Flight Controls Flashcards
FLIGHT CONTROL (Switches)
STBY RUD: Activates standby hydraulic system pump and opens standby rudder shutoff valve to pressurize standby rudder power control unit
OFF: Closes flight control shutoff valve isolating ailerons, elevators and rudder from associated hydraulic system pressure
On (guarded position) - normal operating position
Flight Control LOW PRESSURE (lights)
Illuminated:
- indicates low hydraulic system (A or B) pressure to ailerons, elevator, and rudder
- deactivated when associated FLIGHT CONTROL switch is positioned to STBY RUD and standby rudder shutoff valve opens
Flight SPOILER switches
ON (guarded position): Normal operating position
OFF - closes the respective flight spoiler shutoff valve
Note: Used for maintenance purposes only
YAW DAMPER (switch)
OFF - disengages yaw damper
ON:
- engages main yaw damper to main rudder power control unit if the B FLT CONTROL switches are in the STBY RUD position
STANDBY HYD lights
Standby Hydraulic Low Quantity Light (Amber)
- indicates low quantity in standby hydraulic reservoir
- always armed
Standby Hydraulic Low Pressure Light (amber)
- indicates output pressure of standby pump is low
- armed only when standby pump operation has been selected or automatic standby function is activated
STBY RUD ON light (amber)
- indicates the standby rudder system is commanded on to pressurize the standby rudder power control unit
ALTERNATE FLAPS (master switch)
OFF - normal operating position
ARM - closes TE flap bypass valve, activates standby pump, and arms the ALTERNATE FLAPS position switch
ALTERNATE FLAPS (position switch)
Functions only when the ALTERNATE FLAPS master switch is in ARM.
UP:
- electrically retracts TE flaps
- LE devices remain extended and cannot be retracted by the alternate
OFF: normal operating position
DOWN (spring loaded to OFF):
- (momentary) fully extends LE devices using standby hydraulic pressure
- (hold) electrically extends TE flaps until released
FEEL DIFF PRESS (light)
Armed when the TE flaps are up or down
Illuminated (amber)
- indicates excessive differential pressure in the elevator feel computer
Note: Excessive differential pressure can be caused by erroneous activation of the Elevator Feel Shift module
SPEED TRIM FAIL (light)
Illuminated (amber)
- indicates failure of the speed trim system
- indicates failure of a single FCC channel when MASTER CAUTION light recall is activated and light extinguishes when Master Caution System is reset
MACH TRIM FAIL (light)
Illuminated (amber)
- indicates failure of the mach trim system
- indicates failure of a single FCC channel when MASTER CAUTION light recall is activated and light extinguishes when master caution is reset
AUTO SLAT FAIL (light)
Illuminated (amber)
- indicates failure of the auto slat system
- indicates failure of a single stall management/yaw damper (SMYD) computer when illuminated during MASTER CAUTION recall and extinguishes when master caution system is reset
Stabilizer Trim Wheel
- provides for manual operation of stabilizer
- overrides any other stabilizer trim inputs
- rotates when stabilizer is in motion
FLAP Lever
- selects position of flap control valve, directing hydraulic pressure for flap drive unit
- position of the LE devices is determined by selecting TE flap position
- Flap lever positions 30 and 40 arms the flap load relief system
Flap Gates
Prevents inadvertent flap lever movement beyond:
- position 1: to check flap position for one engine inoperative go-around
- position 15: to check flap position for normal go-around
Flap Position Indicator
- indicates position of left and right TE flaps
- provides TE flaps asymmetry and skew indication
FLAP LOAD RELIEF (light)
Illuminated (amber)
- if flaps are set at 40 > flaps retract to 30 due to excess airspeed
- if flaps are set at 30 > flaps retract to 25 due to excess airspeed
Leading Edge Devices (LE DEVICES) Annunciator Panel
Indicates position of individual LE flaps and slats
Leading Edge Flaps Transit (LE FLAPS TRANSIT) light
AMBER:
- any LE device is transit
- any LE device not in programmed position with respect to TE flaps
- a LE uncommanded motion condition exists (two or more LE flaps or slats have moved away from their commaded position)
- during alternate flaps extension until LE devices are fully extended and TE flaps reach flaps 10
Note: light is inhibited during autoslat operation in flight
Leading Edge Flaps Extended (LE FLAPS EXT) light
Green
- all LE flaps extended and all LE slats in extended (intermediate) position (TE flaps positions 1,2 and 5)
- all LE devices fully extended (TE flap positions 10 through 40)
The primary flight controls are linked (blank) to (blank) powered control units which command the primary flight control surfaces (ailerons, elevators, rudder)
mechanically / hydraulically
Can either HYD system power the flight controls entirely ?
yes
Can the ailerons and elevator be operated manually?
yes
The secondary flight controls are powered by what HYD system? (TE/LE flaps, LE slats)
HYD B
If system B fails how are the TE flaps operated ?
Electrically
Is there a rigid connection between the rudder pedals?
yes
Pitch control is provided by?
2 elevators
a moveable horizontal stabilizer
Roll control is provided by?
2 ailerons
8 flight spoilers
During takeoff, the rudder becomes aerodynamically effective between?
40-60kts
The captains control wheel is connected to cables to the (Blank) through the (blank) feel and centering unit
PCU’s / aileron
The first officers control wheel is connected to cables spoiler (blank) through the (blank) mixer.
PCU’s / spoiler
When you use the dual aileron trim switches what happens?
The trim electrically repositions the aileron feel and centering unit, which causes the control wheel to rotate and redefines the aileron neutral position
The pitch control surfaces consist of (blank) powered elevators and an (blank) powered stabilizer.
HYD / elevators
The stabilizer is controlled by (blank) trim or (blank) trim
autopilot / manual
Cables connect the pilots control columns to elevator (blank) which are powered by HYD System(s)
PCU’s and HYD system a and b
Describe the elevator feel system
- The elevator feel system provides simulated aerodynamic forces using airspeed (elevator pitot system) and stabilizer position
- feel is then transmitted to the control column by the elevator feel unit and centering unit
- the elevator feel system uses either HYD A or B pressure, whichever is higher
- When either HYD system or elevator feel pitot system fails, excessive differential power is sensed in the elevator feel computer and the FEEL DIFF PRESS light illuminates
Mach trim system. what is it / how does it work?
- Mach trim system provides speed stability at speeds .615 or higher by adjusting the elevators with respect to the stabilizer
- Mach info is taken from the ADIRU to move the mach trim actuator which repositions the elevator
What is the Speed Trim System and what is its purpose
Its designed to improve flight characteristics during operation with low gross weight, aft center of gravity and high thrust when the autopilot is not engaged.
the purpose of the STS is to reutrn the airplane to a trimmed speed by commanding the stabilizer in a direction opposite the speed change
How do the rudder pedals move the rudder?
the pedals are mechanically connected by cables to the input levers of the Main and Standby Rudder PCU’s.
The main PCU’s consist of two independent input rods, two individual control valves, and two separate actuators; 1 for A and 1 for B.
the standby pcu is controlled by a separate input rod and control valve and powered by the standby system
All 3 input rods have an override mechanism to allow the other available rods to input commands
After 135kts why does the MAIN PCU reduce pressure in the HYD A and B system ?
It reduces pressure by 25% to limit full rudder authority in flight after takeoff and before landing
What is the point of the FORCE FLIGHT MONITOR (FFM)
The FFM is located with the MAIN PCU and detects opposing pressure between A and B actuators; occurs if either system A or B is jammed or disconnected.
The FFM automatically turns on the Standby HYD pumo, opens the standby rudder shutoff valve to pressurize the standby rudder PCU and illuminates STBY RUD ON, Master caution and FLT CONT
How many Yaw dampers are there? how are they controlled?
Main and Standby // (SMYD) stall management yaw damper computer
During normal operating how is the yaw damper system HYD powered?
system B
When will the Yaw Damper automatically kick off and not be usable again?
SMYD senses a yaw damper system fault
SMYD senses that the yaw damper does not respond to a command
B FLT CONTROL switch is positioned to OFF or STBY RUD
Is yaw damper available during loss of both HYD systems?
Yes it is available through the standby yaw damper
HYD A powers what portion of the spoilers?
Ground spoilers (1,6,7,12)
What happens when speedbrakes are used in a turn?
increased roll rate
Compression of any landing gear strut enables the flight spoilers to deploy. Compression of what specific landing gear strut enables ground spoilers to deploy?
the right main landing gear
IF the speedbrakes are not armed (down position) during landing or RTO what conditions will cause the speedbrake to automatically deploy?
Main landing gear wheel spin up (more than 60kts)
both thrust levers are retarded to idle
reverse thrust levers are positioned for reverse thrust
LE devices consist of how many flaps and slats?
two flaps inboard and 4 slats outboard of each engine
What flap positions increase lift? what flap positions increase drag?
1-40 produce lift // 15 - 40 lift and drag
FLAP and SLAT sequencing
1,2,5 = LE flaps to full extended position, LE slats to the extended position, TE flaps to the commanded position
5-40 = LE flaps remain full extended, LE slats to the full extended position, TE flaps to the commanded position.
When will Flap Load relief happen?
Flaps 40:
- retract to 30 if airspeed exceeds 163 kts
- re-extend when airspeed is reduced below 158 kts
Flaps 30:
- retract to 25 if airspeed exceeds 176 kts
- re-extend when airspeed is reduced below 171 kts
What is the autoslat system? how is it powered?
At flaps 1,2 and 5 an autoslat function is available that moves the LE slats to full extended if the airplane approaches a stall condition
it is powered by HYD B, alternate is the PTU through system A
Can the LE devices be retracted using the alternate extension?
no
