2026 US Sailing Basic Keelboat Complete Practice Test

On a moving boat, the wind you feel is the apparent wind. It’s the wind you experience on deck, created by the combination (vector sum) of the true wind—the actual wind blowing over the water—and the wind generated by your boat’s own motion through the water. This means your speed and direction change what the sails see: as you move faster, the apparent wind shifts toward the bow and often increases in strength, affecting how you trim the sails and steer. True wind, by contrast, is how strong and from which direction the wind would be if you were stationary on the water. Stagnant wind isn’t a real condition you’d experience afloat, and the term relative wind isn’t the standard sailing term for what sails respond to in keelboat practice.