All versions of Hullform can automatically generate a tapered foil section, following the
NACA "00xx" shape. This means you can tack a faired keel onto your design using
only a few keystrokes. All you need to provide is the line where the foil starts,
the start and end coordinates of the base and tip of the foil, its span and (of
course) the NACA foil code.
The professional versions have the added advantage of readily handling the short lines which run through the foil, and the rounded nose at the foil's leading edge.
At right is a wireframe view of an extreme case, highlighting the features supported by the professional versions of Hullform. The foil has been made fatter than normal (NACA 0025) so that you see its form more clearly. Notice that the program has inserted extra sections where needed, to ensure sufficient detail is possible where it is needed.