How is water depth indicated on a fathometer?

A fathometer, also known as a depth sounder, utilizes sonar technology to measure water depth. The correct way it indicates water depth is through a single digital readout displayed on a video screen. This digital readout provides a precise and easily understandable measurement of the depth beneath the vessel, making it straightforward for the crew to monitor and assess underwater conditions in real-time.

The use of a digital display allows for quick recognition of changes in water depth, which is essential for safe navigation, especially in shallow or potentially hazardous waters. Digital fathometers provide accuracy and often include features like depth range scaling, which can enhance the navigational experience.

While other methods of indication, like graphical waves or analog needles, might display depth information in different formats, they may not offer the clarity or precision that a digital display does. Audible alarms, while useful for alerting the crew when certain depth thresholds are reached, do not directly communicate the current water depth in a numeric form. Hence, the choice of indicating water depth through a single digital readout is the most effective and reliable method.