Garmin GNS 530W, Руководство и справочник пилота

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2 - NAV PAGES
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Each satellite has a 30-second data transmission
that must be collected (hollow signal strength bar)
before the satellite may be used for navigation (solid
signal strength bar). Once the GPS receiver has deter-
mined your position, the 500W-series unit indicates
your position, altitude, track and ground speed. The
GPS receiver status field also displays the following
messages under the appropriate conditions:
• Searching Sky —
The GPS receiver is searching the sky for ANY vis-
ible satellites. You are also informed of this status
with a “Searching the Sky” message.
• Acquiring Sat —
The GPS receiver is acquiring satellites for naviga-
tion. In this mode, the receiver uses satellite orbital
data (collected continuously from the satellites) and
last known position to determine the satellites that
should be in view.
• 3D Navigation —
The GPS receiver is in 3D navigation mode and
computes altitude using satellite data.
• 3D Differential Navigation— The GPS receiver is
in 3D navigation mode and differential corrections
are being used.
The Satellite Status Page also indicates the accu-
racy of the position fix, using Horizontal Figure of
Merit (HFOM), Vertical Figure of Merit (VFOM), and
Estimated Position Uncertainty (EPU). HFOM and
VFOM represent the 95% confidence levels in hori-
zontal and vertical accuracy. The lowest numbers are
the best accuracy and the highest numbers are worse.
EPU is the horizontal position error estimated by the
Fault Detection and Exclusion (FDE) algorithm, in feet
or meters.
Dead Reckoning
Dead reckoning is the process of continuing navi-
gation using your last known position and speed after
a loss of GPS navigation while on an active flight plan.
CAUTION: Navigation using dead reckoning is there-
fore only an estimate and should not be used as the
sole means of navigation. Use other means of naviga-
tion, if possible.
Dead reckoning becomes active after a loss of GPS
position while you are navigating using an active flight
plan.
A pop-up message will appear and you must clear
the message before continuing operation.
The ownship icon color is changed to yellow. The To/
From flag is removed from the CDI. The Dead Reckon-
ing annunciator (DR) appears on the left side of the
map display when GPS position is unavailable and the
unit is in Dead Reckoning mode. All external outputs
dependent on GPS position are flagged.
Terrain will be noted as not available and new terrain
advisory pop-ops will not occur. Traffic and Storm-
scope information will not be shown on the Map page,
but will continue to be available on their own dedi-
cated pages. XM weather will still be available on the
Map page.
Dead Reckoning