WAYPOINT NAVIGATION AND SYMBOLOGY
The Global positioning system Inertial Navigation Assembly (GINA) is a navigation-grade strapdown
inertial system with an embedded GPS receiver. The GINA ring laser gyro and inertial-grade
accelerometers determine aircraft movement to provide attitude, velocity, and heading. Inertial
Navigation System (INS) position data is refined by the GPS. Waypoint data can be entered on the
DATA displays, and navigation information is displayed on the HSI and the HUD.
COURSE DEVIATION SITUATION STEERING ARROW
The course deviation situation steering arrow (Figure 5) is displayed on the HUD when the selected
steering is TACAN, waypoint (WYPT) or waypoint offset (WO/S) and course (CRS) is selected. The
HSI display mode, CDI or PLAN doesn't affect the HUD steering arrow display format. The orienta-
tion of the situation arrow indicates the difference between the aircraft ground track and the course
line setting. The two dots represent the same deflection scale as the HSI CDI display. The refer-
ence dots are removed when the deviation from the selected course is within one degree with
TACAN selected, 0.4 nautical miles with waypoint or waypoint offset selected and the landing gear
up, or 0.003 nautical miles with waypoint or waypoint offset selected and the landing gear down.
Situation Steering Arrow
Figure 5: WAYPOINT STEERING
GROUND TRACK MARKER
The ground track marker (Figure 5) displays the actual aircraft magnetic track over the ground. A
technique for using the ground track marker to maintain a selected course is to fly a heading that
places the ground track marker directly over the courseline.