II Morrow Inc. NMC 2001 Operating Manual page 281

Operations
preceded by Approach Active in the event of a missed approach or a
canceled approach.
An approach is enabled by pressing ENT when the "Enable
Approach?" prompt is displayed. Note that there are two methods to
enable an approach:
Approach
to Active
Flight Plan
Method 1
Press ENT when the "Enable Approach?" prompt is displayed as a
message. The message will occur when an approach is loaded from the
database and the aircraft is 30 nm or less from the destination airport.
This message-prompt is repeated at 3 nm inbound to the FAF if the
approach has not yet been enabled.
Method 2
When an approach has been loaded, the aircraft is less than 30 nm from
the destination airport, and the approach has not yet been enabled,
pressing FPL will result in displaying the "Enable Approach?"
prompt. Press ENT when this prompt is displayed to enable the
approach.
Enroute Operation
CDI Scale = 5nm
Load
Approach Operations
30nm to
Airport
MSG
Annunciator
Flashes.
Enable
Approach?
Press ENT
and then
Enter Local
Altimeter
Setting
265