Garmin GNC 300 - Manual (Page 90)

When the aircraft is within 30 nautical miles of the destination airport, the GNC
300 will automatically arm the approach, and the GPS APR switch will indicate an
‘ARM’ status. The ‘Need pres- press NAV’ message will also appear.
To fly the GPS approach (without radar vectors):
1. Confirm that the GPS APPR switch indicates an ‘ARM’ status. The CDI scale will begin a
steady transition from the 5.0 nm to the 1.0 nm scale as you make your way to the FAF. If
the approach has been disarmed and the aircraft is within 3 nm of the FAF, the GNC 300
will prompt you to rearm the approach.
2. Enter the altimeter setting at the destination airport on the position page when the ‘Need
pres- press NAV’ message appears.
3. The GNC 300 will automatically sequence to each waypoint in the approach, with CDI,
course and timing guidance to each waypoint. For each waypoint in the approach, the
GNC 300’s turn anticipation and waypoint alerting features will provide three pilot cues:
a. The waypoint annunciator will flash approximately 15 seconds before reaching the
turning point for each approach waypoint, and glow steadily approximately 2 seconds
prior to the turn anticipation point.
b. The ‘Next dtk’ prompt will flash in the CDI field when the ‘WPT’ annunciator begins
flashing. Set the HSI course select to the next dtk value when the waypoint annuncia-
tor starts flashing. Start the turn when the annunciator glows steadily.
c. The To/From indicator flag on the GPS CDI will flip momentarily to indicate you have
transitioned to the next approach leg.
For more information on turn anticipation and waypoint alerting, please refer to Section 5.
4. If a procedure turn is required:
a. 2 miles prior to crossing the waypoint outbound, set the GPS SEQ switch to HOLD.
b. At the waypoint, set the outbound course on the HSI.
(continued on next page)
80
APPROACH NAVI-
GATION
Approach Select
SECTION
6
APPROACH NAV
Flying the Approach
NEED PRES - PRESS NAV
The altimeter setting of the destination airport
needs to be entered on the position page.
IMPORTANT! Entering an incorrect altimeter
setting will directly affect the GNC 300’s ability to
provide accurate navigation guidance.
Enter the altimeter setting on the position page.
300 7/14/98 8:50 AM Page 80