BendixKing KLN 900 - Pilots Guide - Manual (Page 142)

5-35 Rev 2
The following procedure can be used to switch modes
when an external LEG/OBS switch is installed in the air-
craft:
1. Locate the external switch in the panel of the aircraft.
An example of an external switch annunciator is
shown in figure 5-112.
2. Change the position of the external switch. In the case
of the combination switch/annunciator all that you
have to do is press the switch and it will change
modes (figure 5-113).
5.9.2 The Leg Mode
The following are characteristics of the Leg Mode:
1. The default course deviation indicator (CDI) sensitivity
is plus and minus five nautical miles, full scale. This
applies to the CDI on the NAV 1 page as well as any
external CDIs or HSIs interfaced to the KLN 900. If
the CDI or HSI has five dots left and right of the center
position, then each dot represents one nautical mile of
deviation.
NOTE: In some installations where the KLN 900 is
interfaced to certain models of EFIS equipment, the scale
factor will be plus or minus 7.5 nautical miles, full scale.
Refer to the Flight Manual Supplement for the aircraft or
the Pilot’s Guide for the EFIS equipment for details.
2. Navigation is provided along the great circle path
between two waypoints. As you probably know, great
circle navigation is the shortest distance between two
points located on the earth’s surface. In the case of
Direct To operation, the “from” waypoint is not
displayed but it is the point where Direct To operation
was initiated. The course to fly while in this mode is
referred to as the desired track (DTK). The desired
track is displayed on the NAV 3 and D/T 3 pages. You
can also configure the Super NAV 5 page to display
desired track, see section 3.9.7. To fly a great circle
course between two points, the desired track may be
constantly changing. A good way to illustrate this
concept is with a world globe and a piece of string.
You can determine the great circle path between
Denver, Colorado and Manila, Philippines by stretch-
ing the string over the globe between these two
points. Notice that you would start the flight with a
Northwesterly desired track, which gradually becomes
due Westerly, and finally Southwesterly by the time
you reach Manila. Of course, your trips with the KLN
900 will be substantially shorter and the desired track
will probably change only a few degrees.
Figure 5-112
GPS CRS
LEG
GPS CRS
OBS
Figure 5-113