Flight Controls

Question 1

What is the difference between normal mode and direct mode?

Answer 1

There are no higher level functions available in direct mode

Question 2

What are the higher level functions associated with yaw?

Answer 2

Yaw damp
Turn coordination
Thrust asymmetry (not MESA)
Gain on airspeed- as airspeed increases, rudder deflection decreases

Question 3

What are the higher level functions associated with pitch?

Answer 3

Gain on airspeed
Elevator thrust compensation
AOA limiting

Question 4

What is the priority for the trim system?

Answer 4

Back-up
Captain
First Officer
Autopilot

Question 5

How is roll controlled?

Answer 5

Ailerons and multi-function spoilers (outer 3 spoilers on each wing)

Question 6

How man multi-function spoilers are on each wing? What are their functions?

Answer 6

5

3 outboard spoilers are used to assist in roll control and for ground spoilers

2 inboard spoilers are only used for ground spoilers

Question 7

When will the speed brakes automatically close even if the lever shows deployed?

Answer 7

Flaps > 2
Airspeed less than 180 kts
TLA > 70°

Question 8

What is the flap/slat extension/retraction sequence?

Answer 8

Slats extend first

Flaps retract first

Question 9

Will loss of airspeed data cause the flight controls to go into DIRECT mode?

Answer 9

Yes

Question 10

Can a FCM override pilot input?

Answer 10

No, the pilot always has supreme control

Question 11

What happens to artificial feel if flight controls are disconnected?

Answer 11

Artificial feel is felt at 1/2 the normal load

Question 12

How are the flight controls trimmed?

Answer 12

Roll & yaw: Ailerons and Rudder surfaces are repositions to a new “neutral position”

Pitch Horizontal Stabilizer

Question 13

Will the multi-function spoilers function in DIRECT mode?

Answer 13

Yes, for roll only and at a default fixed gain

Question 14

Will the speed brakes/ground spoilers function in DIRECT mode?

Answer 14

No

Question 15

What happens to the flight control system when the RAT is the only AC power source?

Answer 15

Horizontal stab trim operates at 1/2 speed
Slat/flap system operates at 1/2 speed
Slat/flap position is limited to 3 to allow adequate airspeed for the RAT

Question 16

What is the only primary flight control that is not FBW (fly-by-wire)?

Answer 16

Ailerons

Question 17

What are primary flight controls?

Answer 17

Ailerons
Multifunction spoilers
Elevator
Rudder

Question 18

What are secondary flight controls?

Answer 18

Horizontal stabilizer
Multifunction spoilers
Slats/flaps
Ground spoilers

Question 19

How long does the Electrical PBIT run for?

Answer 19

3 min

Do not turn on HYD pumps during
Do not disconnect AC power
Expires after 50 hrs since last successful PBIT (shows an EICAS caution message if on ground and it is expired)

Question 20

Explain the HYD PBIT?

Answer 20

1 min self test
Do not move flt controls
All HYD systems must be pressurized
Flt control actuators being tested
Flt control test status message displayed

Question 21

What is the FCM? What does it do?

Answer 21

Flight control module

In normal mode, provides control limits for different airspeeds.
Provides higher level functions: (some not all listed)
-airspeed augmentation
-elevator thrust compensation
-rudder flight authority
-yaw damper/turn coordination
etc.

Question 22

What is direct mode?

Answer 22

Takes FCM out of the loop and no higher level functions are provided.

Question 23

What is the ASCB?What does it do?

Answer 23

Avionics Standard Communication Bus

Data exchange between all FCMs

Question 24

What happens if there is a complete power failure in terms of the FBW flight control system?

Answer 24

There is a battery that will power the FBW system for 15 minutes.

Battery is charged by DC ESS BUS 3 during normal operation.

Has built in internal heater to insure it is above minimum temperature.

Question 25

When do the ground spoilers automatically deploy?

Answer 25

Weight on wheels
TLA below 26°
Wheel speed above 45 kts or airspeed above 60 kts

Question 26

When do ground spoilers automatically retract?

Answer 26

When wheel speed is below 45 kts for at least 5 seconds
OR
TLA 35° or more

Question 27

Higher level functions for the horizontal stabilizers?

Answer 27

Trim with autopilot on, speed brakes out, or to prevent structural damage.