Garmin G1000 NXi Pilot's Manual page 37

GPS SOLUTION STATUS
The GPS solution type (ACQUIRING, 2D NAV, 2D DIFF NAV, 3D NAV, 3D DIFF NAV) for the active GPS
receiver (GPS1 or GPS2) is shown in the upper right of the 'Aux - GPS Status' Page. When the receiver
is in the process of acquiring enough satellite signals for navigation, the receiver uses satellite orbital data
(collected continuously from the satellites) and last known position to determine the satellites that should be
in view. "Acquiring" is indicated as the solution until a sufficient number of satellites have been acquired for
computing a solution.
The system will determine if messages are being received from the WAAS engine. If so, the SBAS will read
'Active'. If no messages have been received for 4 seconds and SBAS providers are enabled, the SBAS status will read
'Inactive'. If SBAS providers are disabled, SBAS status will read 'Disabled'. Note, that a fix is not required, but rather
the status is determined by communication with the WAAS engine.
RECEIVER AUTONOMOUS INTEGRITY MONITORING (RAIM) PREDICTION
In most cases performing a RAIM prediction is not necessary. However, in some cases, the selected
approach may be outside the SBAS coverage area, and it may be necessary to perform a RAIM prediction for
the intended approach.
Receiver Autonomous Integrity Monitoring (RAIM) is a GPS receiver function that performs a consistency
check on all tracked satellites. RAIM ensures the available satellite geometry allows the receiver to calculate a
position within a specified RAIM protection limit (2.0 nautical miles for enroute and 0.3 nm for approaches).
During oceanic, enroute, and terminal phases of flight, RAIM is available nearly 100% of the time.
The RAIM prediction function also indicates whether RAIM is available at a specified date and time. RAIM
computations predict satellite coverage within ±15 min of the specified arrival date and time.
Because of the tighter protection limit on approaches, there may be times when RAIM is not available. The
system automatically monitors RAIM and warns with an alert message when it is not available. If RAIM is not
predicted to be available for the final approach course, the approach does not become active, as indicated by
the messages "Approach is not active" and "RAIM not available from FAF to Map". If RAIM is not available
when crossing the FAF, the missed approach procedure must be flown.
NOTE: The system RAIM prediction capability does not meet all RAIM prediction requirements. Reference
the RAIM/Fault Detection and Exclusion (FDE) Prediction Tool at flygarmin.com as required.
Predicting RAIM availability at a selected waypoint:
1) Select the 'Aux - GPS Status' Page.
2) If necessary, press the RAIM Softkey.
3) Push the FMS Knob. The 'Waypoint' Field is highlighted.
4) Turn the small FMS Knob to display the 'Waypoint Information' Window.
5) Enter the desired waypoint:
Use the FMS Knob to enter the desired waypoint by identifier, facility, or city name and press the ENT Key.
Or:
190-02177-02 Rev. A
Garmin G1000 NXi Pilot's Guide for the Cessna NAV III
SYSTEM OVERVIEW
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