There have been considerable advances in technology in recent years which has meant that a major revision has been necessary. in the past much of the work of the navigator involved the correct use of the controls in setting up the display data- in particular, radar plotting to determine risk of collision. These problems have been largely solved by the development or digital techniques which have allowed the data to be electronically processed resulting, among other facillities, in auto-clutter supression and target tracking (ARPA).
