Published online by Cambridge University Press: 18 January 2010
There are two stages in the determination of position from current observations. The observations are first resolved into positional form on the chart and plotted so as to give either a fix or a position line. When more than two position lines are available, some of the information is redundant and a problem exists of determining the most likely fix. In the case of air navigation, the number of position lines seldom exceeds three, and the determination of position in this case has been studied in a previous article.