Posted on July 30, 2017July 30, 2017 by Dan HortonCool Fishing Airplane Wittman Buttercup, on wheel skis. The owner uses it to fly north and go ice fishing. Our resident aerodynamicist was intrigued by its unusual wingtips. Dan HortonDan Horton says he is "just a homebuilder." He has been a pilot more than 30 years and currently flies a custom RV-8.