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System Overview
FULL-TIME ENVELOPE ALERTING (EA
™)
NOTE
Envelope Alerting Requires Flap Input
For the underspeed Full-Time Envelope Alerting
(EA
™) function to be available when the autopilot is
in standby (“AP Ready”), a wiring modification must
be made that allows the autopilot to recognize
actual flap position. Not accomplishing this wiring
modification to the aircraft harnessing means there
is no Full-time Envelope Alerting (EA
™) for
underspeed conditions when the autopilot is in
standby mode. The underspeed Full-Time Envelope
Alerting (EA
™) function is not available when flaps
are set to full in non-primary engine (
“SIU”)
equipped Cirrus or any Aspen-equipped aircraft.
The DFC90 autopilot provides speed-based and attitude-based
envelope alerting when the autopilot is not engaged (servos not
coupled). [Requires Avidyne PFD Rel 8.0.4 or Aspen PFD v2.6
and DFC90 Rel 2 or later.]
Full-time Envelope Alerting (EA
™) is triggered when the DFC90
recognizes an underspeed (Underspeed EA function is not
available in SIU-equipped Cirrus or any Aspen-equipped aircraft
when flaps are set to full), overspeed, flap overspeed or
excessive bank angle condition and will alert the pilot via text
alerts on the PFD and aural alerts.
Full-time Envelope Alerting (EA
™) is provided during flight
director operations (servos not coupled). Full-time Envelope
Alerting (EA
™) is also provided (underspeed requires the flap
wiring modification) even when the autopilot and flight director are
off and the autopilot is in the standby position as noted by the
AP
READY
mode annunciator on the top strip of the PFD.
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