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Flashcards in FLIGHT CONTROL Deck (36)
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1

HOW THE ALTN PITCH WORKS?

In the normal mode, alternate pitch trim operates differently on the ground than it does in flight. On the ground, the stabilizer is directly positioned when the pilot uses the alternate pitch trim switches. In flight, the alternate pitch trim switches make changes to the trim reference speed

2

WHICH ARE THE PITCH ENVELOPE PROTECTION?

OVERSPEED

STALL PROTECTIONS

3

HOW MANY MODES THERE ARE FOR THE FLIGHT CONTROLS?

3

NORMAL
SECONDARY
DIRECT

4

HOW IS WORKING THE NORMAL MODE?

In the normal mode during manual flight (autopilot disengaged), four ACEs receive pilot control inputs and send these signals to three PFCs. The PFCs verify these signals and information from other airplane systems to compute enhanced control surface commands. These commands are sent back to the ACEs, then to the flight control surface actuators

When the autopilot is engaged, the autopilot system sends control surface commands to the PFCs. The PFCs generate control surface commands which are sent to the ACEs and then to the control surface actuators.

5

WHICH ARE THE FLIGHT ENVELOPE PROTECTIONS?

BANK ANGLE, OVERSPEED, BANK ANGLE PROTECTION

6

HOW IS OPERATING THE SECONDARY MODE?

The PFCs automatically revert to secondary mode when inertial or air data is insufficient to support normal mode or when all slat and flap position data is unavailable. The ACEs continue to receive and process pilot control inputs, and send these signals to the three PFCs. The PFCs use simplified computations to generate flight control surface commands. These simplified commands are sent back to the ACEs, where they are sent to the control surface actuators

7

WHICH FUNCTIONS ARE NOT AVAILABLE IN SECONDARY MODE?

AUTOPILOT

AUTO SPDBRAKE

ENVELOPE PROTECTION

GUST SUPPRESSION

PITCH COMPENSATION

ROLL/YAW ASYMMETRY COMPENSATION

TAIL STRIKE PROTECTION

8

WHEN AND HOW DOES THE DCT MODE WORK?

The ACEs automatically transition to the direct mode when they detect the failure of all three PFCs or lose communication with the PFCs.

Pilot inputs received by the ACEs are sent directly to the control surface actuators.

9

WHICH COMPENSATION IS PROVIDING THE PITCH CONTROL IN NORMAL MODE?

The PFCs provide pitch compensation by utilizing control surface commands to minimize airplane pitch responses to thrust changes, configuration changes (gear, flap, speedbrake), turbulence, and turns up to 30° of bank

10

PITCH TRIM HOW IS WORKING?

On the ground, the stabilizer is directly positioned when the pilot uses the pitch trim switches. In flight, the pitch trim switches do not position the stabilizer directly, but make inputs to the PFCs to change the trim reference speed. The trim reference speed is the speed at which the airplane would eventually stabilize if there were no control column inputs. Once the control column forces are trimmed to zero, the airplane maintains a constant speed with no column inputs. Thrust changes result in a relatively constant indicated airspeed climb or descent, with no trim inputs needed unless airspeed changes.

In the secondary or direct modes, primary pitch trim operates the same on the ground and in flight

11

HOW IT WORKS THE ELEVATOR VARIABLE FEEL ?

The PFCs calculate feel commands based on airspeed

12

TAIL STRIKE PROTECTION HOW IT WORKS?

During takeoff or landing, the PFCs calculate if a tail strike is imminent and decrease elevator deflection, if required, to reduce the potential for tail contact with the ground.

13

HOW MANY CHANNELS HAS THE STABILIZER?

Stabilizer position commands are processed through two independent channels within the flight control system

14

COLUMN CUTOUT FUNCTION

The column cutout function is designed to stop the effects of uncommanded pitch trim input from jammed or failed pitch trim switches.

2 SECONDS / 20 SECONDS

15

WHAT IS AN ( HLFC ) HYBRID LAMINAR FLOW CONTROL

The vertical stabilizer has a Hybrid Laminar Flow Control (HLFC) system installed to reduce aerodynamic drag

16

WHAT IS THE BANK ANGLE PROTECTION?

PROVIDES A ROLL INPUTS BACK TO 30 DEGREES IF THE BANK EXCEEDED 35 DEGREES.

ONLY ON PRIMARY MODE

17

HOW IT WORKS THE ROLL IN NORMAL MODE?

DOES NOT POSITION DIRECTLY THE SURFACES IN FLIGHT, INSTEAD COMMAND A ROLL MANEUVER AND THE FLIGHT CONTROL SYS WILL TRANSLATE IT IN SURFACE MOVEMENTS

18

HOW IS WORKING THE ROLL SECONDARY MODE ?

USING A SIMPLIFIED COMPUTATION

19

HOW IS WORKING THE YAW DAMPER CONTROL IN NORMAL MODE?

INSTEAD OF MOVING THE RUDDER IT WILL COMMAND A SIDESLIP

20

ASYMMETRY COMPENSATION

THE FLIGHT CONTROL ATTEMPTS TO MAINTAIN ZERO YAW RATE BY APPLYING AUTOMATICALLY RUDDER CORRECTIONS.

DURING REVERSE OPERATIONS OR TAKE OFF IN CROSSWIND.

IN FLIGHT IF ANY ASYM OCCURS THE SYSTEM TRY TO MAINTAIN A ZERO YAW AND SIDESLIP, AFTER THE FIRST ACTION WILL OFFLOAD EVERYTHING ON THE RUDDER.

21

WHAT IT FOR THE YAW DAMPING?

CONTROL DUTCH ROLL AND HELPING IN TURN COORDINATION

22

GUST SUPPRESSION

THIS FUNCTION ENHANCE THE RIDE QUALITY IN PRESENCE OF VERTICAL GUSTS AND TURBULENCE. WORKS IN VNAV OR ALT HOLD MODE ONLY.

ONLY IN NORMAL MODE

23

RUDDER TRIM

CONTROLLED WITH A SWITCH IN THE AFT AISLE STAND, HAS TWO RATES FAST AND SLOW,

ALL MANUAL TRIM INPUT ARE ZEROED ON TAKE OFF AND WHEN IN AUTOLAND IN LAND3 APPROACH

24

YAW CONTROL IN SECONDARY AND DIRECT MODE

DIFFERS FROM NORMAL MODE, USING SIMPLIFIED COMPUTATIONS, COMMANDING PROPORTIONAL RUDDER DEFLECTIONS

25

HOW MANY SPOILERS THERE ARE? AND HOW THEY ARE POWERED?

TOTAL OF 7 SPOILERS PER WING, 5 OF THEM POWERED BY HYDRAULICS, THE REMAINING TWO ELECTRICALLY

26

IN THE ARMED POSITION THE SPEEDBRAKE LEVER WHEN WILL MOVE TO UP?

WHEN THE MAIN GEAR WILL TRUCKS UNTILT AND BOTH THRUST LEVERS ARE NOT IN TAKE OFF RANGE

27

IF THE SPEEDBRAKE LEVER IS NOT IN ARMED POSITION WHEN THE SPOILERS WILL AUTOMATICALLY RAISE UP?

DURING RTO FOR EXAMPLE WITH SPEED ABOVE 85KTS AND BOTH THRUST REVERSED RETARDED TO THE IDLE REVERSE POSITION

28

SPEEDBRAKE EXTENDED AUTOMATICALLY RETRACT IF?

AFTER TOUCH DOWN THRUST LEVERS ARE ADVANCED,

TRANSITION BACK TO THE AIR

IN THE AIR WHEN TRUST LEVERS ARE 90% FWD

29

AUTODRAG

WORKS ONLY WITH FLAP 25 ORE GRATER TO INCTP THE GS FROM ABOVE, DEPLOYING THE SPDBRAKE PARTIALLY TILL 500 FT then stow them

30

When flaps are inhibited to avoid unwanted selection?

Above 20000 ft and above 260 kts