R Bearing/Distance to a Fix Figure 007
R 1EFF : 106-149, 151-199, 211-299, 301-399, 1 22-72-00Page 16 1401-499, 1Config-2 Aug 01/05 1 1 1CES 1 A manual updating is possible on the PROG page under the prompt UPDATE AT (Ref. Fig. 008) The updated position can be inserted through a LAT/LONG, a PLACE/BEARING/DISTANCE, a PLACE.BRG/PLACE.BRG, a waypoint ident, a navaid or NDB ident or an airport ident into 5L. The updating is initiated by a push on 5R line select key. Automatic updating is provided:
-At takeoff when the takeoff thrust is applied and if the current navigation mode is not GPS/INERTIAL. The updated position is the runway threshold coordinates modified by the runway shift inserted on the TAKEOFF page if any (Ref. Fig. 009)
R Position Updating Figure 008
R 1EFF : 106-149, 151-199, 211-299, 301-399, 1 22-72-00Page 18 1401-499, 1Config-2 Aug 01/05 1 1 1CES 1
Runway Take-off Shift for Takeoff Position Updating
Figure 009
B. Navigation Mode Selection and Class of Navigation
(1)
General When GPS is installed, GPS/INERTIAL is the basic navigation mode, provided GPS data are available with required accuracy and integrity. Otherwise, a navigation mode with the least errors is chosen based upon the best position available as defined in this Para. B and C. The basic modes of navigation are the following: . GPS/INERTIAL . DME/DME/INERTIAL . DME/VOR/INERTIAL . INERTIAL ONLY The mode chosen is as defined in Para. 2.A. If an IRS position is available, one of the modes is used. Else, no navigation computation is provided. As well as mode annunciation, navigation supplies data for class annunciation; this announcement depends upon the navigation uncertainty and the navigation mode (Ref. Para. (3)).
(2)
Navigation mode selection
(Ref. Fig. 010)
(a) GPS/INERTIAL
1 Hybrid architecture (selected via OPC)
_ R If a valid and reasonable hybrid GPIRS position is available R from one of the IRS's and if it provides the best accuracy
solution than any other sensor (based on sensor EPE), the
GPS/INERTIAL mode is chosen. R The logic to determine the availability of the hybrid GPIRS R position will take into account the hybrid factor of merit
delivered by the IRS. The logic to determine the reasonableness of the GPIRS position will take into account the hybrid integrity monitoring data delivered by the IRS. In case of hybrid integrity monitoring unavailability, an equivalent reasonableness test using pure IRS data will be performed. Since GPIRS hybrid position is very accurate and, for all practical purposes, is nearly identical across the 3 ADIRS inputs, the FM will only use one input of GPIRS hybrid position for computing FM position. The availability of 3 hybrid GPIRS positions will result in a single hybrid position based on normal IRS selection priority: OWN, 3, OPP. No GPIRS position mixing is necessary.
Navigation Mode Selection
Figure 010
The FMS position will be a mix of the hybrid GPIRS position
and the mixed IRS position and the navigation mode displayed
on the POSITION MONITOR page will be "N IRS/GPS", with N being
the number of IRS's used to compute mixed IRS position.
The selected hybrid GPIRS position is displayed on the
POSITION MONITOR page in place of radio position.
The mixed IRS position and the IRS deviations displayed on
Position Monitor page will not change and will still be
computed using pure IRS inputs.
The GPS/INERTIAL mode will be inhibited if pilot deselects GPS
through the Selected Navaids page.
2_ Autonomous architecture (selected via OPC)
If a valid and reasonable autonomous GPS position is available
from one of the GPS's and if it provides the best accuracy
solution than any other sensor (based on sensor EPE), the
GPS/INERTIAL mode is chosen.
R The logic to determine the availability of the autonomous
R GPIRS position will take into account the autonomous factor of
merit delivered by the GPS.
The logic to determine the reasonableness of the GPS position
will take into account the autonomous integrity monitoring
data delivered by the GPS.
In case of autonomous integrity monitoring unavailability, an
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