What does it mean when a vessel sounds two prolonged blasts followed by one short blast?

When a vessel sounds two prolonged blasts followed by one short blast, it signifies that the vessel is signaling a turn to starboard. This specific sound signal is utilized during restricted visibility situations to communicate the vessel's intentions to others.

The use of two prolonged blasts indicates the vessel is reversing, but the addition of a short blast following those prolonged blasts clearly indicates a turn to starboard. This is part of the sound signaling rules established to improve safety and communication among vessels on the water.

Understanding these sound signals is critical for mariners, especially in situations where visibility may be limited, allowing them to understand the intentions of nearby vessels and navigate safely.