Area bearing
Under Flächenpeilung is the generation of a solid image or a digital terrain model from the body of water. Different methods / tools are used depending on the existing water depth and the extent of the measurement area. With a fan echo sounder or several single transducers arranged in a line, extensive depth information is determined and given a time stamp in a PC.
In addition to these depth data, the coordinates (today mostly with GNSS) of the measuring ship and its direction of travel (also with GNSS or with a gyro compass ) must be determined. A motion sensor helps to check the plausibility of the data from the individual sensors. In addition, the properties of the water (conductivity / salinity and temperature) must be recorded. Because these influence the runtime of the signals. A runtime error has a particularly strong effect on a fan-shaped plumb line (the outer beams cover the longest distance). When using single transducers, this is not quite as critical, as all signals follow a perpendicular course in the water. In the on-board IT system, the data of the individual components are linked via the time stamp and saved as raw data for further processing (map, profile or digital model).