What signal should you hear when a power boat is underway?

When a powerboat is underway, you should hear the sound of its engine running, which indicates it is in motion. Additionally, the boat may use a sound signal, such as a horn or whistle, to communicate its presence to other vessels, especially in crowded or restricted waters. Common signals include one prolonged blast for a powerboat moving away from the dock and short blasts to indicate maneuvers. Always be aware of these sounds for safety on the water.