Compass must be calibrated for deviation of more than how many degrees?

Compass must be calibrated for deviation of more than how many degrees?

• A. 5
• B. 15
• C. 10
• D. 20

Answer: (C)

Compass deviation is the error in a magnetic compass caused by the aircraft’s metal and electrical systems. To keep the heading indication reliable, this deviation is mapped and corrected through calibration, creating a deviation card that shows how far off the reading is at different headings. The threshold for needing calibration is ten degrees. When the measured deviation exceeds ten degrees, calibration is required to bring the error within an acceptable range. Ten degrees is used as a practical limit because it keeps heading indications accurate enough for safe navigation; smaller deviations would be too conservative to require calibration every time, while larger deviations would leave pilots with substantial misheading unless corrected. So, the correct required deviation for calibration is ten degrees.

Compass deviation is the error in a magnetic compass caused by the aircraft’s metal and electrical systems. To keep the heading indication reliable, this deviation is mapped and corrected through calibration, creating a deviation card that shows how far off the reading is at different headings.

The threshold for needing calibration is ten degrees. When the measured deviation exceeds ten degrees, calibration is required to bring the error within an acceptable range. Ten degrees is used as a practical limit because it keeps heading indications accurate enough for safe navigation; smaller deviations would be too conservative to require calibration every time, while larger deviations would leave pilots with substantial misheading unless corrected.

So, the correct required deviation for calibration is ten degrees.