Flight Controls Flashcards
How many groups of Leading Edge Flaps (LEF) on the 747, and how do they normally operate?
3 groups, Inboard, Midspan, and Outboard. Normally Pneumatically powered, however in Alternate mode, the LEF are electrically powered.
What are they groups of Trailing Edge Flaps (TEF), and how are they powered?
Inboard and Outboard. Inboard powered by HYD 1, and Outboard powered by HYD 4.
Is there flap asymmetry protection in alternate mode?
No.
How are the TEF driven in primary mode?
Hydraulically.
How long does the flap indicate on the Primary EICAS remain displayed after all flaps are up?
10 seconds.
What protection features do the Flap Control Units (FCU) provide for Trailing Edge Flaps in primary mode? (3 Items)
Asymmetry Protection,
Load Relief, and
Relays flap position information to the EICAS and other systems.
How many FCU’s are there?
3.
What is the maximum position of flaps attainable in alternate mode?
Flaps 25.
What EICAS message would be shown if all three FCU’s fail in their control function?
‘FLAPS CONTROL’
How does the Flaps Alternate Control work? (3 Items)
Bypasses the FCU’s,
All flaps controlled electronically, and
Manually selected.
Is there flap asymmetry protection in alternate mode?
No.
What happens if a primary control failure occurs in either Inboard or Midspan Leading Edge Flap group?
Both groups switch to secondary mode.
When do the spoilers extend to the up position after landing, if the speedbrake lever is NOT armed? (3 Items)
Engine 1 and 3 thrust levers at Idle,
Main landing gear on ground, and
Engine 2 or 4 thrust reversers in the idle position.
On the 747-8, to improve takeoff performance and reduce noise, outboard ailerons are deflected down at which flap settings? Return to neutral at which flap settings? Inboard ailerons droop at which settings? (3 Items)
10 or 20,
25 or 30,
10 or greater.
Describe the function of the Stab trim cutout switches in the ‘AUTO’ Position? (2 Items)
Provides hydraulic power to actuate stabilizer trim,
Cuts off hydraulic power if unscheduled trim is detected.
What is the effect on the flaps during operaton of the thrust reversers?
Inboard and Midspan LEF are retracted.
What surface component is moved when stabilizer trim inputs are made?
Leading edge of the horizontal stabilizer moves.
What is the purpose of Yaw Dampers? (2 Items)
To improve lateral and directional stability, and
Assist in turn coordination.
How does the Aileron Lockout system work, and what is its purpose?
At speeds above 238 kts, the outboard ailerons are locked in the neutral position, to prevent over controlling, and prevent structural damage.
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 tailstrike prevention activate?
When the PACS sense imminent tailstrike, it will decrease elevator deflection.
Takeoff Trim setting is calculated based on what? (4 Items)
Aircraft CG,
Gross Weight,
Takeoff Derate Selection, and
Takeoff Flap selection (747-8 only).
Will pushing the control wheel stabilizer trim switches with multiple autopilots engaged disconnect the AP system?
No.
