The standby magnetic compass is a backup magnetic heading reference. The standby magnetic compass is below the overhead panel. The standby magnetic compass has a circular heading indicator card. The card floats in a case filled with liquid. The liquid does not permit the card to move quickly. There are two magnets in the standby magnetic compass. The magnets are parallel to each other, and they are in the horizontal plane. The magnets align the compass with the magnetic flux lines of the earth. The standby magnetic compass has N-S (north-south) and E-W (east-west) compensation screw. This screw change the position of the magnets. Use the compensation screw to correct for magnetic deviations generated by electrical currents in the flight deck.
Author – Deniz Turan
