Cockpit Reference Guide

Garmin G1000 Cockpit Reference Guide for the Cessna Nav III

190-00384-12 Rev. A

SECTION 6 – AUTOMATIC

FLIGHT CONTROL

6-21

Intercepting and Flying a DME Arc

The AFCS will intercept and track a DME arc that is part

of the active ﬂight plan provided that GPS Navigation Mode

is engaged, GPS is the active navigation source on the CDI,

and the DME arc segment is the active ﬂight plan leg. Since

navigation of DME arcs is based on GPS, when the APR Key

is pressed and LOC or VOR Approach Mode is armed prior

to reaching the Initial Approach Fix (IAF), Approach Mode

will not activate until the arc segment is completed.

If the arc is intercepted at a location other than the

published IAF (i.e. ATC provides vectors to intercept the arc)

and subsequently Heading Mode or Roll Mode is selected,

the AFCS will not automatically intercept or track the arc

unless the arc leg of the ﬂight plan is activated GPS Navigation

Mode is armed. The AFCS will not intercept and ﬂy a DME

arc before reaching an IAF that deﬁnes the beginning of the

arc segment. Likewise, if at any point while established on

the DME arc GPS Navigation Mode is deselected, the AFCS

will no longer track the arc.

Figure 6-25 Backcourse Mode

LOC2 is Selected Navigation Source

Command Bars Hold Pitch Attitude

Pitch Hold

Mode Active

Backcourse

Mode Active

Backcourse Mode (BC)

NOTE: When making a backcourse approach,

set the Selected Course to the localizer front

course.

Backcourse Mode captures and tracks a localizer

signal. The mode may be selected by pressing the BC

Key. Backcourse Mode is armed if the CDI is greater than

one dot when the mode is selected. The ﬂight director

creates steering commands from the Selected Course and

deviation when in Backcourse Mode.

Changing the Selected Course

The Selected Course on the PFD is controlled using the

CRS Knob. Pressing the CWS Button and hand-ﬂying

the aircraft does not change course while in Backcourse

Mode. The autopilot guides the aircraft back to the

Selected Course when the CWS Button is released.