What sound signal indicates a vessel is changing its course to starboard?

The correct indication that a vessel is changing course to starboard is represented by two short blasts. According to the International and Inland Navigation Rules, sound signals are used to communicate a vessel's intentions to other vessels, particularly in situations where visual signals may not be clear.

When a vessel sounds two short blasts, it conveys that the vessel intends to turn to starboard. This is especially important in navigation to prevent collisions, as it alerts nearby vessels about the maneuver. The usage of specific signals for different actions helps to standardize communication on the water, ensuring that all mariners understand what a vessel is planning to do.

The other sound signals serve different purposes; for example, one prolonged blast indicates that a vessel is leaving a dock or a slip, three short blasts indicate that a vessel is operating astern propulsion, and one short blast signifies an intention to turn to port. Each blast pattern has its unique context, promoting safe navigation and mutual awareness among vessels.