The latest innovation in rudder technology comes from a study of whale fins. The pectoral fins of some types of large whales have large growths, tubercules, protruding from their leading edge. Research determined that these fins are used for high maneuvering.
Tubercules combine with the fin to produce a range of foil profiles. The effect is to significantly reduce stall resistance (as much as 40%). This makes the foil more efficient and allows it to operate at much more aggressive angles.
Naturally, DMR is looking for any effective way to increase rudder performance. DMR already incorporates changing foil profiles in our D-shape, achieving extremely effective maneuverability, but we believe tubercules can improve their efficiency a bit further without incurring significant cost. Take a look for yourself: