On a turn from a northerly heading, how will the compass behave?

When an aircraft turns from a northerly heading, the behavior of the compass is influenced by the Earth's magnetic field and the principles of magnetic compass operation. The correct answer indicates that the compass will lag behind the airplane during the turn. This lag is due to the inertia of the compass fluid and the magnet's inability to respond instantly to changes in direction.

In a turn from north, the compass initially continues to point towards the magnetic north pole, which can create an apparent lag in the reading compared to the heading the aircraft is actually flying. As the aircraft continues the turn, the compass eventually realigns itself with the new heading, but this realignment does not happen instantaneously. Pilots must be aware of this lag to maintain accurate situational awareness and correct their heading as necessary.

In summary, during a turn from a northerly heading, the compass experiences a delay in its response, displaying a heading that is behind the aircraft's actual heading until it stabilizes. This is essential for pilots to account for when navigating using a magnetic compass.