Flight Control Flashcards
Recall the modes of rudder operation
There are two modes of rudder operation – powered and manual
Normally, the rudder is powered by the right hydraulic system
If right system hydraulic pressure is too low, or manual mode is selected (by
pushing the HYD CONT RUDDER switch to the OFF position), the rudder control
tab unlocks
In manual mode, the rudder pedals move the control tab on the rudder and
aerodynamic forces on the control tab move the rudder
Recall features of the aircraft rudder limiting systems
The aircraft’s primary rudder limiter protects the empennage from excessive loads by
restricting rudder travel as airspeed increases. It is a mechanical system operated by
ram air pressure from a pitot tube on the leading edge of the vertical stabilizer.
A second rudder restricting system provides rudder limiting in the event the primary
system fails. The system has two positions, restricted and unrestricted, controlled by
the Flight Control Computer (FCC), as a function of airspeed.
Recall SPEED BRAKES will retract as throttles are advanced to a high thrust position
If the throttles are advanced to high thrust while the speed brakes are extended,
the speed brake handle remains in position, but the speed brakes automatically
retract – confirmation can be seen on the CONFIGURATION SD
Recall how optimum flap settings are selected for takeoff or landing performance
FLAP/SLAT Control Handle UP/RET - Retracts flaps and slats EXT - Flap range (0, 13, 18, 25, 40 degrees FLAP T.O. SEL Thumbwheel Rotate - Sets an adjustable detent which works in conjunction with the FLAP/SLAT control handle in setting flap position for optimum takeoff or landing performance FLAP T.O. SEL Position Indicator Window Responds to movement of FLAP T.O. SEL thumbwheel to indicate the selected flap setting
Recall how the flap and slat position is displayed
1. On the CONFIGURATION SD synoptic, flaps position is displayed under each wing with an individual digital readout of flaps setting. SLAT EXT is displayed below the fuselage when slats are extended 2. The flap/slat position indication is also displayed on the PFDs. The SLATS indication is removed once the FLAPS are extended When the flaps/slats are in transit, the selected FLAP/SLAT handle position is displayed on the PFDs with up or down arrows indicating the direction of flap/slat movement
Recall how the slats are positioned
Five individual slat sections on each wing operate as a single unit
The slats are controlled with the FLAP/SLAT handle; there are two
slat positions - UP/RET and EXT (0 or greater flaps)
Slats are normally powered by both hydraulic systems; however,
either hydraulic system can fully operate the slats
Recall how stabilizer trim is displayed (2)
The stabilizer position is displayed at the top of the CONFIGURATION SD synoptic, above the airplane symbol Stabilizer position is also displayed at the top of the SECONDARY ENGINE SD synoptic
Recall the difference between the primary and alternate stabilizer trim systems
Horizontal stabilizer trim is controlled by the primary
trim switches, the alternate trim switches, or the
autopilot
The primary trim switches are on the control wheel
and used for manual stabilizer trimming at a faster rate
The alternate trim switches
(ALT LONG TRIM) are on
the pedestal and are used
for manual stabilizer
trimming at a reduced rate
NOTE: The autopilot trims
the airplane using the
alternate trim system
Recall how the stabilizer is trimmed using the primary trim switches
• When both primary trim switches on either control wheel are moved simultaneously,
the primary trim brake is released and the primary trim motor drives the stabilizer in the
commanded direction
• Separate movement of either switch does not produce stabilizer movement
Recall the meaning of the stabilizer movement warning horn
• A warning horn sounds to alert the crew any time the stabilizer moves more than one
degree, and continues to sound once for each approximately one degree of stabilizer
movement
• The “stabilizer motion” voice warning also sounds
• The “stabilizer motion” voice warning and the warning horn are inhibited on the ground
Explain the function of the STABILIZER TRIM Brake Switch
The STABILIZER TRIM switch is a guarded switch and has two positions: OFF and Normal
• Normal - OFF light is extinguished and primary stabilizer trim is enabled
• OFF – (switch is pushed) amber OFF illuminates and electrical power to the brake
is removed, setting the brake to prevent stabilizer movement
Recall how the elevators are normally positioned for pitch control
• The elevators are aerodynamically positioned by control tabs, which are
mechanically connected to the control columns
• A variable load feel mechanism simulates aerodynamic forces and returns the
control columns to an artificial center position when they are released
Recall each elevator has two tabs
• Control Tabs: Operated by the control columns, which then aerodynamically
position the elevators
• Geared Tabs: As each elevator is moved, geared tabs are deflected, providing
aerodynamic assistance in moving the elevators
• A total of four tabs aerodynamically position the elevators (two each side)
Recall how pitch control is maintained if either control column jams
• An override mechanism, installed on the torque tube connecting the two control
columns, allows each column to operate independently, in the pitch axis, should
either side jam
• A substantial amount of force, about 130 pounds, must be applied to the operable,
of free column, for the mechanical disconnect to occur
• Once disconnected, maintenance is required
Recall the function of the elevator augmentation system
• The elevator has two hydraulic boost cylinders that augment elevator control during
a deep stall recovery, providing additional nose down capability
• The system is powered by the left hydraulic system with an accumulator backup in
the event system pressure is lost.
• When the elevator augmentation system is activated by pushing the control
columns full forward, the elevators move to full deflection, trailing edge down
