When overtaking another power-driven vessel in a narrow channel, what should your first whistle signal be if you wish to pass on your starboard side?

When overtaking another power-driven vessel in a narrow channel, signaling your intention is crucial for safe navigation. If you wish to pass the other vessel on your starboard side, you should sound two short blasts of your whistle. This signal indicates to the vessel being overtaken that you are maneuvering to pass to their starboard side, allowing them to understand your intentions clearly and take any necessary actions to facilitate a safe passing.

The use of two short blasts is part of the sound signal protocol established in the navigation rules, ensuring that vessels communicate effectively, especially in confined waters where maneuverability may be limited and visibility is often reduced. This practice promotes safety and the smooth flow of marine traffic.