Garmin GPS 400 Pilot's Manual And Reference page 49

Selecting a Destination from the Active Flight Plan
If you're navigating an active flight plan, any waypoint contained in the flight
plan may be selected as a direct-to destination from the select direct-to waypoint
page. (See section 3, beginning on page 44, for more information on flight plans.)
To select a direct-to destination from the active flight plan:
D
d
E
Selecting the Nearest Airport as a Direct-To Destination
The select direct-to waypoint page always displays the nearest airports (from
your present position) on the NRST field. Navigating directly to a nearby airport is
always just a few simple steps away. (Nearby airports may also be selected as
direct-to destinations using the steps described on page 103.)
To select a nearby airport as a direct-to destination:
D
d
E
a
a
E
a
a
E
DIRECT-TO
Flight Plan Waypoints
Nearest Airports
2

a
Ž
a
Ž
b