Does anyone know anything about Tunnel Hulls (like the Laser Vortex)? I am trying to find some hard information Plans, analysis, ?) on the Tunnel Hull Moths of the 1970's.

I have read all sorts of interesting theories but I am beginning to suspect they work just like a catamaran except downwind when it is blowing. Downwind in good wind, the stern sinks to bring the bow up and the area between the hulls at the stern becomes a lifting surface.

Any help is appreciated

I own an M-20 scow sailboat. This is a Melges tunnel hull scow. The tunnel is only in the center of the boat as the bow and stern are typical scow sections. The boat is sailed flat unlike most scows which are sailed on their side. It is very fast off the wind when the bow picks up and it gets on plane. The wake looks like a powerboat. The ltest wersion of the M-20 nis an I-20 which uses a spirit pole and genniker for even high speeds on a reach. The web sites are http://www.inland20.org/ and http://www.m20scow.com/.

Lance