United States Coast Guard Captains License Practice Exam

What does an alternating red and yellow light on a vessel indicate?

1. In distress and need of assistance

2. Fishing with lines extending out over 150 meters

3. Engaged in public safety activities

4. Restricted in its ability to maneuver

The correct answer is: Engaged in public safety activities

An alternating red and yellow light on a vessel signifies that the vessel is engaged in public safety activities. This type of light is used to alert other vessels and mariners that the vessel is performing functions related to safety and may be operating under specific regulations or protocols that require caution from others in the area. For instance, vessels displaying this light may be involved in search and rescue operations, law enforcement activities, or emergency response tasks, where their presence is crucial for public safety. Recognizing such a light allows navigators to understand the situation and take appropriate actions, such as maintaining safe distances or providing assistance if necessary. Understanding the specific meaning of light signals on vessels is essential for safe navigation, as it helps prevent accidents and ensures that all maritime activities are conducted responsibly. Thus, knowledge of these signals contributes significantly to overall maritime awareness and safety.