Beechcraft C-12C Operator And Technical Reference Manual page 522

TM 1-1520-218-10
Figure 3C-119. Pilot Position Page
Table 3C-80. Pilot Position Page Procedure
NO. FUNCTION/DESCRIPTION
1 Pressing PSN function key will access the
pilot position page.
2 Computed magnetic variation at present
position.
3 This line select key is non-operational if a
computed wind speed is available or if the
FMS is displaying
Otherwise, the following three actions will
occur.
1. Selection with a valid entry in the
scratchpad will enter the wind.
2. Selection with an empty scratchpad will
copy the wind entry into the scratchpad.
3. Selection with a – in the scratchpad will
set the wind speed to 0 knots.
4 Track displays MAG track.
Navigation source selected on pilot/copilot
5
lateral steer pages.
The status and validity of the navigational source
is indicated on the title lines of the Pilot Position
SELECTED DISPLAYED
NAV SOLUTION
GPS GPS/A/H
GPS GPS/ - /H
GPS GPS/ - / -
GPS
MODEL
3C-168
an INU
Table 3C-81. Display of Navigation Mode on Position Pages
MODE
GPS navigation data is smoothed with airspeed and heading
GPS navigation data is being smoothed with GPS groundspeed and
heading
GPS is not being smoothed with airspeed and heading data
- - - /A/H GPS is invalid; FMS is dead reckoning with airspeed and heading data
MODEL The model aircraft function is providing the navigation solution.
function is available only while on the ground.
pages. Table 3C-81 lists the indications and their
meanings.
navigation source is annunciated on the CDU.
A —NAV error annunciation and/or the HSI flag
are provided when either the status of the selected
navigation sensors has degraded or the 95% error
exceeds a threshold determined by the current flight
plan guidance mode; EN ROUTE, TERMINAL, or
APPROACH.
examine the current state of the GPS navigation
solution and compare the solution to the other on-
board navigation systems.
different navigation sensor to provide continued
guidance of the aircraft.
shows the present position output from the GPS
receiver. It also shows a 95% error figure of merit for
the probable system accuracy, given the current GPS
satellite navigational quality (satellite tracking state
and geometry) as shown in Figure 3C-120 and
Table 3C-82. If GPS/A/H is indicated on the title line,
the FMS-800 is using airspeed and heading sensor
inputs to smooth the GPS data. This is required to
have a valid bank (roll) command output to the flight
wind.
director and autopilot.
The MODE indicates the current GPS receiver
tracking/aiding mode of INIT, TEST, or NAV/PVA.
The STATE indicates the lowest tracking state of
the four primary satellite tracking channels: STATE 1
is acquisition, STATE 3 is code track only (in
jamming), and STATE 5 is code and carrier lock (no
jamming).
The number of satellites being tracked for
primary navigational purposes is displayed. Normally
four satellites are tracked to provide a fully determined
position (a four dimensional position requires four
satellites). Less than four may result in GPS's data
being invalid.
CONDITIONS FOR DISPLAY
Any automatic downgrading of the
When these alerts are provided,
If necessary, select a
(a) GPS Display. The GPS INAV page
This