Kjell that ain't no fishingboat!

[Kjell Dahlberg]

Sorry on Trawler Yachts and Fishing boats

[SailDesign]

Be fair, Erik - the hull was based on a fishing boat (see Dim's "Old School" series)

[Skippy]

Wow, how well does this thing work? Looks like the wedge winds up pointing farther up into the wind than the wings, so their backwash is hitting it side-on. Sounds like a lotta windage.

[Kjell Dahlberg]

Skippy,
The Wing.Drive is the easy and safest way of using the wind as propulsion. No physical effort involved. No ropes, no winches no hard work on deck. The wedge tail looks after the set wing angle and with the wedge tail set to “Zero thrust” the Wing-Drive actuate as a wind vane. I have been sailing with my prototype for 2 years with very good result.
Kjell

[kjell]

New Project with twin Wing-Drive on motorsailer. The Wing-Drive originally designed for Catamarans is now projecting to bee installed on a monohull.

[masrapido]

Kjel,

I do not see how you pull the wings down. What if a sailor gets caught in a wing to strong to control and needs to reduce the sails? Is that possible with your wing? I like the wing idea but, for cruising purposes, the only viable wing sails are done by this guy: www.wingsails.com