Eventide ARGUS 5000 - Page 63

CDI in Flight Plans
In GPS flight plan (or leg) mode, the triangle operates differently. As you pass one
waypoint, the GPS automatically switches to the next one. Therefore, you are always
going TO a waypoint and the triangle always points up. It might briefly reverse as you
pass one waypoint for the period it takes the GPS to activate the next one, or if you
pass too far from the waypoint for the GPS to recognize it and make the appropriate
leg change.
Remember, just as with a VOR with OBS, the direction of flight is irrelevant. It is
your position with respect to the facility that determines the direction of the pointer
triangle.
Waypoints and Courselines in the Argus PLAN MODE
312° BRG TK 159 KTS
.8 NM 120° 00:00=18
TEB
29EH1
L10°TE
DEP/2
The Argus PLAN mode autoranges to encompass your
destination, or, in the case of multiple waypoints, the
farthest one. The maximum distance that can be shown in
PLAN is 9999 nm from your present position. If
courselines are selected, they will be drawn between on
screen waypoints as appropriate.
Great Circles in Plan Mode
The Argus performs its navigation by using Great Circles.
This is the same method that is used by the vast majority
of GPS and LORAN units. In even the longest enroute
range (240 nm) the difference between a Great Circle and
a straight line (rhumb line) is invisible. However, the
maximum range of the plan mode is 9999 nm. On a 9999
nm display the range ring is only 800 nm short of the opposite side of the Earth. At
this range the difference between Great Circles and rhumb lines becomes dramatic. In
order to present the clearest and most useful display to the pilot, the Argus draws the
plan mode as a "Great Circle Projection." What this means is that a "straight" line
from the aircraft symbol to any waypoint on the screen will actually be the shortest
distance Great Circle bearing to that waypoint.
Passed Waypoint
Triangle shows FROM
July 1999 Argus 5000/7000 Ver. 5.xx Reference Manual Part#141003 55