To start with, a navigator lays out a course on a chart in terms of true north (TN) directions and not magnetic north (MN).
Ukuqala nge, uqhubo lwenqanawa luxhomekeke kwindlela eboniswe ephepheni kwindlela eyinyani yoMntla (TN), izichazi ingesiso isincamatheli esinguMntla (MN).