How can you verify the heading indicator accuracy during flight?

• A. Cross-check with the magnetic compass and use the turn and bank information to detect discrepancies
• B. Rely solely on GPS heading
• C. Use the attitude indicator to verify heading
• D. Compare with the VOR course

Answer: (A)

Heading indicators can drift over time because they are gyroscopic and affected by precession and accelerations. The best way to verify accuracy in flight is to treat the magnetic compass as the reference for your actual heading and to watch the turn information to confirm the rate of heading change matches what you’re doing in the cockpit. When you roll into or out of a turn, the heading shown by the indicator should change in step with the compass heading and at a rate consistent with the indicated turn rate. If the magnetic compass and the heading indicator disagree, or the indicated turn rate doesn’t match the actual turn, the heading indicator is out of calibration or drifting and should be re-synced with the compass.

Relying solely on GPS heading isn’t ideal for this check since GPS-derived heading can be affected by wind, ground track versus heading, or satellite availability. The attitude indicator doesn’t provide heading information, so it can’t verify heading accuracy. Comparing with a VOR course is useful for navigation, but it doesn’t directly test the heading indicator’s accuracy during flight.