Figure 4.1-2 Latitude Longitude Coordinates

Figure 4.1-2 Latitude Longitude Coordinates

Direction is an angular distance from a reference. Direction, stated in whole numbers, is

measured from 0 to a maximum of 359. The reference for the angle can be either True

North or Magnetic North. True North is the top of the earth whereas Magnetic North is the

point from which all of the Earth's magnetic lines of force emanate. Magnetic North is

currently located near Hudson Bay in Canada. A magnetic compass system converts the

energy from these lines of force to a cockpit indicator reading. Typical military aircraft have

two compass systems: a primary and a secondary/back-up.

The aircrew's primary instrument for determining direction in the cockpit is the Remote

Gyro Vertical Compass Card. This compass uses a remotely located detection element

(called a flux detector) to sense the magnetic field at a point where interference is at a

minimum (such as a wing tip). This sensor converts magnetic energy to an electrical

voltage, which then drives electrical motors that turn the compass card to reflect changes

in aircraft heading (see Figure 4.1-3).

The aircrew's primary instrument for determining direction in the cockpit is the Remote

Gyro Vertical Compass Card. This compass uses a remotely located detection element

(called a flux detector) to sense the magnetic field at a point where interference is at a

minimum (such as a wing tip). This sensor converts magnetic energy to an electrical

voltage, which then drives electrical motors that turn the compass card to reflect changes

in aircraft heading (see Figure 4.1-3).

The aircrew's primary instrument for determining direction in the cockpit is the Remote

Gyro Vertical Compass Card. This compass uses a remotely located detection element

(called a flux detector) to sense the magnetic field at a point where interference is at a

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