Flight Controls Flashcards
What is the difference between normal mode and direct mode?
There are no higher level functions available in direct mode
What are the higher level functions associated with yaw?
Yaw damp
Turn coordination
Thrust asymmetry (not MESA)
Gain on airspeed- as airspeed increases, rudder deflection decreases
What are the higher level functions associated with pitch?
Gain on airspeed
Elevator thrust compensation
AOA limiting
What is the priority for the trim system?
Back-up
Captain
First Officer
Autopilot
How is roll controlled?
Ailerons and multi-function spoilers (outer 3 spoilers on each wing)
How man multi-function spoilers are on each wing? What are their functions?
5
3 outboard spoilers are used to assist in roll control and for ground spoilers
2 inboard spoilers are only used for ground spoilers
When will the speed brakes automatically close even if the lever shows deployed?
Flaps > 2
Airspeed less than 180 kts
TLA > 70°
What is the flap/slat extension/retraction sequence?
Slats extend first
Flaps retract first
Will loss of airspeed data cause the flight controls to go into DIRECT mode?
Yes
Can a FCM override pilot input?
No, the pilot always has supreme control
What happens to artificial feel if flight controls are disconnected?
Artificial feel is felt at 1/2 the normal load
How are the flight controls trimmed?
Roll & yaw: Ailerons and Rudder surfaces are repositions to a new “neutral position”
Pitch Horizontal Stabilizer
Will the multi-function spoilers function in DIRECT mode?
Yes, for roll only and at a default fixed gain
Will the speed brakes/ground spoilers function in DIRECT mode?
No
What happens to the flight control system when the RAT is the only AC power source?
Horizontal stab trim operates at 1/2 speed
Slat/flap system operates at 1/2 speed
Slat/flap position is limited to 3 to allow adequate airspeed for the RAT
What is the only primary flight control that is not FBW (fly-by-wire)?
Ailerons
What are primary flight controls?
Ailerons
Multifunction spoilers
Elevator
Rudder
What are secondary flight controls?
Horizontal stabilizer
Multifunction spoilers
Slats/flaps
Ground spoilers
How long does the Electrical PBIT run for?
3 min
Do not turn on HYD pumps during
Do not disconnect AC power
Expires after 50 hrs since last successful PBIT (shows an EICAS caution message if on ground and it is expired)
Explain the HYD PBIT?
1 min self test Do not move flt controls All HYD systems must be pressurized Flt control actuators being tested Flt control test status message displayed
What is the FCM? What does it do?
Flight control module
In normal mode, provides control limits for different airspeeds.
Provides higher level functions: (some not all listed)
-airspeed augmentation
-elevator thrust compensation
-rudder flight authority
-yaw damper/turn coordination
etc.
What is direct mode?
Takes FCM out of the loop and no higher level functions are provided.
What is the ASCB?What does it do?
Avionics Standard Communication Bus
Data exchange between all FCMs
What happens if there is a complete power failure in terms of the FBW flight control system?
There is a battery that will power the FBW system for 15 minutes.
Battery is charged by DC ESS BUS 3 during normal operation.
Has built in internal heater to insure it is above minimum temperature.
When do the ground spoilers automatically deploy?
Weight on wheels
TLA below 26°
Wheel speed above 45 kts or airspeed above 60 kts
When do ground spoilers automatically retract?
When wheel speed is below 45 kts for at least 5 seconds
OR
TLA 35° or more
Higher level functions for the horizontal stabilizers?
Trim with autopilot on, speed brakes out, or to prevent structural damage.
