Flight Controls

Question 0

How is roll control achieved?

Answer 0

2 ailerons
2 flaperons
14 spoilers (also for speedbrakes)

Question 1

Where do inputs from the pilot go?

Answer 1

4 ACE (actuator control electronics)
Then to the 3 PFC primary flight computers ( mixed with other data)
Then back to the ACEs and on to the control actuators. PCUs supply the force to move the flight controls.

Question 2

Envelope protection consists of what?

Answer 2

Warnings for :
Stall
Over speed
Bank angle

Question 3

What does the EEC thrust asymmetry function do?

Answer 3

Decrease power on the live engine to ensure yaw control is available. It is always available when flight controls are in normal mode.

Question 4

How many flight control modes are there?

Answer 4

3
Normal
Secondary
Direct

Question 5

What do you lose in secondary flight mode?

Answer 5

Autopilot
Stall, over speed, bank angle, gust suppression and thrust asymmetry
Manual control is fully available.

Question 6

What is direct flight mode?

Answer 6

There is no input from the primary flight computers. Pilot controls go straight from the ACEs to the actuators. Little difference in practice to secondary mode.

Question 7

How many high lift devices are there?

Answer 7

2 outboard flaps
2 inboard flaps
2 Krueger flaps
12 slats

Question 8

Which hydraulics move the elevators?

Answer 8

The centre moves both. The left moves the left, and the right moves the right.

Question 9

What moves the stabiliser?

Answer 9

2 electric actuators.

Question 10

In secondary and direct mode, does a control input for pitch move the stabiliser?

Answer 10

No, only the elevators.

Question 11

If armed, autothrottle will engage and provide a speed at the minimum manoeuvering speed. It will NOT engage when?

Answer 11

Pitch mode FLCH
Pitch mode TOGA
After take off below 400ftAGL
On approach below 100ftRA
During descent in VNAV SPD

Question 12

What is the difference in control ‘feel’ logic between normal and secondary/direct modes?

Answer 12

Normal uses speed - high speed high force

Secondary and direct use flap position. Flaps up high, flaps out decreased force.

Question 13

Does the alternate trim signal through a computer?

Answer 13

No, wires go directly from the switch to the stabiliser to control pitch.

Question 14

When do you see the stab trim on EICAS?

Answer 14

When on the ground, and after take off 10 seconds after gear up, or 60 seconds after lift off.
Various non normals, with Stab, flight computers, modes etc
After landing and trim is used, or ground speed less than 40kts

Question 15

Wheel to rudder cross tie function works in what flight mode?

Answer 15

Secondary and direct.

Question 16

Where are the trim weight sensors?

Answer 16

Nosewheel

Question 17

Are all the spoilers hydraulically activated?

Answer 17

No. Pairs 4 and 11, and 5 and 10 are electrical actuators.

Question 18

When will speedbrakes automatically deploy?

Answer 18

Thrust levers closed after 85 Kts on take off
Landing with speedbrakes armed
Reverse thrust selected on landing even if not in armed

Question 19

How many slats are there?

Answer 19

6

5 outboard 1 inboard of the engine.

Question 20

What are the operating modes for the the flaps and slats?

Answer 20

Primary - flap lever, hydraulic
Secondary- flaps lever, hydraulic or electric
Alternate - alternate flap selector, electric

Question 21

Do flaps move for ‘Flap 1’ selection?

Answer 21

No, only the leading edge slats go to mid range, aloe with the Krueger flaps.

Question 22

When do the slats go beyond mid range?

Answer 22

25 and 30 selection

Question 23

When does the autogap function work?

Answer 23

With a high angle of attack, and speed below 225 Kts.

Question 24

Does the pilot have control over cruise flaps?

Answer 24

No, and no indications.

Question 25

Does the secondary mode use the slat pre gap function?

Answer 25

Yes, below 225kts and flap lever out of up.