Flight Controls

Question 1

What is the maximum rudder deflection…..

0° flaps?

5° flaps?

What system prevents this?

Answer 1

12°

18°

Rudder input restrict or mechanism. The flap lever is mechanically linked to the co-pilots forward quadrant.

*Aft rudder 2x deflection

Question 2

How are controls locked?

Answer 2

Ailerons: Mechanical control lock

Elevator and rudder: Hydraulic dampening

Question 3

How does flap auto trim work?

Answer 3

Between 15° and 35° both ways

Question 4

What happens if 1 pcu fails on the rudder?

Answer 4

Operating pressure on other PCU doubles

Question 5

When do outboard spoilers get disabled?

…re-armed?

What controls this?

Answer 5

Airspeed >170 kts

Airspeed thru 165k

FCECU

Question 6

What is the purpose of the Rudder Feel Trim and Summing Unit?

Where does it get inputs from?

Answer 6

Provides artificial feedback forces to the rudder pedals.

Receives input from rudder pedals and the yaw damper. It takes the two and transmits as a single input.

Question 7

How does hydraulic pressure to the rudder PCU vary with airspeed?

Answer 7

It decreases as airspeed increases. Rudder authority is limited as a function of airspeed by the FCECU which gets an input from the ADC. The reduced hydraulic pressure causes less rudder deflection.

Question 8

What is the indication of rudder trim indication failure?

Answer 8

An off scale deflection of the needle.

Question 9

Where does the yaw damper get it’s inputs from?

What if one fails?

Answer 9

2 FGMs. If one fails you lose the yaw damper.

Question 10

How do spoilers work on touchdown?

Answer 10

WOW and power leavers (PLA < 12°) send signal to FCECU and PSEU and the lift dump valves are energized.

Question 11

How is aileron trim activated?

Answer 11

Electrically. Done by deflecting both ailerons.

Question 12

What is the purpose of the tab on the ailerons

Answer 12

It’s a gear tab and assists in aileron movement.

Question 13

What is the purpose of the pitch feel and trim units (PFTU)

How many?

Answer 13

-Provide artificial feel (provided by the right pitch feel actuator.

2

Question 14

How many pitch feel actuators on each PFTU?

What happens if one fails?

Answer 14

2

FCECU detects failed pitch feel actuator and holds it at its last valid position. The other pitch feel actuator operates normally but with reduced artificial feel. T.he ELEVATOR FEEL caution light will come on.

Question 15

Where does the FCECU get it’s info from?

Answer 15

Both ADCs

Question 16

What controls elevator trim rate and how does it vary?

Answer 16

FCECU

Below 150 kts: High speed mode
Above 250 kts: Low speed mode.

Basically higher trim speed rates are required for lower airspeeds.

Question 17

What is the purpose of the Flap Control Unit (FCU)?

What is an advantage of having an FCU

If the FCU fails which caution lights come on?

Answer 17

Monitors and controls flap movements through the Flap Power Unit (FPU).

It minimizes non-selected flap movements,flap asymmetry if the flap drive line fails.

FLAP POWER or FLAP DRIVE caution lights.

Question 18

How does the Flap Power Unit drive the flaps?

Answer 18

Converts hydraulic power to rotary motion to operate the flap actuators.

Question 19

How are the flaps controlled and operated?

Answer 19

Electronically controlled and hydraulically operated.

Question 20

Which control column is connected to the spoilers?

….ailerons?

Answer 20

Capt: Spoilers

FO: Ailerons

Question 21

What happens if both rudder PUSH OFFs are pressed at the same time?

Answer 21

Nothing! Lights come on but PCUs don’t depressurize.

Question 22

How does the yaw damper work?

Answer 22

It’s an actuator that supplies automatic compensation for minor yaw acceleration. It requires an input from both FGMs and improves directional stability and turn co-ordination.

Question 23

What happens if you push either the SPLR 1 or SPLR 2 switchlight?

Answer 23

ROLL SPLR INBD HYD or ROLL SPLR OUTBD HYD (<165 kts) caution lights will illuminate. SPLR OUTBD caution light also comes on when you push SPLR 2 switch-light.

Question 24

What happens if you attempt to takeoff with the flight/taxi switch in taxi?

Answer 24

The switch will automatically spring to flight once the power leavers pas FI + 12 degrees. Spoilers will stay retracted and advisory lights will go out.

Question 25

How many static wicks on the bullet fairing, rudder, and each ailerons and elevators?

Answer 25

Bullet fairing 2

Ailerons 6

Elevators 4

Rudder 3

Ref: AOM 3.3 pg. 3-19 to 3-20