In the Northern Hemisphere, what will a magnetic compass indicate when a left turn is entered from a North heading?

When a left turn is made from a North heading in the Northern Hemisphere, the magnetic compass initially indicates a turn toward the East due to the nature of the magnetic compass's operation. In this scenario, as the aircraft begins its left turn, the compass experiences a phenomenon known as "turning error."

This error occurs because the magnetic compass is influenced by the Earth's magnetic field and the aircraft's movements. As the aircraft turns left from North, the compass tends to lag, continuing to show North momentarily even though the actual heading is changing. Gradually, as the turn progresses, the compass will indicate a turn toward the East before settling on the new heading once the aircraft completes the turn.

This behavior reflects the way magnetic compasses are designed, where they naturally precess in a particular manner based upon the Earth's magnetic field and the direction of the aircraft's movement, especially during dynamic maneuvers like turns. Understanding this aspect of compass operation is crucial for effective navigation and is an important concept for pilots to grasp when interpreting compass indications during flight.