190-00709-05 Rev. D
Garmin G1000 Pilot’s Guide for the Socata TBM 850/900
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SYSTEM OVERVIEW
The current calculated GPS position, time, altitude, ground speed, and track for the aircraft are displayed
below the satellite signal accuracy measurements.
• 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 in the upper right of the 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. SBAS (Satellite-Based Augmentation System)
indicates INACTIVE. When acquisition is complete, the solution status indicates 3D DIFF NAV and SBAS
indicates ACTIVE.
• RAIM (Receiver Autonomous Integrity Monitoring) Prediction (
RAIM
Softkey is selected)
In most cases performing a RAIM prediction is not be 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 that the available satellite geometry allows the receiver to
calculate a position within a specified RAIM protection limit (2.0 nautical miles 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
G1000 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.
Predicting RAIM availability
1)
Select the GPS Status Page.
2)
If necessary, select the
RAIM
Softkey.
3)
Press 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:
a)
Use the
FMS
Knob to enter the desired waypoint by identifier, facility, or city name and press the
ENT
Key. Refer
to Section 1.7 for instructions on entering alphanumeric data into the G1000.
Or
:
