High Or Low Voltage On Essential Bus; Ess Bus Warning; Integrated Avionics System; Attitude & Heading Reference System (Ahrs) Failure - Cirrus SR20 Checklist

C I R R U S

High or Low Voltage on Essential Bus

ESS BUS Warning

1. Essential Bus Voltage (ESS) ..............................................CHECK
If Essential Bus Voltage is greater than 32 volts:
2. Main Bus 1 and Main Bus 2 Voltages (M1 and M2)............CHECK
3. Perform appropriate M Bus 1 or M Bus 2 Warning checklists.
If Essential Bus Voltage is less than 24.5 volts:
4. Perform Alt 1 Caution (Failure) and Alt 2 Caution (Failure)
checklists.
If unable to restore at least one alternator:
5. Non-Essential Loads ....................................................... REDUCE
a. If flight conditions permit, consider shedding:
Air Conditioning, Landing Light, Pitot Heat, Cabin Fan, Nav
Lights, Strobe Lights, Audio Panel, COM 2
6. Land as soon as practicable (Battery reserve only).

Integrated Avionics System

Attitude & Heading Reference System (AHRS) Failure
1. Verify Avionics System has switched to functioning AHRS
If not, manually switch to functioning AHRS:
2. Failed ADAHRS Circuit Breaker .............................................. SET
If open, reset breaker. If circuit breaker opens again, do not reset.
3. Be prepared to revert to Standby Instruments (Altitude, Heading)

Air Data Computer (ADC) Failure

1. Failed ADAHRS Circuit Breaker .............................................. SET
If open, reset (close) circuit breaker. If circuit breaker opens again,
do not reset.
2. Revert to Standby Instruments (Altitude, Airspeed).
3. Land as soon as practicable.

PFD Display Failure

1. Display Backup ...............................................................ACTIVATE
2. Land as soon as practicable.
P/N 11935-006
March 2017
P I L O T ' S C H E C K L I S T
ESS BUS
EMERGENCY
M O D E L S R 2 0
E - 11