Embraer EMB145 - Page 2265

AIRPLANE
OPERATIONS
MANUAL
NAVIGATION AND
COMMUNICATION
REVISION 31
2-18-11
Page
7
Code
01
NAV OPERATION
The NAV operation is identical to the COM operation. However, NAV
controls are accomplished by actuation of the Frequency Transfer
Button and the Line Select Button located on the upper RH of the RMU
Bezel Panel. Furthermore, the NAV window has an additional function
called DME Split Tuning Mode. The operation in the DME Split Tuning
Mode is similar to the operation in the DME Hold Mode.
The NAV system also incorporates FMS auto-tuning capability.
Through the NAV Memory Page it is possible for the FMS to perform
automatic tuning of the navigation radios (raw data) along the route by
pressing the upper RH Frequency Transfer Button, which enables or
disables the FMS auto-tuning capability. When the VOR or the ILS
frequency is auto-tuned by the FMS, a magenta VOR or ILS frequency
and a magenta AUTO label will be displayed on the top border of the
RADIO Page NAV window.
DME OPERATION
In normal DME operations only one of the six DME channels is paired
with the VOR active frequency and one other with the preset VOR
frequency. However, pressing the DME Select Button, labeled DME,
on the RMU Bezel Panel, will enable the DME to be tuned
independently of the VOR active frequency.
Pressing the DME Select Button once will cause the NAV window to
split into two windows. The top window will display the active VOR
frequency and the lower window, with the DME label, will display the
active DME frequency in VHF format. When the NAV window is split,
an H (DME Hold) label is displayed in the DME window to indicate that
the DME is not paired with the active VOR/ILS frequency. In this case
the DME hold condition will also be announced on the PFD. In this
condition, the DME may be tuned directly by simply pressing the
associated Line Select Button beside the DME window and tuning the
new DME channel through the Frequency Tuning Knobs.
Pressing the DME Select Button again will cause the frequency to be
displayed in the channel format (TACAN).
Pressing the DME Select Button for the third time will cause the NAV
window to resume its normal mode with the active and preset
frequencies being displayed while returning the DME to the condition of
channeling with the active VOR frequency.