AFCS System

Question 1

Simplex Failure

Answer 1

Indications - increase in motion, tip path plane movement, AFCS DEGRADED and all fail advisory lights except DSENS and SAS

1. AFCS and TRIM - secure
2. Computer power - off then on
3. AFCS and TRIM - on

If computer fails to reset
4. Check circuit breakers

Question 2

Duplex Failure

Answer 2

Indications - increase in aircraft movement, vibration, tip path plane moving, AFCS caution light

1. Computer power - off then on

If AFCS caution light does not extinguish

2. IMC - land as soon as possible
3. VMC - land as soon as practical

Question 3

AFCS Inner/Outer Loop Failure

Answer 3

Indications - shudder, ucommanded change in aircraft attitude, momentary uncommanded flight control movement

1. AFCS pushbutton - off
2. TRIM pushbutton - off
3. IMC - land as soon as possible
4. VMC - land as soon as practical

Question 4

AFCS Servo Hardover

Answer 4

1. Transfer to the other AFCS servo
   
   • CAUTION - high control forces may change to normal if AFCS servos are transferred
2. If servo hardover condition goes away - land as soon as practical
3. If hardover condition persists - secure AFCS servo
4. IMC - land as soon as possible
5. VMC - land as soon as practical