Vrai cours

En navigation, True Course (TC) et True Heading (TH) font référence à la direction de déplacement d'un navire ou d'un avion, mais ce sont des concepts légèrement différents :

  1. Vrai Cours (TC):
    • Le True Course fait référence à la direction de déplacement prévue ou prévue, exprimée en degrés par rapport au Nord géographique (le pôle Nord géographique). C'est la direction dans laquelle le vaisseau ou l'avion est censé se déplacer sur la surface de la Terre.
    • Par exemple, un cap vrai de 90° signifie que le navire se dirige directement vers l'est, en considérant le nord géographique comme référence.
  2. Cap vrai (TH):
    • The True Heading refers to the actual direction in which the vessel or aircraft is facing at any given moment. This is also measured in degrees relative to True North.
    • The True Heading reflects the orientation of the vessel or aircraft, which may differ from the True Course due to factors like wind, currents, or other external influences. Essentially, the True Heading describes the direction the vessel is pointing at, which may not always align with the planned True Course.

Relationship Between True Course and True Heading:

  • True Course (TC) is the planned direction of travel to reach a destination, based on geographic coordinates and navigation charts.
  • True Heading (TH) is the actual direction the vessel or aircraft is facing or following at any moment, which may differ from the True Course due to environmental factors (such as wind or current).

true course img1

Example:

  • If the True Course (TC) is 90°, this means the vessel is supposed to travel due east according to geographic north.
  • However, the True Heading (TH) may be 85° because the vessel could be pushed off course by a wind or current, causing the actual direction it is pointing to differ slightly from the intended course.

In summary, True Course (TC) is the intended or planned direction, while True Heading (TH) is the actual direction the vessel or aircraft is facing.