Echo

Phonetic alphabet letter E. In marine terminology, “echo” typically refers to the reflection of sound waves off of a surface or object underwater. This reflected sound wave, or echo, is commonly used in techniques such as echo sounding or sonar to determine the depth of the water or to detect underwater objects like fish or submarines.

Course Change: When a vessel displays the Echo flag, it communicates to nearby vessels that it is changing its course to the right (starboard). This is important for navigational safety, as it informs other vessels of the manoeuvre, allowing them to adjust their own courses if necessary to avoid collisions.

Flag

Code Flag Echo (E)

Nautical or signal flags are used at sea to convey messages over long distances. Only black, blue, red, white and yellow are used because these are the only colours readily distinguished at sea. Many different coding schemes have been used, but the International Code is the most common.