What are the effects of turning errors in the magnetic compass?

When navigating with a magnetic compass, turning errors can result in oscillation and inaccuracies during turns. This phenomenon occurs due to the compass's tendency to lag in response to changes in heading. As a vessel or aircraft initiates a turn, the compass may not immediately align with the new heading, leading to a temporary error in the indicated direction. This can cause the compass to swing back and forth—a condition known as oscillation—making it difficult to ascertain the true heading.

During a turn, the inertial forces acting on the compass card can also affect its accuracy, especially if the turn is made too sharply or too quickly. The result is that the pilot or navigator may not get a reliable indication of the direction they are heading, resulting in potential navigational errors during critical maneuvers. This understanding is crucial for ensuring safe navigation and making timely corrections when using a magnetic compass in dynamic situations.