You have another ship overtaking you close aboard to starboard. You have 3 radar targets bearing 090° relative at ranges of 0.5 mile, 1 mile, and 1.5 miles. In this case, the unwanted echoes are called __________.

In navigating situations with radar, especially when there are multiple radar targets, understanding echo types is essential for proper interpretation of the radar display. When you have simultaneous returns from multiple objects at various ranges, as described in the scenario, these returns can generate what are referred to as multiple echoes.

Multiple echoes occur when radar waves bounce off of several objects and return to the radar receiver, creating several returns on the radar screen. This often presents as several echoes that can clutter the display, making it challenging to discern which are the true targets and which are unwarranted returns from other sources. In this case, the ship is receiving echoes from three radar targets, which are all relatively close and at specific ranges. The situation broadly exemplifies the attributes of multiple echoes, where the returned signals are mixed, creating potential confusion for the navigator.

By correctly identifying multiple echoes, a navigator can take appropriate measures to verify the targets, maintain safety, and ensure effective situational awareness while underway. Understanding the nature of these echoes can also aid in avoiding misjudgment regarding the positions and movements of nearby vessels.