FAA Ground School Practice Test

What does a magnetic compass indicate when a left turn is initiated from a north heading in the northern hemisphere?

1. It will indicate a turn toward north

2. It will indicate a turn toward west

3. It will indicate a turn toward south

4. It will indicate a turn toward east

The correct answer is: It will indicate a turn toward east

When a left turn is initiated from a north heading in the northern hemisphere, the magnetic compass behaves in a unique manner due to the influence of magnetic dip. As the aircraft begins to turn left, the compass will initially lag behind the actual turn, indicating a heading that seems to be toward east. This phenomenon occurs because the magnetic compass is subject to deflection from the turn, and as the plane turns left, the compass registers the east heading before accurately reflecting the new direction. In the northern hemisphere, the magnetic compass tends to show a turn toward east when making a left turn from north due to the magnetic field's interaction with the aircraft's heading change. Understanding this behavior is crucial for pilots, as it underscores the importance of relying on other navigational tools, such as the heading indicator, to maintain accurate awareness of the aircraft's true heading during turns.