Flight Controls Flashcards
How many groups of leading flaps are provided, and how are they normally powered?
- 3 groups on each wing: outbard, midspan, inboard
-Normally pneumatically powered from the bleed air duct
What are the two groups of trailing edge flaps, and how are they powered?
-inboard and outboard
-inboard powered by hydraulic system 1
-outboard by system 4
Is there any asymmetry protection in alternate flap mode?
NO, there is no protection provided by the FCUs in alternate mode.
How are the trailing edge flaps driven in primary mode?
Hydraulically
How long does the flap indication on the primary EICAS remain displayed after all flaps are up?
10 seconds
What protection features do FCUs provide for trailing edge flaps in primary mode? (3)
-Asymmetry protection
-flap load relief
-flap position information to EICAS and other systems
How many Flap Control Units (FCUs) are provided?
(3)
What is the maximum extension of trailing edge flaps in alternate mode?
Flaps 25
What EICAS advisory message displays if all three FCUs fail in the control function?
FLAPS CONTROL
How does the Flap Alternate Control Mode work? (3)
-Bypasses the FCUs
-can be manually selected
- all flaps are extended or retracted by electronic motors
Is there any asymmetry protection in alternate flap mode?
NO
What happens if a primary control failure occurs in eitehr the inboard or midspan leading edge flap group
both groups switch to secondary mode
when do spoiler panels extend to the up position during landing if speedbrake lever is NOT armed?
-Thrust levers 1 and 3 near idle position
- main landing gear on ground
- reverse thrust levers 2 or 4 pulled up to the idle detent
747-8. To improve takeoff performance and reduce noise, outboard ailerons deflected down* at which flap settings?
They return to neutral position at which flap settings?
Inboard ailerons droop in which flap settings?
-10 or 20
-25 or 30
-10 or greater
Describe the function of the Stabilizer (STAB) Trim Cutout switches AUTO position.
- Supplies hydraulic power for stabilizer trim
- shuts off related system hydraulic power if unscheduled trim detected
What is the effect on the flap system during engine reverse thrust operation?
Inboard and Midspan leading edge flaps retract automatically
What surface component is moved when stabilizer inputs are made?
-Leading edge of moveable horizontal stabilizer
-Stabilizer trim varies the angle of incidence of the horizontal stabilizer
What is the purpose of the yaw dampers?
to improve airplane lateral and directional stability and provide turn coordination
How does the aileron lockout system work and what is it’s purpose?
Locks outboard ailerons in the neutral position at high airspeed.
-prevents over controlling at high speeds
What system assists the 747-8 in pitch stability and landing flare?
Pitch Augmentation Control System (PACS)
When does the 747-8 takeoff and landing tail strike protection activate?
PACS senses imminent tail strike decreasing elevator deflection
Takeoff Trim setting is calculated based on? (4)
-gross weight
-CG
-takeoff thrust derate selection
-takeoff flap selection (747-8 ONLY)
Will pushing the control wheel stabilizer trim switches, with multiple autopilots engaged, cause the autopilot to disconnect?
NO
-inhibited when multiple autopilots engaged
