Course alteration & wheel over positions
Alteration points should be marked off with bearings/ranges of terrestrial targets and/or geographical coordinates. Wheel over positions shall be marked using ships maneuvering data while navigating in confined waters and large scale charts.
Parallel indexing
This is useful method of monitoring cross track tendency in any condition of visibility. It is a particularly valuable tool approaching port and during pilotage when the master is able to continually monitor the vessels position in this way while the OOW plots the position obtained from other data.
