787 Flight Crew Operations Manual
DO NOT USE FOR FLIGHT
Flight Management, Navigation -
Navigation Systems Description
Copyright © The Boeing Company. See title page for details.
11.20.12 D615Z003-TBC
ADF Displays
Left and right ADF bearings are automatically displayed on the PFD mini-map
when manually tuned through the CDU. ADF data is cyan.
In the unlikely event that all three FMCs fail, or if all of the large displays fail, ND
map displays blank and the ADFs become unusable. Aircrews must revert to
navigation using the alternate navigation (ALTN NAV) function of the TCP.
Distance Measuring Equipment (DME)
Two DME systems are installed. The DMEs are usually tuned by the FMC, but
may be tuned manually.
DME Tuning
DME is tuned manually when the VOR portion of a VOR/DME pair is entered on
the NAV RADIO page. The FMC tunes DME as necessary for radio position
updates. Manual DME tuning does not inhibit FMC DME tuning.
The FMC uses two DMEs for position updates. DME/DME position updates are
usually more accurate than VOR/DME updates. The FMC cannot tune specific
DMEs if the navaids are inhibited on the REF NAV DATA page.
DME Displays
DME distances are displayed on the ND map when VOR L or VOR R are selected
on the ND drop-down menu. DME distance also displays on the PFD when the
ILS receivers are tuned to a collocated DME and localizer facility.
POS REF page 2/4 displays the identifiers of the DME stations used for FMC
position updates.
Instrument Landing System (ILS)
Two ILS receivers are installed. They are usually tuned by the FMC, but can be
tuned manually on the NAV RADIO page.
ILS Tuning
Two conditions must be met for FMC ILS autotuning to occur:
• an ILS, LOC, back course, LDA (localizer–type directional aid), or SDF
(simplified directional facility) approach have been selected to the active
route, and
• the airplane is within 50 NM from the top of descent, 150 NM of the
destination airport, or the FMC is in descent mode
Both ILS receivers can be manually tuned from the NAV RADIO page at anytime
unless ILS approach tuning inhibit is active.
February 15, 2010
To Next Page
Loading...
