AFCS/Autopilot

Question 1

What is the purpose of SAS (Stability Augmentation System)?

Answer 1

dampen disturbances due to dynamic mode, atmospheric disturbances, etc.

SAS provides stabilization in pitch, yaw, and roll, but not control

Question 2

What are the 5 levels of AFCS control?

Answer 2

1. Unstabilized
2. Backup SAS
3. Digital SAS
4. Autopilot - Attitude Retention
5. Autopilot - Upper Modes

Question 3

What do the upper modes provide?

Answer 3

navigation and instrument approaches

Question 4

How many SEMAs are used in P/R/Y for back-up SAS?

Answer 4

3. 1 in each axis.

Question 5

What sensors are used for Digital SAS?

Answer 5

2 AHRS sensors for P, R, Y

2 APMs

Question 6

What is the purpose of the SAS/AP CUT switch?

Answer 6

disengage both back-up SAS and AFCS simultaneously

Question 7

What does the basic AFCS structure consists of?

Answer 7

1. Sensors that measure relevant data
2. Comtation unit that analyzes received data and computes control signals
3. Actuators that vonvert contorl signals from computation to physical control movement

Question 8

What is the purpose of the AHRS?

Answer 8

generate and compute attitude (pitch, roll, and gyro-magnetic heading) angular speed and linear acceleration in 3 axis.

Question 9

Where are the autopilot modules located?

Answer 9

pelican rack

Question 10

What is the total SEMA equivalent control authority (both actuators) for pitch, roll, and yaw axis?

Answer 10

P- 11%
Y- 12%
R- 18%

Question 11

What should be the immediate action step when the red AP warning light is illuminated?

Answer 11

Hand on the controls

Question 12

What does the YAW SAS caution light indicate?

Answer 12

failure of the YAW SAS, failure of the yaw FOG, and/or yaw SEMA

Question 13

where are the emergency and malfunction procdures found for the AFCS/autopilot?

Answer 13

Chapter 9