What is the definition of a DP mode where a vessel maintains position relative to a moving surface installation?

The definition of the DP mode where a vessel maintains position relative to a moving surface installation is accurately identified as Follow Target/Follow Sub. In this mode, the Dynamic Positioning system adjusts the vessel's position to keep it aligned with the specified moving reference, such as a floating production unit or an offshore platform that is not stationary.

This mode is particularly useful in scenarios where the vessel is engaged in operations that require precise positioning in relation to a dynamic target, accommodating the movement of that target due to environmental factors such as currents, winds, or operational procedures. By utilizing this mode, the vessel’s DP system continuously computes and applies the necessary corrections to ensure that the vessel stays on course with the target, effectively allowing for simultaneous operations without compromising safety or stability.

Understanding this mode is particularly important for operators and crew members who must be adept at navigating the complexities of working around moving installations. The other choices refer to different functionalities or methods of maintaining position within the DP operational framework, but they do not specifically address the scenario of adjusting to a moving reference point as effectively as Follow Target/Follow Sub does.