Flight Controls - Question Bank Flashcards
Describe the function of the Stabilizer (STAB) Trim Cutout Switches, AUTO position.
- Supplies hydraulic power for stabilizer trim
- Shuts off related system hydraulic power if unscheduled trim detected.
What surface component is moved when stabilizer trim inputs are made?
- Leading edge of the movable horizontal stabilizer
- Stabilizer trim varies the angle of incidence of the horizontal stabilizer.
State what occurs when the Stabilizer Trim CUTOUT switches are in CUTOUT.
Shuts off related hydraulic power to stabilizer trim.
Describe the function of the alternate trim switches.
- Trim commands through a separate control channel
- Increased range of stabilizer trim travel
How do the FMCs calculate correct stabilizer trim greenband?
They use:
- Calculated CG
- calculated gross weight
- Takeoff thrust de-rate selection
How does the aircraft provide a crosscheck to ensure the correct greenband has been displayed?
Nose gear oleo pressure switch position is compared to the calculated greenband
What is the effect on stabilizer trim if the control wheel stabilizer trim switches are used while the autopilot is engaged?
- Single autopilot engaged: the autopilot will disengage and the stabilizer trim will move in the desired direction
- Multiple autopilots engaged: the control wheel stabilizer trim switches are inhibited
State the effect on the autopilots and stabilizer trim, if the alternate trim switches are used with any number of autopilots engaged.
Alternate trim switches:
- override autopilot trim commands
- do not cause autopilot disengagement
How many spoiler panels are provided?
6 panels on each upper wing
Which spoiler panel does not function as a flight spoiler?
Inboard spoiler on each wing
Which spoiler panels function as speedbrakes in flight?
4 inboard spoilers on each wing
Which spoiler panels function as ground spoilers when on the ground?
All 6 spoilers on each wing
Which spoiler panel is displayed on the EICAS status display?
- 4th panel from the left wingtip on the left wing (flight spoiler, speedbrake, and gnd spoiler)
- R outermost panel (flight and gnd spoiler only - speedbrake extension is not displayed on the right wing spoiler indicator)
Which spoiler panels are extended with the speedbrake lever in the flight detent position?
- 2 inboard spoilers on each wing extended to mid-travel
- 2 mid-span spoiler panels on each wing extend to full travel
When do spoiler panels extend to the UP position during landing, if the speedbrake lever is ARMED?
- Main landing gear touchdown
- Thrust levers 1 AND 3 near idel
When do the spoiler panels extend to the UP position during landing if the speedbrake lever is NOT Armed?
- Main landing gear touch down
- Thrust levers 1 AND 3 near idle
- Reverse thrust levers 2 OR 4 pulled up to the idle detent
Since the speedbrake lever is in the DN position during takeoff, what action provides an automatic spoiler function for RTO?
Reverse thrust levers 2 OR 4 pulled to idle
For go-around protection, what action drives the speedbrake lever to the DN position?
Thrust lever 1 OR 3 advanced from idle (regardless of whether ground spoilers were automatically or manually selected)
Which elevator panels are displayed on the Surface Position Indicator?
Left and right outboard elevator positions
What can you do if you lose elevator control due to a jam?
When significant manual force is applied to the control column, shear outs between the inboard and outboard elevators allow elevator control to be regained
Describe the elevator feel system.
- Mechanism provides artificial feel at control columns
- Force increases as airspeed increases
- If both Hyd Sys 2 & 3 fail- mechanical springs provide feel force (feel force is not longer a function of airspeed).
How does the aileron lockout system work?
What is its purpose?
Works: Locks the outboard ailerons in the neutral position at 238 knots
Purpose:
- Permits full travel of the outboard ailerons at low airspeeds
- Prevents over-controlling at high airspeeds
- Provides the required roll authority at low airspeeds
What would happen if you use aileron trim with the autopilot engaged?
- Aileron neutral point is repositioned
- When A/P disengaged- the wheel and ailerons move to the repositioned aileron neutral point
- Airplane responds with roll proportional to the amount of aileron trim input
How do the rudder ratio changers work?
- Gradually reduce each rudder surface’s response to pedal inputs as airspeed increases
- Protects vertical tail from stresses caused by large rudder surface deflections at high airspeeds
What is the purpose of the yaw dampers?
- Improve airplane directional stability
- Provide turn coordination
