AlliedSignal Bendix/King KLN 89, Руководство пилота

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Basic GPS Operation
3-38
Basic GPS Operation
Chapter 3
Line 3: Magnetic desired track, and magnetic actual track (see
Appendix A for navigation terms). In normal on-course flight, it is
desirable to steer the aircraft to keep these two numbers equal.
Line 4: A cyclic field which can display either bearing to the active
waypoint (To), radial from the active waypoint (Fr), or the VNAV sta-
tus, which will either by Off, Armed, time until VNAV begins, or the
suggested VNAV altitude (see
section 4.4 ). By placing the cursor
over this field and pressing the
E
button, you may toggle between
the three options.
NOTE: Due to “great circle” courses and magnetic variation differ-
ences between present position and the active waypoint, the To
bearing and From radial may not be exactly 180° different from each
other when the system is in the Leg mode. This condition is most
likely to occur when long distances are involved, and/or you are
operating in very northerly or southerly latitudes. See figure 3-118 for
an example depicting a case like this. The aircraft is somewhere over
Georgia, and the active waypoint is KPHX. The bearing to steer is
269°, and radial is 72°. Generally, you will want to use bearing (not
radial) when long distances are involved.
Line 4 also displays the estimated time en route (ETE) from present
position to active waypoint.
N
N
KPHX
72
°
269
°
Figure 3-118