TM 1-1510-225-10
3D-42
Figure 3D-56. Approach Sequence
(1) Select and Load the Approach Into the
Flight Plan. This can be done at almost anytime, but
must be completed before reaching the final approach
fix and should be done as soon as possible (position
A). If the aircraft is greater than 30 nm from the
airport, the CDI scale factor will remain at the default
± 5.0 nm full scale deflection.
(2) Transition to the Approach Arm Mode.
This will occur automatically when the aircraft is within
30 nm of the airport and there is an approach loaded
into the flight plan (position B). The CDI scale factor
will change to ± 1.0 nm over the next 30 seconds and
the external annunciator will indicate ARM.
(3) Get Established on the Final Approach
Course.
1. No PT arrival route.
2. Radar vectors (requires OBS mode).
3. Procedure turn or holding pattern
(requires OBS mode).
4. DME arc.
(4) Transition to the Approach Active Mode.
This mode change is automatic and occurs at position
C when:
1. The aircraft is 2 nm from the FAF and
the approach mode is armed.
2. The LEG mode is selected.
3. The aircraft is heading towards the
FAF.
4. The FAF or a co-located IAF/FAF is
the active waypoint.
5. The KLN 90B confirms that adequate
integrity monitoring is available to
complete the approach.
(5) If any of these conditions are not met, the
KLN 90B will not transition to the approach active
mode and a missed approach will be required if the
conditions do not change before reaching the FAF. If
all of these conditions are met, the CDI scale factor will
start to change to ± 0.3 nm and the external
annunciator will indicate ACTV.
(6) At the FAF (position D), the CDI scale
factor will be at ± 0.3 nm and will remain at this scale
factor until the approach mode is canceled by pressing
the external GPS APR button to change to the ARM
mode, by initiating a direct to operation, or by changing
to the OBS mode.
It is not approved to conduct the final
portion of the approach unless the KLN
90B is in the approach active mode.
(7) Fly to the missed approach point (position
E). The KLN 90B will not automatically sequence to
the next waypoint, it must be manually selected. By
default, the KLN 90B will nominate the first waypoint of
WARNING
