The sketch is exacerrated at the stern to show the make up but truly all panels are flat in the real life application with the exception of being bend in one plane.

If you bend two non parrellel panels in their own planes and have them intersect with eachother then the resulting intersection line (the chine) will be curved in two planes. Because this line HAS to lay in both planes ! But each plane itself is still only bend in one plane and therefor not stressed into to compound curve (? right word for it ?)

Do this mind experiement.

Use a flat plat to make yourself a cone. Cut the of at a right angle so the cone is like a round pyramid shape. Now intersect the cone s little below the top with a flat surface. You end up with a circle as a crossectional shape. Now bend this top plate and again make its intersection with the cone. Now the crosssection will be an round but irregular shape. It will not be an ellips although it will appear to be one. No just rotate the top plate. The crossection and chine will be curved and angles in more then one direction but the shape and chine are still the result of only two flat panels bend in only one plane.

My point ? It is extremely hard to tell from chines or crossectional shape whether a shape is made out of the intersection of flat plates bend in only one direction or by stressed plates bend in more then one direction.

Wouter