🔍 Key Concepts

• Compare where the rudder stock (axis of rotation) is located relative to the total rudder area in the illustration. • Review the definitions of balanced, unbalanced, and semi-balanced rudders in terms of how much area lies forward of the stock. • Notice whether there is any separate flap or extra hinged surface that would suggest a special type (e.g., contra‑guided or flap) rudder.

💭 Think About

• On the sketch, does any significant portion of the rudder’s surface extend ahead of the turning axis, or is all of the area aft of that axis? • If some area is forward of the stock but the rudder is still partly supported by the sternpost/skeg, which standard rudder type matches that combination? • Do you see any secondary movable section on the trailing edge that would justify calling this a contra‑guided or special flap-type rudder? If not, which of the more basic three types is most reasonable?

✅ Before You Answer

• Identify the exact position of the stock (label A) and mentally divide the rudder area into forward vs. aft of that point. • Confirm whether any portion of the rudder edge projects ahead of the sternpost/skeg (label C) or whether it is all behind it. • Before choosing, rule out options that require features not actually drawn (such as a distinct flap or multiple moving parts).