Question 327General Subjects - Assistant Engineer

The correct answer is D) Cycloidal propeller. A cycloidal propeller consists of a flat disc set flush with the underside of the vessel's hull, with a number of vertical, rudder-like blades projecting from it. This design allows the propeller to provide both thrust and steering, making it a unique type of propulsion system. The other options are incorrect because: A) Contra-rotating propellers use two sets of propeller blades rotating in opposite directions. B) Tandem propellers use two separate propellers aligned one after the other. C) Helicoidal propellers have blades arranged in a spiral or helix pattern.