Flight Controls Flashcards
Which hydraulic systems can power all primary flight controls?
Normally, hydraulic system A and B power the flight controls redundantly; however the primary flight controls may be operated with only system A or B.
How are the primary flight controls operated in manual reversion?
The ailerons and elevators are operated manually via cable connections to the PCU’s, without hydraulic boost.
The rudder is operated by the Standby Hydraulic system, and the Yaw Damper is available.
The Spoilers are not available during manual reversion.
Which hydraulic systems power the trailing-edge flaps and leading-edge devices?
Trailing edge flaps & LE devices are powered by hydraulic system B.
System B failure-
LE devices are extended via standby hydraulic system
trailing-edge flaps are extended by an electric motor.
Once extended by the standby hydraulic system, the leading-edge devices may NOT be retracted
How is roll controlled with a jammed aileron?
The aileron transfer mechanism allows the pilots to identify which roll control is jammed.
With a jammed aileron, After breaking thru jam, First Officer controls roll by spoilers
The ailerons and Captain’s control wheel are inoperative.
How is pitch controlled with a jammed elevator?
An override mechanism allows the control columns to be physically separated from one another.
Applying force against the jam breaks out either Captains, or FO’s control column, freeing one to provide pitch control.
Pitch control may also be assisted by use of the electric stab trim
What does the illumination of the SPOILERS light indicate?
SPOILERS (amber) light indicates that the Spoiler Control Electronics Unit (SCE) has identified a spoiler system fault.
What happens when placing a FLT CONTROL switch to STBY RUD?
Activates the standby hydraulic system pump and opens the standby rudder shutoff valve to pressurize the standby rudder power control unit
How is the Elevator Jam Landing Assist activated?
To activate the system, the ELEVATOR JAM LANDING ASSIST switch must be selected ON and the actual TE flap position must be 1 degree or greater with the autopilot disengaged.
How is the horizontal stabilizer trim operated?
Normally operated by:
-Main Electric Trim
-Autopilot Electric Trim
(with a single motor)
- Manual Trim Wheel.
How is MCAS inhibited?
- MCAS may be overridden
by: - by positioning either stabilizer trim switch to CUTOUT or by forward control column cutout switches
Aft control column movement doesn’t stop MCAS nose-down stabilizer trim commands as the aft control column stabilizer cutout switches are bypassed. This ensures MCAS operations at high AOA
How is a failure of the Speed Trim or MCAS function indicated?
Illumination of the
SPEED TRIM FAIL (amber)
If one function fails, the other is inhibited
Can the Speed Trim system be overridden? If so, how?
By actuation of the control wheel trim switches (inhibits further Speed Trim operation for 5 sec.) or manual rotation of either stabilizer trim wheel.
Which systems help in identifying stalls and assist in control should one occur?
- Yaw Damper.
- Elevator Feel Shift
Module (EFS). - Speed Trim System.
When is rudder limiting active?
With both engines running and airspeed above 135 knots, both hyd. sys A and B pressure are reduced within the main PCU by approximately 25% each
*Rudder pressure will return to normal
system operating pressure when:
*an engine failure is detected, or
*airspeed is reduced below approximately 132 kts with both engines operating
What is required for the main yaw damper to activate?
- Yaw damper switch
selected ON. - Hydraulic system B is
powered.
-SMYD computers provide continuous system monitoring - IRS aligned.
What is the purpose of the Landing Attitude Modifier?
- Increased nose gear
clearance and drag.
*extra info
- With flaps 15-30 and
thrust levers near idle,
The Landing Attitude
Modifier extends the
speed brakes partially to
create additional drag.
- At flaps 30 and 40, the
Landing Attitude Modifier
deploys the flight spoilers
to reduce lift. This
additional drag requires
a higher angle of attack
to maintain lift, and
therefore, increases nose
gear clearance.
When is emergency descent speed brake active?
When the aircraft is above
FL300 and the Cabin
Altitude Warning is active.
EDS is activated automatically by moving
the SPEED BRK lever
when the system is
armed.
EDS raises the speed
brakes to a higher than
normal position when the
SPEED BRK lever is in the
FLIGHT DETENT.
EDS is deactivated when
the spoilers are stowed,
or when the cabin altitude
warning is no longer
active.
Under what conditions will the speed brakes stow automatically?
After an RTO, or landing, if either thrust lever is advanced, the Speed Brake lever automatically moves to the DOWN detent position and all spoilers retract.
When does the SPEEDBRAKES EXTENDED light illuminate?
- Illuminates for abnormal
speed brake operation - Illuminates in flight if the
SPEED BRK lever is
beyond the ARMED
detent and any of the
following conditions exist:- A thrust lever is greater
than 40 degrees for
more than 3 seconds or
idle for more than 15
seconds, or
- A thrust lever is greater
- TE flaps extended
>flaps 10, or
*Radio altitude < 800 ft
When does the PFD warning SPEEDBRAKE (red) along with an aural alert activate?
- If the speed brakes do not deploy after landing, or
- if the speed brakes do not deploy after a rejected take off above 80 knots.
When does the LE FLAPS TRANSIT light illuminate?
- Any time the leading-
edge devices are in
motion, or do not agree
with the scheduled flap
position.
The LE FLAPS TRANSIT light illuminates during slat-only movement, despite the name of the indication. This is because while the slats are in motion, they are in
a disagree with the scheduled LE device position. The light will also illuminate if there is uncommanded motion of two or more LE devices.
Which systems powers the alternate flap system?
The leading-edge devices are powered by the Standby hydraulic system, and the trailing edge flaps are powered by an electric motor
The ALTERNATE FLAPS position switch controls an electric motor that extends or retracts the TE flaps. The switch must be held in DOWN position to extend the flaps to the desired position.
There is no protection with an alternate flap extension
Are there flap protective systems available during an alternate flap extension?
No
What is the purpose of the flap load relief system?
- Protects the trailing edge
flaps from excessive air
loads. - When the Captains
indicated airspeed is too
high for the selected flap
setting, Flap Load Relief
activates and retracts the
TE Flaps to the next lower
setting below the selected
Flap Lever position. - The flap lever does NOT
move. - Reduction of airspeed
below flap limit will cause
Flaps to re-extend to
selected flap lever
position. - ie. Flap Blowback.
- Flap load relief is available when flaps are selected to: 10,15,25,30 or 40 degrees.
- Do not confuse with Load
Alleviation system.
