Which navigational error occurs during turns towards North or South?

The navigational error that occurs during turns towards North or South is known as the Northerly turning error. This error is primarily associated with magnetic compasses in aviation. When an aircraft turns towards the North or South, the compass may exhibit a lag in indicating the correct heading, resulting in an erroneous reading. This phenomenon occurs because the compass card is influenced by the Earth's magnetic field and its own inertia during the turn.

As the aircraft begins to turn, the compass tends to momentarily swing in the opposite direction of the intended turn. For instance, if an aircraft is turning towards North, the compass may initially indicate a heading that is less than the actual heading, while a turn towards South may lead to a similar lag in showing the true heading. Pilots must be aware of this characteristic behavior of the compass during such turns to adjust their navigation accordingly and maintain accuracy. Understanding Northerly turning error is crucial for pilots navigating in various flight conditions while relying on magnetic compasses for directional guidance.