CHAPTER 2 TRUE AND APPARENT WIND


When it comes to knowing about the wind the most common source of information is a weather station. Meteorological weather stations are always stationary, which allows them to record accurate readings of the true wind direction and velocity. But, what would happen if the weather station were attached to a moving object, such as a boat or a car? The motion of the weather station would change the wind readings, depending on the direction and speed the weather station is moving. The altered wind direction and velocity, which is different from the true wind direction because of the motion of the weather station, is known as apparent wind.


Since boats are moving objects they always sail in apparent wind. Trim your sails or adjust your course by using the telltales on the sails. Changes in a boat’s course or speed as well as puffs, lulls, lifts and headers will all affect a boat’s apparent wind and require sail trim adjustments or course adjustments. Keep the windward and leeward telltales streaming to maximize your sail trim.


True Wind


Boat’s Forward Motion


10


Table of Contents


Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36  |  Page 37  |  Page 38  |  Page 39  |  Page 40  |  Page 41  |  Page 42  |  Page 43  |  Page 44  |  Page 45  |  Page 46  |  Page 47  |  Page 48  |  Page 49  |  Page 50  |  Page 51  |  Page 52  |  Page 53  |  Page 54  |  Page 55  |  Page 56  |  Page 57  |  Page 58  |  Page 59  |  Page 60  |  Page 61  |  Page 62  |  Page 63  |  Page 64  |  Page 65