A cathedral hull is a type of boat hull design used on a variety of different-sized boats. looking much like a series of three interlocking v-shaped hulls. Dihedral tunnel boat hull, #us 3996869 a. a hull designed for stable operation as a planing-type hull in rough water conditions. the hull is comprised of a. Home » power boats » power boats 17′ to 20 economical and able 19′ vee-hull outboard boat available with a center all our plans and kits come with full.