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Section 2 System Overview
2-40
IDU-450 EFIS Software Version 8.0H (Rotorcraft)
1
st
Ed Nov 2018
2.5.7 Audio-Only Caution and Advisory Alerts
Table 2-13: Audio-Only Caution and Advisory Alerts
Caution or
Advisory Alert
Voice Alert/
Alert Tone
Condition
** No time delay
Minimum Altitude
Caution Alert
“Minimums,
Minimums”
Deviation from above to below
minimum altitude bug. Minimum
altitude readout turns amber (yellow)
and flashes. **
Selected Altitude
Deviation
Caution Alert
“Altitude,
Altitude”
Deviation greater than 150’ from
selected altitude after capture (within
100’ of altitude). 2-second time delay.
VNAV Altitude
Deviation
Caution Alert
If not on a descending VNAV profile,
deviation greater than 150’ from
altitude of the current or prior VNAV
waypoint after capture (within 100’ of
altitude). 2-second time delay.
Decision Height
Caution Alert
“Decision
Height”
Deviation from above to below
decision height bug. Decision height
readout turns amber (yellow) and
flashes. **
GBS/SBAS
Failure
Caution Alert
Alert Tone
No valid position data available from
selected GPS/SBAS for more than 5
seconds and dead reckoning not
available. Inhibited during and for 10
seconds after unusual attitude mode.
Loss of position data is obvious from
symbology changes associated with
reversionary modes.**
GPS/SBAS Loss
of Integrity
Caution Alert
Alert Tone
GPS/SBAS loss of integrity caution.
Inhibited during and for 10 seconds
after unusual attitude mode. LOI
indication is integrated with lateral
deviation indicator. **
GPS/SBAS Loss
of Navigation
Caution Alert
Alert Tone
GPS/SBAS loss of navigation
caution. Inhibited during and for 10
seconds after unusual attitude mode.
LON indication is integrated with
lateral deviation indicator. **