Automatic Flight Control and Augmentation System (AFCAS)

Question 1

How many flight control computers are there on the aircraft?

Answer 1

Either two or three, depending on configuration.

Question 2

How many flight augmentation computers?

Answer 2

1

Question 3

Which FCC serves which side?

Answer 3

FCC 1 serves the left side, FCC 2 serves the right side. FCC 3, if available, acts as a backup.

Question 4

What is the effect of an FCC failure?

Answer 4

• onside autopilot disconnects
• On side FD bars disappear
• Fault light on onside FD Source P/B
• Level 1 alert

Steering guidance from off-side FD source can be obtained by pushing the Source P/B. Engaging the of-side AP remains possible.

Question 5

How many IRS’s are required for autopilot engagement?

Answer 5

At least two IRS’s are required for auto-flight. They must be in NAV or ATT modes.

Question 6

How can you disengage the AP?

Answer 6

• push disconnect button on the control yoke (preferred)
• Pull down the disconnect bar on the FMP
• pressing both stab trim switches for > 2.5 sec
• Automatically in case of a failure

Question 7

Using the heading knob, how can you obtain a new heading?

Answer 7

• HDG HOLD - push the heading knob to maintain current heading.
• HDG SELECT - - rotate knob to desired heading and pull knob to obtain a new heading.

Question 8

How do you activate V/S mode?

Answer 8

rotate pitch wheel or by selecting AP on while not in TO mode.

Question 9

How can you activate LVLCH?

Answer 9

target altitude on the FMP then push LVLCH P/B or pull the ALT knob (not in PROF).

Question 10

In ALT HOLD mode, how do you achieve a new altitude?

Answer 10

ALT HOLD mode - push ALT knob to level off slightly below/above the altitude at which push occured.

Rotate ALT knob to desired altitude then use LVLCH or PROF to climb or descend to the new altitude.

Question 11

What is the difference in aircraft reaction between V/S and LVLCH?

Answer 11

Reaction to LVLCH is slow to ensure passenger comfort. V/S ensures a faster aircraft response.

Question 12

What does pushing the ALT knob achieve?

Answer 12

Push ALT knob to engage ALT HOLD. Aircraft will level off slightly below/above the altitude at which push occured.

Question 13

In V/L mode, when does VOR capture occur?

Answer 13

at approximately 1/2 a dot

Question 14

In APP mode (LAND), when does localizer capture occur?

Answer 14

approx 2 dots

Question 15

How can you set up an FMS NAV capture?

Answer 15

1. Set up an intercept heading using HDG SELECT
2. Once on the intercept path select NAV

Question 16

When cruising in PROF mode what must you do to initiate descent?

Answer 16

• set target altitude on the FMP
• Arm descent by pulling the ALT knob.

Question 17

In LAND mode, what is the significance of LAND 2 or LAND 3?

Answer 17

These modes indicate the aircraft’s autoland capability.

LAND 2 indicates two FCC’s are engaged and controlling the aircraft (Fail-Passive Automatic automatic flight control. system which, upon occurrence of any single failure, should not cause significant displacement of the aircraft from its approach path or altitude loss below the nominal glidepath. A manual landing or go around can then be made. Suitable for CAT II approach and auto land).

LAND 3 indicates there are three FCC’s engaged and controlling the aircraft. (fail-operational system where in the event of a failure, the approach, flare and landing can be completed by the remaining part of the automatic system. Suitable for CAT III approach)

Question 18

How do you arm LAND mode?

Answer 18

• Select ILS frequency at the ILS panel.
• Select APP on the APP/VOR P/B on the EFIS panel
• Use HDG SELECT or NAV top establish an intercept on the localizer.
• When with 15 degrees of the LOC, push the LAND P/B at the FMP.

Question 19

What limit is there on LOC and G/S capture?

Answer 19

• LOC intercept not greater than 90 degrees
• G/S capture will not occur before LOC capture and not below 1000 ft AGL.

Question 20

How do you selct GA mode? What should happen?

Answer 20

• Pull both TOGA trigger for at least 1 second
• ATS will advance thrust levers to TOGA
• Airspeed limit 200 kts
• V/S limit 2000 fpm (1000 fpm OEI)

Question 21

On take-off, how do you engage TOGA? How should the aircraft be aligned?

Answer 21

• Pull both TOGA trigger for at least 1 second
• aircraft must be aligned with RWY centerline

Question 22

What pitch angles will be displayed during takeoff?

Answer 22

• Before TOGA triggers are pulled 0 deg.
• When TOGA triggers are pulled 10 deg.
• After rotation - V2 + 10 kts limited to 18 deg.

Question 23

How many autothrottle (ATS) channels are there and what do they drive?

Answer 23

• 2 separate auto-throttle channels drive each associated thrust levers

Question 24

What happens if one channel fails?

Answer 24

Thrust levers are tied by a clutch and move together.

Question 25

How is ATS engaged? Disengaged?

Answer 25

• Armed on the ground by pressing the ATS P/B on the FMP
• Engaged by pulling the TOGA triggers for at least 1 second
• Normally disengaged by pressing the disengage buttons on the sides of the thrust lever handles.

Question 26

Can you override the ATS?

Answer 26

The ATS can be overridden at anytime.

Question 27

Why does the ATS declutch at 80 knots? How do you know this has occurred?

Answer 27

The ATS de-clutches at 80 knots to prevent inadvertent thrust lever retardation during take-off due to a fault.

ATS declutch is indicated by two white D’s adjacent to the EPR speed tape at the EPR TO position.

Question 28

What precautions should you take with the ATS if taking off into a strong headwind?

Answer 28

Advance thrust levers to 1.3 EPR before pulling the TOGA triggers to ensure TO EPR is reached before 80 knots (declutch speed)

Question 29

How is the stabilizer trimmed a) automatically, b) manually, and c) if both FAC channels fail?

Answer 29

a. automatically when AP selected in response to AP commands.
b. Manually using the STAB TRIM switches on the control yoke.
c. Using the STAB TRIM WHEEL if both FAC’s fail

Question 30

What is the effect of operating only 1 half of the stab trim switch?

Answer 30

Moving only 1/2 of the stab trim switch momentarily will have no effect. If 1/2 of the stab trim switch is held for > 15 seconds the stab trim is disconnected + Alert + non resettable fault.

Question 31

What happens if the pilots operate the stab trim switches in opposite directions?

Answer 31

Trim does not move