Yourbestsailvidéo
Relationships between heading vectors
10 septembre 2023 · 19 min · 2K vues
Ce que couvre cette vidéo
Navigating effectively requires distinguishing between true heading, surface heading, and course over ground (COG). True heading represents the direction of the boat's bow relative to true north, while surface heading accounts for leeway—the lateral drift caused by wind acting on the hull and sails. Leeway is particularly significant for sailboats sailing close-hauled, where the keel's angle of incidence to the water flow creates substantial lateral force. COG and speed over ground (SOG) represent the vessel's actual track and speed relative to the seabed, determined by the vector sum of the surface heading and the current.
To calculate the required compass heading to reach a destination, sailors must plot the desired COG on a chart, account for current velocity and direction, and adjust for leeway. Modern GPS plotters automate these calculations by comparing data from the electronic compass and the paddlewheel log to estimate current. However, these instruments often omit leeway from their internal calculations. Understanding these vector relationships remains essential for verifying plotter data and maintaining an accurate dead reckoning position.
Plus de vidéos de Yourbestsail
De Yourbestsail — voir le bateau, l'équipage et chaque vidéo analysée de la chaîne.
The Sailing Directory Newsletter
Un e-mail avec les meilleures trouvailles de la flotte — les moments, les bateaux et les histoires qui valent la peine d'être regardés. Entrez votre adresse pour recevoir votre propre exemplaire.