Flight Controls Flashcards
Draw the Flight Control System (Elevator, Ailerons, Stabilizer, Rudder, Slats/Flaps)
see study guide
What are the primary flight controls?
Ailerons, multifunction spoilers, elevator, rudder
What are the secondary flight controls?
Horizontal stab, multifunction spoilers when used as ground spoilers, slats/flaps, ground spoilers
The flight controls are moved via
Fly-by-wire FBW and conventional cables (aileron only)
How does the FBW system’s higher level functions work?
The FBW system incorporates higher level functions for safety and to reduce pilot workload. They get their commands from the FCM Flight Control Module. When higher level functions are not working, the controls are operating in Direct Mode.
Which controls have higher level functions? Which do not?
Elevator, multifunction spoilers, rudder, horizontal stab (not flaps, slats, ground spoilers, or ailerons)
What controls pitch?
Elevator, horizontal stab
Describe how the elevator works, draw the picture from the study guide
electrically controlled, hydraulically actuated; PCU Power Control Unit (a hydraulic actuator that replaces conventional control cables), ACE Actuator Control Electronic (the electronic unit controlling the PCU), and the FCM Flight Control Module (a computer inputting higher level functions)
What are the elevator higher level functions?
Gain on Airspeed (as airspeed increases, pitch deflection decreases), Elevator thrust compensation (pitch control is maintained during thrust changes), AOA limiting (essentially does not allow the aircraft to stall)
Describe how the horizontal stabilizer works, draw the picture from the study guide
electrically controlled, ELECTRICALLY actuated; HSA Horizontal Stabilizer Actuator (the electric motor that moves the horizontal stabilizer), ACE Actuator Control Electronic (the electronic unit controlling the HSA), FCM Flight Control Module (a computer interface for higher level functions
What are the higher level functions for the horizontal stab?
Configuration change compensation: Keeps the airplane trimmed via the autopilot and deployment of the speed brakes, prevents structural damage at high speeds
What is the trim priority?
Backup, captains, first officers, autopilot
What controls roll?
Ailerons and multifunction spoilers
Describe how the ailerons works, draw the picture from the study guide
mechanically controlled (No fly-by-wire), hydraulically actuated, PTU Power Control Unit (a hydraulic actuator controlled by conventional cables)
What high level functions are applied to the ailerons?
The aileron has no high-level functions
Describe how the multifunction spoilers work
5 panels per wing, the 3 outer panels are multifunction spoilers which (assist roll, are speed brakes, are ground spoilers), there are also 2 inner panels which are only used as ground spoilers
How is roll assist accomplished?
The 3 multifunction spoilers (3 outer panels) assist roll - in normal mode they are scheduled as a function of airspeed and flap setting - in direct mode, fixed gain applied independent of airspeed and flap setting
What are the speed brakes? How do they work?
The 3 outer panels (multifunction spoilers), when the handle is in the open position, the speed brakes will auto close if: slat/flap selection is 2 or greater, airspeed is less than 180kts, or TLA is greater than 70 degrees. SPEED BRAKES WILL NOT WORK IN DIRECT MODE
How do the ground spoilers work?
All panels are ground spoilers, operational on the ground only, deploys via WOW, Wheel speed above 60kts, TLA below 26deg and retract via Wheel Speed, TLA GROUND SPOILERS WILL NOT WORK IN DIRECT MODE
Describe how the rudder works, draw the picture from the study guide
electrically controlled, hydraulically actuated, PTU Power Control Unit, ACE Actuator Control Electronic, FCM Flight Control Module
What are the higher level functions for yaw?
yaw damp, turn coordination, gain on airspeed (as airspeed increases, rudder deflection decreases)
Describe how the flaps and slats works, draw the picture from the study guide
electrically controlled, electrically activated, PDU POWER DRIVER UNIT (the electric actuators that moves the flaps/slats on their track, ACE
How many slats are there?
8, 4 on each wing with 2 positions -15deg for flaps 1-3 and 25deg for flaps 4-full
What kinds of flaps do we have?
4 double-slotted/fowler-type flaps (2 per wing), 7 positions
What extends first, what retracts first?
Slats extend first, flaps retract first
What happens if the flaps are asymmetrical?
A skew sensor protects the flaps from an asymmetric position
What is the only primary flight control that is not FBW?
Ailerons
What is the difference between normal and direct mode?
There are no higher-level functions available in direct mode
What are the higher-level functions associated with pitch?
Gain on airspeed, elevator thrust compensation, AOA limiting
What are the higher level functions associated with yaw?
Yaw damp, turn coordination, gain on airspeed - as airspeed increases, rudder deflection decreases
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 many spoilers are on each wing? What are their functions?
5, 3 outboard multifunction spoilers are used to assist in roll control, as speed brakes, and as ground spoilers; 2 inboard spoilers are only used as ground spoilers
When will the speed brakes automatically close even if the lever shows deployed?
Slat/Flaps selected to 2 or greater, airspeed less than 180kts, TLA greater than 70 degrees
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 the flight controls are disconnected?
Artificial feel is felt at 1/2 the normal load on the CA side