Flight Controls System Ch. 9

Question 1

What does the flight control system consist of?

Answer 1

Primary flight controls, secondary flight controls, multifunction spoilers (MFS), elevator & rudder

Question 2

What controls are hydraulically actuated?

Answer 2

The MFS, elevator and rudder

Question 3

What are the secondary flight controls? How are they actuated?

Answer 3

Flaps, speed brakes, ground spoilers

Hydraulically

Question 4

Which of the primary flight controls are fly by wire?

Answer 4

The multifunction spoilers, and the rudder

Question 5

Which aileron has a trim tab?

Answer 5

Left

Question 6

Are any of the secondary flight controls fly by wire?

Answer 6

Yes, the spoilers

Question 7

What does the stall protection system consist of?

Answer 7

Stick shaker
Stick pusher
AOA Indications
Aural warnings
Autopilot disconnect
Auto ignition

Question 8

What is the stick pusher function provided by?

Answer 8

Autopilot pitch servo

Question 9

What is the purpose of the FCECU?

Answer 9

Command/monitor flight controls

Question 10

How many FCECU’s are there?

Answer 10

2

Question 11

What is the MCU?

Answer 11

Motor Control Unit
Two channel motor the interfaces with the FCECU through dedicated wiring - one channel controls HSTA (Horizontal Stabilizer Trim Actuator) motor A and the other to motor B

Question 12

How many channels do the FCECU’s have? What are they?

Answer 12

Two - Normal & emergency

Question 13

How many multifunction spoilers are there?

Answer 13

4

Question 14

How are the multifunction spoiler actuators operated?

Answer 14

Electrically operated hydraulic servo actuators

Question 15

What kind of valve does the MFSA incorporate?

Answer 15

An integral hold down check valve

Question 16

How many functions does the integral hold down check valve have? What are they?

Answer 16

3: Normal, Checked, and Relief

Question 17

In the normal mode, how does the integral hold down check valve operate?

Answer 17

Sufficient hydraulic pressure allows the valve to free float, providing fluid to extend or retract side of the actuator as required

Question 18

In the checked mode, how does the integral hold down check valve operate?

Answer 18

When the system senses insufficient pressure from the hydraulic system the valve will prevent actuator operation which prevents spoiler float

Question 19

In the relief mode, how does the integral hold down check valve operate?

Answer 19

If system pressure exceeds 3,600 psi, an over pressure relief is built in to release pressure to prevent damage in the case of thermal expansion

Question 20

How are each sides of the elevator connected to each other?

Answer 20

Through the force disconnect unit

Question 21

What provides elevator position to the synoptic pages on the DU?

Answer 21

FCECU

Question 22

If hydraulic pressure is lost, how can the elevators be controlled?

Answer 22

Manual reversion

Question 23

What is the purpose of the eddy current damper?

Answer 23

Dampen the high rate of force applied to un-jam the control loop developed due to the abrupt release of the force disconnect unit

Question 24

What is the Q-Feel Actuator?

Answer 24

Provides increased column feel forces at higher airspeeds by changing the length of the feel spring in line with the control column to the elevator actuator linkage

Question 25

What is the Q Feel controlled by?

Answer 25

Electrically by FCECU 2, hydraulically by the right hydraulic system

Question 26

What does the force disconnect unit do?

Answer 26

Allows for independent control of each elevator surface

When disconnected, commands from pilots side will command Left elevator. Commands from copilots side will command right elevator.

Question 27

What is lost if the right elevator control loop is jammed?

Answer 27

Stick pusher, Q Feel, Autopilot

Question 28

What are the type of flaps?

Answer 28

Fowler flaps

Question 29

When would the FCECU stop flap motion?

Answer 29

Flap asymmetry of 3 degrees

Question 30

How long does it take flaps to go from 0 - 39 degrees?

Answer 30

27 seconds

Question 31

What does the alternate flap switch do?

Answer 31

Engages the alternate mode that provides a secondary method for controlling the flaps and the event of a flat lever RVDT failure, a failure in the normal channel command path, or a failure in the normal channel monitor path

Question 32

How many panels do the spoilers have?

Answer 32

6 (3 per wing)

Question 33

What do the innermost spoiler panels on the wings function as? What do the remaining two function as?

Answer 33

Ground spoiler only

Multifunction spoiler

Question 34

What commands the roll assist function of the multi function spoiler?

Answer 34

The FCECU 2

Question 35

What is available to provide an alternate means of roll control when a there is an aileron jam?

Answer 35

The aileron disconnect handle on the yoke

Question 36

How does the (ADU) aileron disconnect unit operate?

Answer 36

Disengage is the pilot yoke from the mechanical linkage, once it is able to turn freely, the rotation will continue to cause the RVDTs on the pilots wheel to generate roll commands

Question 37

What are the two levels of stall protection?

Answer 37

Stick shaker and stick pusher

Question 38

How does the stall protection system work?

Answer 38

1st phase - SPS commands auto pilot and auto throttles to disengage, initiate auto ignition, and activates the stick shakers

If no corrective action is taken and the angle of attack increases to critical AOA, the 2nd phase is activated - Stick Pusher.

Stick pusher can be turned off by selecting the stick pusher button on the center pedestal to OFF, or the AFCS DISCON bar to OFF