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Flashcards in Flight Controls Deck (65)
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0

In the event of a loss of all hydraulic power, what flight controls are available?

Two electrically actuated spoiler pairs and the electrically actuated stabilizer.

1

In the event of a complete loss of flight control signaling, loss of all input to the FCC, What flight controls are available?

One spoiler pair and the stabilizer

2

When is primary pitch trim inhibited?

When the autopilot is engaged.

3

Which has priority over the other, Primary or Alternate pitch trim?

Alternate trim switches have priority.

4

Moving the pitch trim on the ground (primary or alternate) moves which control surface?

On the ground, moving pitch trim switches will directly position the stabilizer.

5

What happens when you move the primary pitch trim switches in the air, in normal mode?

The trim reference speed is changed.

7

Identify the power sources for the horizontal stabilizer.

Electric control units powered by L2 and R2 AC buses.

8

In which flight control mode(s) is Flight Envelope Protection available?

Only in normal mode.

9

What will cause the flight control system to revert to the secondary mode?

Inertial or air data is insufficient to support normal mode, or
ALL slat & flap position data is unavailable.

10

Can the pilot select secondary flight control mode manually?

No

11

Are the ACE's fully functional in secondary mode?

Yes. ACE's continue to receive and process pilot inputs.

12

What functions are not available in secondary flight control mode?

-Autopilot
-Auto Speedbrakes
-Envelope protection
-Gust suppression
-Pitch compensation
-Roll/Yaw asymmetry compensation
-Tail strike protection

13

How can the flight control mode be selected to direct mode?

By manually moving the PRIMARY FLIGHT COMPUTERS switch to DISC.

14

What flight control functions no longer work when direct mode is manually selected?

Same as for secondary mode.
-Autopilot
-Auto Speedbrakes
-Envelope protection
-Gust suppression
-Pitch compensation
-Roll/Yaw asymmetry compensation
-Tail strike protection

15

In normal mode when the pitch trim is moved, what flight control surface is actually moved?

The elevators.
The PFC's automatically move the elevators to achieve the trim change, then move the stabilizer to streamline the elevator.

16

If the stabilizer is manually shut down or failed, what does movement of the pitch trim cause?

In the normal mode, pitch trim commands still change the trim reference speed and the elevators move to trim the airplane.

17

How and where is stabilizer position indicated to the crew?

Indicated on the EICAS and the flight control synoptic display.

18

When does the EICAS stabilizer trim position indication disappear?

Indication blanks when:
-Gear up for 10 seconds, or
-60 seconds after liftoff

19

When does the EICAS stabilizer trim position indication automatically appear?

-On the ground at power-up
-After landing and any pair of trim switches are used
-After landing and groundspeed is less than 40kts
-In the air, any of the following EICAS messages are active:
"FLIGHT CONTROL MODE"
"PRI FLIGHT COMPUTERS"
"STABILIZER"
"STABILIZER SHUTDOWN"
"PITCH UP AUTHORITY"
"PITCH DOWN AUTHORITY"

20

What causes the EICAS "STAB GREENBAND" message to display?

-Computed green band disagrees with pressure transducer data.
-The 2 transducer values are not within the set tolerance
-Either transducer has failed

21

What does the stabilizer green band compare for the correct stab trim?

It compares FMC calculated stabilizer greenband to the validation limits from the transducers.

22

What is the default range for the stab green band?

From 4 to 9 units.

23

How does the stall protection system operate?

It limits the speed to which the airplane can be trimmed. Pilot must apply aft column pressure at twice the normal force to maintain airspeed below the minimum maneuvering speed.

24

In flight in normal mode, what does movement of the rudder pedals command?

Rudder input commands a sideslip maneuver with the angle dependent upon the size of the pedal input.

25

On the ground above 60kts, how does the flight control system attempt to maintain a yaw rate near zero?

By commanding rudder to counter the majority of the yawing moment.

26

In flight, how does the flight control system attempt to maintain a zero roll rate and sideslip?

System commands rudder and lateral inputs to counter the moments.

27

After an initial input, how does the system off load any steady state inputs?

After initial input, the system off loads any steady state lateral inputs to the rudder.

28

What is the Wheel to Rudder cross-tie, and when is it available?

A function reducing the maximum sideslip and vertical fin loads.
Available in secondary and direct modes.

29

How many rudder trim rates are available?

2. High and low rate.

30

When are any manual rudder trim inputs automatically zeroed?

During takeoff roll at 30kts and on landing