One must test the new rudder before sailing. this flap rudder is just one of the unique rudder designs. Also known as the Becker rudder. a flap rudder is a specific type of multi-section rudder used on boat and ships. The flap rudder is designed to improve the effective lift generated by the rudder and hence improve the manoeuvrability of the ship. Credit @shipspotter_hayriyay | Oceanic Insight