Magnetic Compass

This document has been prepared in order to present all pertinent information regarding the practical procedures of magnetic compass adjustment in one text. As such, it treats of the basic principles of compass deviations and their correction, and not of ... [Download and Read document]

1     The magnetic compass. The principle of the present day magnetic compass is in no way different from that of the compass used by the ancients. It consists of a magnetized needle, or array of needles, pivoted so that ... [Download and Read document]

Magnetic adjustment. The magnetic compass, when used on a steel ship, must be so corrected for the ship's magnetic conditions that its operation approximates that of a nonmagnetic ship. Ship's magnetic conditions create deviations of the magnetic compass as well ... [Download and Read document]

NOTE: If the adjuster is not familiar with the theory of magnetic effects, the methods of analyzing deviation curves, and the methods of placing a ship on any desired heading, it is recommended to review Chapters II, V and VII, ... [Download and Read document]

Since A is the coefficient of constant deviation, its approximate value is obtained from the above data by estimating the mean of the algebraic sum of all the deviations. Throughout these computations the sign of east deviation is considered plus, ... [Download and Read document]

Until now the principles of compass adjustment have been considered from a qualitative point of view. In general, this is quite sufficient since the correctors need merely be moved until the desired amount of correction is obtained. However, it is ... [Download and Read document]

1     Ship's heading. Ship's heading is the angle, expressed in degrees clockwise from north, of the ship's fore-and-aft line with respect to the true meridian or the magnetic meridian. When this angle is referred to the true meridian, it ... [Download and Read document]

1     Azimuths of the sun. Since accurate compass bearings of the sun can readily be observed for comparison with the sun's calculated true bearing or azimuth (for time, date, and place of the observer) to obtain the compass error, ... [Download and Read document]