Public charts, trusted data, and sensitive seabeds

Royal Navy survey ships measure sea depth, wave height, barometric pressure, and seabed shape before sending data to the UK Hydrographic Office for navigation publications. Commercial and naval vessels use the same dependable charting system. Government ownership gives customers institutionally independent data while allowing sensitive submarine details to be withheld or reduced on public products. HMS Scott's multibeam sonar can survey about 150 square kilometres of ocean floor per hour, which shows the scale of modern collection. Although it is not an anti-submarine set by design, its seabed picture could expose a submarine attempting to hide on the bottom. The same system therefore has both public and military value.