What is the difference between the NOAA ENC® and the National Imagery and Mapping Agency Digital Nautical Chart (NIMA DNC™)?
Answer – The NOAA ENC® is based on the International Hydrographic Organization Transfer Standard for Digital Hydrographic Data, Publication S-57 and is approved by the International Maritime Organization for SOLAS class vessels to use for navigation in an Electronic Chart Display and Information System. The DNC™ uses the Vector Product Format, which is a NATO standard for digital military map and chart data. They are both vector format charts and are based on NOAA nautical charts, just in different formats. The NOAA ENC®, however, has certain critical features such as aids to navigation and channel limits created from larger scale, more accurate information than can be obtained by digitizing a paper or raster nautical chart.
