WIG boat with wingsail

Hello! Recently I came across in the web many multihull hydrofoil boats with either conventional sails or wingsails. First I wanted to build a scale model of my own design of such boat, actually to just test the self-orienting wingsail I thought of, but then I came up with the idea instead of a frame to use a triangle wing (like those on Lippisch's ekranoplans like X-113) in corners of which would be 3 thin hulls. On forward side hulls there would be installed 2 wingsails in arrangement as /___\, also those 2 hulls will have foils like on Hydroptère trimaran & aft hull also having one foil+rudder. So it would look like a wind-powered ekranoplan with foils.
I'd like to know whether there are already projects or real models or boats like that, or is what I wrote there actually can be feasible?

Kind regards

 

It would look like this:

 

wig is for flying

WIG make little sense if you intend to keep parts of the boat in the water unless you use "negative" WIG to make sure you do not fly off and stay in the water (like the shrouds in race cars). Luc

 

There were some WIG/ekranoplan projects that had foils to ease the transition or for stability during the flight. Or better to say those are boats with wing to use that WIG effect & take some of the boat's weight from the foils to reduce the cavitation:
http://motorka.org/ekranoplany/1841-katera-s-aerokrylom.html
http://asus2.ru/ekranoplany/89-proekty-hakliza-i-veylanda.html
http://oi49.tinypic.com/11hguvl.jpg
Also, just stumbled on this futuristic yacht - http://www.news.com.au/travel/holiday-ideas/flying-super-yacht-revealed/story-e6frfqf9-1226003656725

 

Does futuristic mean "will never be built"?
It's a very pretty rendering, but there are no real performance estimates and no
indication of how much material is used to carry the unspecified payload.
Another student project that impresses news editors looking to fill space.

 

Ok, so I read that in case of hydrofoil/ekranoplan the speed should be like 150-200 km/h or the wing should be massive for the WIG to take an effect, so a "wind-powered ekranoplan" is a fail idea unless it can be an extra-light craft + filled with helium... xD
However, I think with current arrangement it can be just as a wingsail hydrofoil, while equipped with some propulsion like waterjet or just propeller it might be well as an ekranoplan with hydro-stabilization. Also would be usefull to make wingsails to be able to turn around the horizontal axis on like 90 degrees, increasing the overall wing surface of the craft.

 

I think Bernard Smith beat you to it. By 50 years.

The latest incarnation is SailRocket.

 

That might be close but not much. The boat glides on the water but not flies above it as the Hydroptere trimaran, uses one foil for stability on course.

 

Interesting "Water Resist" projects by Jean Margail - http://foils.wordpress.com/page/7/?archives-list&archives-type=months under the title "o 1999 – Projets « Water resist »"

 

One more interesting concept:

http://jackyamaguchi.wordpress.com/2011/05/05/hyundai-my-baby2-nautica-1/



Model: http://jackyamaguchi.files.wordpress.com/2011/05/yatcht-andre.jpg

I wonder if there's any research behind those pics - looks cool but will it really "fly" with one foil in the water while keep going stable?

 

I have Jane's Surface Skimmers in full sized hard cover for the years 1976-77 and 1987.

There are many interesting variations of historic record which you may wish to visit and are based on similar themes.

 

It's my understanding that stall speeds for WIG tend to be upwards of 30kts. If this is a fair understanding, it seems like a sail-powered WIG might be on the very border of feasibility.

I can see that this idea has been played with before, but has there been much in the way of analysis and tests?

 

I wonder how stable will be such WIG wingsail boat & how much the wind would be affecting the WIG effect. In my design stability will be not only provided by delta-wing itself but by aft rudder/foil (with flaps) too, while the forward side foils would be only needed to ease the transition to fly mode & their vertical parts remain in the water to reduce drag. The boat should be as light as possible too.

 

Ok now for some reality.

I am all about non-conventional configurations and use of airfoils / hydrofoils to avoid misplacement mode drag and the pounding that comes with planing.

At first it would seem that either airfoil above the surface or hydrofoil below the surface could do the job.

When you think of all of the issues with hydrofoils (air entrainment, weed accumulation, underwater AOA/flap control, complex shape fabrication issues, cavitation, damage due to impact) the airfoil above the surface would seem to have lots of potential.

But then there is one item that kills the idea of airfoil above instead of hydrofoil below for a general purpose sailing craft. This issue is fluid speed vs. boat speed. On an upwind run in a fast boat, you have plenty of lift available. Now turn around and try to make headway on a downwind heading. Airfoils have a hard time even generating enough lift to offset their own weight on a downwind run.

 

If it would be able to sail at speed like 2-3 times of wind speed then I think the WIG effect would still be enough to provide some lift.