Almost all planing powerboat hulls are of single chine configuration and most have 'chine flats' or 'planing chines' and occasionally 'planing strakes' that assist with getting onto, and maintaining the planing attitude. It is my opinion that chine flats are desirable on all planing craft. Intermediate planing strakes may not be worthwhile on boats intended to perform at less than 30 knots. Planing chines or flats, will start with a small or no flat, at, or near the bow and the width of the flat will gradually increase, until it reaches its widest point somewhere just aft of amidships and maintains this width through to the stern. The efficiency of the 'chine flat,' may be improved by canting it downward by say 2 to 4 degrees throughout its length.
HEAVY DISPLACEMENT | MEDIUM DISPLACEMENT | SEMI-DISPLACEMENT or SEMI-PLANING HULLS | PLANING HULLS
PLANING FLATS AND STRAKES | ROUND BILGE | RADIUS CHINE BUILDING TECHNIQUES | POWER CATAMARANS