ATA 22 - Autoflight

Question 1

Which units are included in the Autoflight System?

Answer 1

• 1 ea Autopilot Panel (APP)
• 1ea (or 2 ea) Mode Select Panel
• 1 ea Flight Control Computer (FCC)
• 3 ea Servos (Aileron, Rudder & Elevator)

Question 2

What do the TURN Knob on the Autopilot Panel (APP) do?

Answer 2

It is used to manually
apply roll commands to the autopilot.

(If the autopilot is engaged, moving the TURN knob from detent resets the lateral mode to HDG (heading)
mode, except in APPR (approach) mode, and slews the heading reference indicated by the heading bug on
the EHSI)

Question 3

What do the Pitch Knob on the Autopilot Panel (APP) do?

Answer 3

It is used to manually
apply pitch commands to the autopilot.

(If the autopilot is engaged, moving the pitch knob from detent resets the
vertical mode to VS (Vertical Speed))

Question 4

What happens when you push the AP XFER button on the APP?

Answer 4

The button enables the transfer of command from one channel to the other (dual systems only).

Question 5

Which buttons on the MSP (Mode Select Panel) controls the lateral modes?

Answer 5

The buttons on the upper row.

(The vertical mode buttons are on the lower row)

Question 6

Which are the Lateral Modes?

Answer 6

• HDG (Heading)
• 1/2 Bank
• NAV
• APPR (Approach)

Question 7

Which are the vertical Modes?

Answer 7

• VS (Vertical Speed)
• IAS (Indicated Airspeed).
• CLIMB.
• ALT (Altitude Hold).

Question 8

Which are the Basic Modes (the ones that will be selected when the system powers up)?

Answer 8

Lateral: HDG

Vertical: VS

Question 9

Both MSPs are slaved together through the FCC

When will the two MSPs not be slaved together?

Answer 9

In APPR. The slaving function is cancelled until APPR has been de-selected on both MSPs

Question 10

Where is the Flight Control Computer (FCC) located?

Answer 10

In the avionics rack

Question 11

From where do the FCC receive inputs?

Answer 11

• Autopilot controls (APP, MSP, GA switch, A/P disconnect switch, VERT SYNC switch).
• Servo tachometers.
• AHRS 1 and 2.
• Air data system.
• EFIS. The EFIS transmits radio altitude, navigation data and ILS data to the FCC.
• Trim system.
• Flap system.

Question 12

How is an FCC failure annunciated?

Answer 12

A red FD on the EADI. Flashing in 10 seconds and then steady.

Question 13

How will the pilot know that the autopilot disconnect?

Answer 13

An aural warning (cavalry charge) & the AP annunciation on EADI turns red and flashing.
This can be acknowledged by operating the A/P disconnect switch on either control yoke.

Question 14

How many safety levels are there in the servo motor/mount for each control axis?

Answer 14

3

Question 15

How can the pilot manually disengage Autopilot?

Answer 15

• Press AP disengage button on either control wheel
• Move AP and YD levers to DISENGAGED position
• Operate pitch trim

Question 16

When will the Autopilot automatically disengage?

Answer 16

• Select GA mode.
• Fault detected in servo loop circuits.
• Loss of valid attitude reference.
• Loss of system power.
• Fault in engage circuits.
• Loss of yaw damper validity.

Question 17

When will the Autopilot fail to engage?

Answer 17

• AP DISC switch pressed.
• Any of the automatic disengage criteria.
• Failure to pass self-test sequence.
• Aircraft incorrectly configured.
• Flight Control Computer incorrectly configured.

Question 18

Which are the three diagnostic modes?

Answer 18

• report mode
• input test mode
• output test mode