What is recommended when altering course to avoid a vessel forward of the beam?

When altering course to avoid a vessel that is forward of the beam, it is crucial to consider the situation carefully to prevent a collision. The recommendation to only alter course if the vessel is being overtaken underscores the importance of maintaining safe navigation and the responsibilities of both vessels involved.

In maritime navigation, when a vessel is approaching from ahead or forward of the beam, both vessels must understand their relative positions and intentions. The vessel that is overtaking has the right to keep its course and speed, while the vessel being overtaken should take appropriate measures to avoid collision. To alter course only if the vessel is being overtaken ensures the vessel maintains a safe maneuvering response based on the navigation rules and situational awareness.

In situations where the vessel is not being overtaken, altering course without clear reason (as suggested in other choices) could lead to confusion or misinterpretation of intentions, increasing the risk of a collision. This approach adheres to the COLREGs, which emphasize maintaining a clear understanding of each vessel's path and actions to enhance safety at sea.