Garmin G1000 Pilot's Manual page 33

GPS RECEIVER 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 on 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.
When the receiver is in the process of acquiring a 3D differential GPS solution, 3D NAV is indicated as the
solution until the 3D differential fix has finished acquisition. Satellite-Based Augmentation System (SBAS)
indicates INACTIVE. When acquisition is complete, the solution status indicates 3D DIFF NAV and SBAS
indicates ACTIVE.
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 nm for oceanic and enroute, 1.0 nm for terminal,
and 0.3 nm for non-precision 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) Use the FMS Knob to 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.
190-02692-00 Rev. A Garmin G1000 Pilot's Guide for the Piper PA-32 Saratoga
SYSTEM OVERVIEW
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