Glossary of maritime terminology

In maritime terms, the X-band is used for marine radar communication, among other uses. These radars are installed on most large research vessels as well as on a number of offshore installations.

Used for ship traffic control and navigation, the radar produces images  that detect physical objects such as other vessels, structures, oil and gas rigs and platforms and coastlines, as well as reflections from the sea surface - something known as sea clutter.

In shipping terms, x-ray stands for the letter X in the International Radiotelephony Spelling Alphabet, which is most often referred to as the NATO Phonetic Alphabet or simply the Phonetic Alphabet. This is the most commonly used group of code words used to clearly communicate the letters of the Roman alphabet, particularly over the radio and is essential in helping seafarers give and receive messages, orders and instructions clearly and correctly.

In maritime terminology, XTE cross track error is a way for sailors and navigators to tell at a glance what their distance to port (left) or starboard (right) of their intended straight track between two waypoints is.

These waypoints may be departure, arrival or transit points that are set on a chart. Cross track error (XTE) is most commonly caused by drift due to environmental reasons and corrective action should be taken as soon as possible.