Which statements about factors that affect vessel movement are true?

• A. Wind
• B. Sea
• C. Current
• D. All of the above

Answer: (D)

Movement of a vessel is shaped by environmental forces acting on it: wind pushes on the hull and superstructure, changing the course and speed; waves from the sea affect the vessel’s speed, stability, and direction through wave interactions; and currents move the water around the vessel, creating set and drift that can push you off your planned track. These factors can combine in any given conditions, so each one impacts how you move through the water. Because wind, sea conditions, and current all influence movement, the statement that all of them are true is the best answer. In practice, mariners evaluate wind direction and strength, wave state and direction, and current strength and direction together to plan heading and speed.