Section 3 Display Symbology
3-30
IDU-450 EFIS Software Version 8.0H (Rotorcraft)
1
st
Ed Nov 2018
3.3.23. Heading/Roll-Steering Sub-Mode
Heading/roll-steering sub-mode annunciation appears immediately right of
the selected navigation source annunciation and displays:
1) HDG:
LVL
(Wing-Leveling Sub-Mode Guidance)
2) HDG:
LNAV
(LNAV Sub-Mode Guidance)
3) HDG:
BUG
(Heading Bug Sub-Mode Guidance)
4) HDG:
---
(Failure Sub-Mode)
3.3.24. Heading Bug Sub-Mode
The heading bug sub-mode is active when selected through the menu
system and commands roll angles to track the heading bug with aircraft
heading (if heading is valid) or aircraft track (if heading is invalid). Figure
3-52 shows this mode with positive feedback from the autopilot (green
annunciation and filled heading bug).
LNAV (L1)
is a one-touch method for
turning off the HDG bug and engaging in LNAV mode.
Figure 3-52: Heading Bug
Figure 3-53: LNAV Armed Mode