Magnetic Compass Flashcards
How does the magnetic compass work?
Magnetized needles fastened to a float assembly, around which is mounted a compass card, align themselves parallel to the earth’s lines of magnetic force. The float assembly is housed in a bowl filled with acid-free white kerosene.
What are the various compass errors?
a) Oscillation error - erratic movement of the compass card caused by turbulence or rough control technique
b) Deviation error - Due to electrical and magnetic disturbances in the aircraft
c) Variation error - Angular difference between true and magnetic north; reference of the isogonic lines of variation.
What are the magnetic compass dip errors?
Acceleration error - On east or west headings, while accelerating, the magnetic compass shows a turn to the north and when decelerating, it shows a turn to the south.
Remember ANDS: Accelerate North Decelerate South
Northerly turing error - The compass leads in the south half of a turn. Lags half of a turn in the north.
Remember UNOS: Undershoot North Overshoot South
