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Section 4 Reversionary Modes
4-4
IDU-450 EFIS Software Version 8.0H (Rotorcraft)
1
st
Ed Nov 2018
Note 1:
Presented using inertial dead-reckoning based on last known
wind information. If unable to dead reckon (e.g., heading is
failed or true airspeed cannot be calculated), function is
disabled.
Note 2:
Only radar altitude presented when available.
Note 3:
Last known wind is saved during GPS/SBAS failure.
Note 4:
Either radar altitude or geodetic altitude less database
elevation.
Note 5:
Waterline symbol expanded to large attitude bars. Rotorcraft
versions (Part 27 or Part 29 airspeed scale), use full-time large
attitude bars and do not show the waterline symbol.
Note 6:
Special use airspace boundaries are drawn with bold lines due
to lack of aircraft altitude data.
Note 7:
In heading-only failure mode or AHRS failure mode, heading
scale aligned with aircraft track and heading indication is
removed. In heading-only failure mode or AHRS failure mode
combined with GPS failure, heading scale is replaced with a
red-X.
Note 9:
In heading-only failure mode or AHRS failure mode, compass
rose aligned with aircraft track and heading indication is
removed when in heading up mode. In heading-only failure
mode or AHRS failure mode combined with GPS failure,
compass rose is removed.
Note 10:
Presents using last-known wind information and aligned with
aircraft track in heading up mode.
Note 11:
Only radar altitude presented when available.
Note 12:
Assuming valid fuel flow information, endurance is presented.
Note 13:
Large attitude bars presented and X’d out.
Note 14:
Flight path marker grayed after 1 minute to indicate degraded
operation.
Note 15:
Highway in the Sky removed after 1 minute.
Note 16:
See IDU SCC Card and Limits Requirements for activation
requirements.
Note 17:
Defaults to AIR unless Weight on Wheel/Weight on Ground
discrete input is active.