PFD Operation
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SkyView Pilot’s User Guide - Revision M
GPS Assist
In the event of airspeed loss (due to icing or other blockage) an accurate attitude is maintained
if there is an accurate GPS ground speed source.
When in this mode, a magenta GPS ASSIST
message is displayed on the PFD and the ground speed is displayed below the indicated
airspeed (IAS). If the connectivity with the GPS fails while in GPS assist mode, the attitude
continues to be displayed, using the last known GPS ground speed as a reference. This mode is
flagged on the horizon with a yellow CROSS CHECK ATTITUDE message. In the very rare case
that this sequence of events occurs, the ADAHRS’ attitude accuracy is reduced; use other
references in the aircraft to cross-check against the SkyView display.
Note that due to a limitation of the SV-GPS-250 hardware, it cannot be used for GPS Assist
above 415 knots ground speed if it is being used as the GPS source
Flight Path Marker
The flight path marker as shown in Figure 14 is an icon that is superimposed on
the PFD. It depicts the actual trajectory that the aircraft is flying through space. In
contrast, the attitude indicator displays the direction that the aircraft is pointed.
The flight path marker is extremely helpful in correlating and distinguishing
between aircraft attitude and flight path, giving the pilot a better understanding
of what the aircraft is doing. Given this, the marker can also be a valuable aide
for avoiding terrain when used with Synthetic Vision.
The flight path marker can be enabled or disabled through the setup menus. See the SkyView
Installation Guide for information about this setting.
Several examples of Flight Path Marker behavior:
If the aircraft’s nose is pitched up, but the marker stays on the horizon, this indicates
that the aircraft is not climbing or descending. You will see this behavior during slow
flight.
If the aircraft is neither climbing nor descending, the flight path marker will align with
the zero pitch line. Many aircraft do not cruise at an exactly level attitude. In this case, it
is normal to have a slightly pitched up or pitched down attitude indication, even though
the flight path marker indicates the aircraft is indicating no vertical trajectory.
If the marker is to the left or right of the attitude indicator’s aircraft symbol, this
indicates that the path over the ground is different than the direction the aircraft is
pointing. This depicts the effects of wind or a slip attitude.
If the aircraft is climbing out of a canyon and the marker is above the terrain ahead, this
indicates that the aircraft, at its current trajectory, will clear that terrain.
If the aircraft is climbing out of a canyon and the marker is overlaid on the terrain
ahead, this indicates that the aircraft, at its current trajectory, will impact the terrain.
If the marker is pointed at a runway threshold during an approach, that is where you will
be when you land if you keep the same approach path to the runway.
Figure 14–
Example Flight
Path Marker
