021 05-00-00 Flight Controls Amend0

8/9/2019 021 05-00-00 Flight Controls Amend0

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TEXTBOOK

Flight Controls

020 00 00 00 AIRCRAFT GENERAL KNOWLEDGE

021 05 00 00 FLIGHT CONTROLS

RHLH

ELEVATOR

AILERON

TRIM

AIL

RUD

GND

12

20

32

12 10

GND

NU

ND

E

L

E

V

ROLL

FLAPS

ROLL

RUDDER

SYSTEM 1 / 3

FLIGHT

CONTROL

HYDR FUEL NEXTENGINE

RNG


2/40

Flight Controls

Infowerk for Training only Page 2

Table of Contents:

Flight Cont rols (construct ion and operation) _______________________________ 3

Primary Flight Controls _________________________________________________ 5

Secondary Flight Controls _____________________________________________ 24


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Flight Controls


Flight Controls (construct ion and operation)

As mentioned earlier four forces act upon an aircraft in flight in other words lift,

thrust, weight, and drag. These four forces are connected as follows.

Lift depends on the wing area and the forward speed.

The higher the speed the greater the lift will be. Drag depends on the area

expose to the airflow. It also increases with speed. Thrust depends on the engine

power available and the weight of the aircraft. In flight in other words with the

same power setting thrust increases as weight decreases.

At the same time the amount of lift required decreases as the weight decreases

to keep the aircraft in level flight.

LIFT

THRUST DRAG

WEIGHT

L

I

F

T

TIME

W

E

I

G

H

T

T

H

R

U

S

T


4/40

Flight Controls


An aircraft has three axis of control: the longitudinal axis, the lateral axis, and the

vertical axis.

The longitudinal axis runs along the center of the fuselage from the nose to the

tale. Movement about this axis is called rolling. The aircraft is set to roll.

The lateral axis run spanwise from wing tip to wing tip. Movement about this axis

is called pitching. The aircraft is set to pitch.

The vertical axis passes vertically through the center of the aircraft. Movement

about this axis is called yawing. The aircraft is set to yaw.


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Flight Controls


Primary Flight Controls

Flight controls are proudly classified into primary controls, and secondary

controls.

The primary flight controls are used to move the aircraft about one of the three

primary control axis.

The three primary flight controls and resulting movements are: ailerons for rolling

operated by rotation of the control wheel.

Elevators for pitch operated by fore and aft movements of the control column.

Rudder for yawing operated by the rudder paddles.

Mark the three primary flight controls


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Flight Controls


Longitudinal control is exercised by means of elevators.

These are hinge-mounted at the trailing edge of the horizontal stabilizer.

The elevators are operated by fore - and aft - movements of the control column.

In the neutral position of the control column the elevators are also at neutral.

The aircraft maintains a steady altitude.

If the control column is moved back, the elevator is moved up. This creates an

increase of down-force at the tail, making it move down.

This down-movement of the tail causes the nose of the aircraft to move upwards.

The aircraft assumes a climbing attitude.

If the control is moved forward the elevators move down.

There is an increase in stabilizer down-force, which causes the tail to move

upwards. When the tail moves up, the nose of the aircraft moves down and the

aircraft assumes a diving attitude.

The elevator is a displacement control device.

This means that pitch displacements are aposed by aerodynamic damping in

pitch and by the longitudinal stability. The response to an elevator deflection is a

steady change of pitch attitude.

This emplies that the elevators must be kept in a certain position to obtain an

maintain a certain pitch attitude.


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Flight Controls


Lateral control is exercised by means of ailerons which are hinge mounted to the

trailing edge of the wing.

In the control wheels neutral position the ailerons are also at neutral.

The aircraft maintains a steady lateral attitude wings level condition because

there is no difference between the lift of the left and that of the right wing section.

If the control wheel is moved to the right, the right aileron is displaced upwards

and at the same time the left aileron is displaced downwards.

The upgoing aileron reduces the lift at the right wing causing the wing to slightly

descent. The downgoing aileron increases the lift at the left wing which results in

an upgoing of the wing.

This causes a rolling moment to the right and the aircraft assumes a banking

attitude to the right.

The opposite effect is obtained if the control wheel is moved towards the left.


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Flight Controls


The ailerons are rate control devices.

This means that any rolling moment is always apposed by an aerodynamic

damping force.

A steady rate of roll is obtained when the actual rolling moment and aerodynamic

damping are in the state of balance.

To sum up movement of the aileron is only required to initiate a certain rate of

roll. When the required bank is reached they should be returned to neutral to

maintain the selected bank angle.

ROLLING MOMENT


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Flight Controls


Directional control is exercised by means of the rudder. It is hinge mounted to the

trailing edge of the vertical stabilizer.

The rudder is operated by moving the appropriate rudder paddles.

Pushing the left paddle moves the rudder to the left, pushing the right paddle

moves the rudder to the right.

In both cases the airflow behind the vertical stabilizer is changed, making the tail

move to the right or left.

The response of the aircrafts nose is into the opposite direction. I. e. into the

direction of the paddle used.

The rudder is a displacement control device.The yawing movement set up by a rudder operation is always opposed by

aerodynamic damping forces and in herend directional stability.

When these forces are in balance a steady state of yaw is kept up.

To sum up the rudder must be kept in a certain position to obtain a selected state

of yaw.

In practice the aircraft is turned with the combined effects of ailerons and rudder.

RUDDER PEDALS

RUDDER


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Flight Controls


The primary flight control systems of the Fairchild Dornier 328 Jet.

The aircraft primary flight control system consist of conventional ailerons,

elevators and rudder.

The primary control surfaces are moved manually by linkage systems consisting

of cables, pulleys, levers and rods.

The secondary flight controls consist of the aileron trim, the elevator trim and the

rudder trim systems and trailing edge flaps.


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Flight Controls


Dual controls in the cockpit are installed for the three primary flight controls.

In addition the elevator and aileron control runs are each equipped with a

disconnect unit which allows the captain's and first officer's controls to be

disconnected from each other should one control run become jammed.

The rudder pedals drive a Flettner-type spring tab on the trailing edge of the

rudder.

Dornier

328

Disconnect unit

Yokes

Conventional ailerons

Elevators

Disconnect unit

Pilot Co pilot

FLIGHT CONTROL SYSTEMS

At airspeeds up to 160 knots the rudder is

deflected by aerodynamic servo reaction from

the tab.

The rudder itself is not connected to the rudder

pedals directly except at airspeeds above 160

knots.

This arrangement limits the rudder deflection at

higher airspeeds


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Flight Controls


"Fairchild Dornier 328 Jet Aileron system"

The aircraft is controlled about the roll axis by a conventional aileron control

system.

The ailerons are operated manually by dual control wheels, or by signals from the

automatic flight control system (AFCS) when the aircraft is flying under automatic

control.

A Flettner-type servo tab, which provides aerodynamic assistance to reduce pilot

effort, is installed on each aileron.

The LH aileron tab can be electrically trimmed.

The linkage from the control wheels to the ailerons is an system of pulleys,

cables, quadrants, push-pull rods, levers and bellcranks.

pulleys, cables Quadrants


13/40

Flight Controls


push-pull rods levers

The captain's and first officer's aileron control runs are joined by a disconnect

unit.

This unit allows the two control runs to be separated by the application of higher

than normal input forces, should one control run become jammed.

The aileron linkage in the LH and RH wings is also mechanically connected to the

LH and RH roll spoiler actuators.

The maximum Aileron movement is 30 up and 25 down.

Bellcranks


14/40

Flight Controls


The position of each aileron is indicated by a blue synoptic on the FLIGHT

CONTROL page of the EICAS.

If the transmitter signal is invalid, the blue synoptic is replaced by an amber X.

Under normal operating conditions the LH and RH aileron synoptics are joined by

a white bar.

The bar changes to amber if the aileron disconnect unit is activated.

In addition, an aileron disconnected message will be displayed on the CAS field.

RHLH

ELEVATOR

AILERON

TRIM

AIL

RUD

GND

12

20

32

12 10

GND

NU

ND

E

L

E

V

ROLL

FLAPS

ROLL

RUDDER

SYSTEM 1 / 3

FLIGHT

CONTROL

HYDR FUEL NEXTENGINE

RNG


15/40

Flight Controls


"Dash 8 Elevator control system"

Pitch control consists of two independent elevator control circuits.

The Pilots control column operates the left elevator. The Co-pilots column

operates the right elevator.

The two control columns are normally interconnected, by a shaft.

So simultaneous movement of both elevators is provided.

In the case of a jamming elevator, the two systems can be disconnected from

each other. Limited pitch control is provided by the remaining elevator.


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Flight Controls


Each system consists of the control column, the output-quadrant, and a the cable

circuit. Routed in the under floor compartment, to the tail cone up in the vertical

stabilizer, to the terminal quadrant.

Please mark: the elevator, the push rod, the input lever and the torsion spring

The quadrant is connected to the elevator via a push rod, the input lever, and the

torsion spring. Via a torque tube, and a push rod, the elevator spring tab is

connected to the quadrant. A trim system is provided for each elevator.

ELEV

ATOR

TRI

M

TRIM LT.

EMERG

BRAKE

CONT.

LOCK

OFF

ON

UNFE

ATHER

START&

FEATHER

MIN

FUEL

OFF

P

ROP

MAX

MAX

REV

FLT

IDLE

P

OWER

DISC

N U

N D

TO PARK

35

15

10

5

0

FL

APS


17/40

Flight Controls


The two elevators are mounted independently of each other.

Each elevator is mounted on the trailing each of the vertical stabilizers.

The elevator horn on the outboard end, provides aerodynamically assistance.

The horn carries internal mass balance weights, to balance the elevator.

The horn is electrical heated to prevent ice build up.

Bumper stops are located on the inboard side, to limit the maximum deflection.

A spring-loaded gust lock latch is also secured to this fitting.

A spring tab is hinged to the inboard trailing edge of each elevator. The spring tab

provides aerodynamic assistance to the elevator movement.

With the aircraft on ground and the absence of air load the input movement from

the column, is transmitted directly to the elevator, via the torque shaft.

The elevator makes the full movement, and the spring tab moves just a little.

Aerodynamic assistance


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Flight Controls


In flight, air load on the elevator, opposes the input force of the pilot.

This produces a twisting movement on the torque shaft. Which is transmitted via

the torque tube to the spring tab.

The spring tab deflects in the opposite direction of the elevator.

Aerodynamic assistance is provided. Maximum tab deflection is limited by crank

stops. At further movement of the column the elevator is moved directly.

In the event of a jammed elevator, the left and right system can be separated by

the pitch disconnect system.

The system is controlled by a vertically mounted handle; on the center consol.

In normal position the clutch is engaged. A spring retains the clutch to the clutch

plate, to connect the pilots and co-pilots control columns positively.

Pulling the handle, draws back the clutch lever and cam assembly.

The turning calm pulls the clutch from the clutch plate. The two columns are now

separated and move independently.

Turning the handle 90 degrees locks it in this position. Turing the handle back 90

degress, and releasing the handle, allows the springs to force the clutch-to-clutch

plate. The clutch reengages if the column are aligned.

PITCH

Pitch Disconnect System


19/40

Flight Controls


"FD 328 JET Rudder control system"

The aircraft is controlled about the yaw axis by a manually operated rudder

control system. At low airspeeds the rudder is moved by the aerodynamic effects

of a Flettner-type spring tab located on the lower trailing edge of the rudder.

Movement of the rudder pedals drives the tab in the opposite sense to the yaw

command and aerodynamic effects from the tab move the rudder in the

commanded sense.

At airspeeds above 160 KIAS the spring tab is locked and therefore aerodynamic

assistance for rudder commands is no longer available.

The pedal assemblies are then effectively connected directly to the rudder and

flight crew commands are not assisted by the spring tab. This limits the rudder

deflection at high airspeeds and prevents structural overload conditions.

The spring tab can be unlocked and the limiter actuator disabled by manually

operating a switch in the flight compartment.

A facility for testing the actuator is also provided.


20/40

Flight Controls


The rudder control subsystem consists of the following components:

- LH and RH rudder pedal assemblies

- LH and RH pedal adjustment assemblies

- control cables, pulleys, rods, levers and bellcranks

- LH and RH forward quadrant assemblies

- pressure bulkhead fairleads


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Flight Controls


- aft quadrant assembly

- spring tab lever assembly

- torsion bars


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Flight Controls


- rudder limiter actuator

- TEST TAB LOCK switch/light

- RUD LIMIT switch/light

- rudder position transmitter

- various controls and indicators

TEST

TAB

LOCK

ENG SYNC

MSTR SEL

ENG MAINT

SEL

NORM MAINT NORM MAINT LH RH

LH RH

EXCEED

TREND

IMT/FDR

REFUEL QTY

+

-

LI

MIT

RUD

SPOIL

GND

RUDDER NOT LIMITED


23/40

Flight Controls


- various circuit breakers and control relays.

Rudder control system position indicating and fault monitoring is provided on the

EICAS and on the MFD flight control system page.

Rudder position indication is provided by the rudder position transmitter

potentiometer, which sends its signals to data acquisition unit 1 for processing.

The position of the rudder is indicated by a blue synoptic on the FLIGHT

CONTROL page.

If the transmitter signal is invalid, the blue synoptic is replaced by an amber X.

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28BUS 1 ESSENTIAL BUS BUS 2

ECS OXY

ICE ENG

ENG BLEED

LH

ECS PACK

LH

FLOW MODE

PRI(X2)

CAB TEMP

CTL

O XY G I CE PR OT

AIRFCYCLE

WIPER

LH

WS HEAT

SIDELH

VIB MTR

LH

MLS

1

AOA

HEAT LH

EL HORN LH

RUDHORN

PITOT

HETLH

DE ICE

PRESSLH

BLEEDLEAK

DETLH

X BLEED

AUX(X3)

BLEEDLEAK

DETRH

DEICE

PRSS RH

ICE

DET

ICE PROT

AIRFSGL

TAT

HEAT

WS HEAT

FRONTLH

WS HEAT

SIDE RH

ENG A-ICE

LH

PROXI

A/1

PROXI

B/1

LDG LTS

RH1

LDG LTS

RH2

AVIONICS

ELEC

AVIONICS

FLCOM/NAV

HYD LTS

CPCS ENG

ECS PROXI

ENG ICE

AVCLTS

FUEL FIRE

A

COM

2

ADF

1

AUDIO

3

FMS

CDU

STBYRUD

LIMIT(B12)

STBY AIL

TRIM(B10)

STBYELEV

TRIM(B9)

ELEV

TRIM(B7)

AIL

TRIM(B6)

RUDDER

TRIM

RUDDER

LIMIT(B5)

GNDSPOIL

B

GNDSPOIL

B FLAPS

HGS

OHU

HGS

HCP

HGS

COMP

RADALT

1

CLRDLY

HEAD

NAV

1

DME

1

ATC

1

COM

1

PAX

BRIEF

PAX

ADDRESS

AUDIO

1

IAC

2

ADC

2

LDGLTS

LH1

LDG LTS

LH2

DIMMER

AUX(V5)

NAV

LTS

CAB PRSS

PRI(X7)

TTO 1

LH

TTO 1

RH

FADECB

LH

HYDSTBY

PMP AUTO

HYDSTBY

PMP MAN

HYDPRSS

IND A

B RK CO V HY DPRS S

IND B

OIL PRSS

LH

FADEC A

LH

CONTIGN

INDLH

IGN

LH

STARTB

LH

START A

LH

STARTA

RH

STARTB

RH

IGN

RH

CONT IGN

INDRH

FADEC A

RH

OIL PRSS

RH

CAB PRSS

DUMP

CAB PRSS

BACKUP

FADECB

RH

REFUEL

RH

NRMA-SKID

PRIM

NWS AP SERVO YD

SERVO

WARNPANEL

PRI(X7)

WARN PANEL

AUX(X7)

NRMA-SKID

PRIM

ALT A-SKID

SEC

GEAR

RETRACT

GEAR

EXTEND

FUEL

XFEED LH

ELPMP

LH

JETPMP

LH

FUEL SOV

LH

FIRE DET

LH

FIRE BOT

LH

APUFIRE

DET

APU FIRE

BOT

FIRE DET

RH

FIRE BOT

RH

FUEL SOV

RH

JET PMP

RH

ELPMP

RH

FUEL

XFEEDRH

DAU

CH2B

AHRS2

PRI(F2)

STBY

ATT

STBY

ALT/ASI

STBY

INSTLTS

CLOCK

1

EM

PWR

GCU

2

RMU1

PRI(23)

DAU

CH 1B

DAU

CH 2A

PFD

1

MFD

1 EICAS

IAC

1

ADC

1

FD/AP&DISP

CTL1

TONE

GEN1

BACK-UP

BATT

AOA/STALL

WARNLH

DCTIE

IND TRU

INV

1

RMU1

AUX(A7)

RMU2

AUX(U1)

AHRS1

AUX(F1)

IRS2

AUX(M5)

PFD

2

MFD

2

DAU

CH1A

LTS LDG

APLTS

FUEL LDG

APLTS

AVIONICS

COMNAV FL

AVIONICS

ELEC

B

C

D

E

A

B

C

D

E

5 2 2 2 3 2 10 2 2 2 1 0 2 10 2 21 1 2 2 2 15 2 2 7,5 5 5 3 20

3 20 15 3 3 10 10 3 3 3 3 35 1 3 2 55 7,5 7,5 7,5 7,5 5 2 3 1 3 1 3

3 5 5 7 ,5 3 3 3 5 5 3 3 3 2 5 2 1 3 3 3 2 3 3 1 2 2 5 3 1 5

10 2 2 5 5 3 3 3 3 3 5 3 3 7,5 1 2 7,5 2 1 5 2 5 10 2 7,5 2 10 1

152 2 2 1 15 10 5 1 1 1 15 15 15 10 1 3 1 15 3 3 7,5 15 5 5 5 5 15

22 21

C ABIN 1 20 0 F T

22 C 50 FPM

END

MAINCOPY

NU

ND

0 0

0.0 0.0

N1

ITT

N2

22 21

0.0 0.0

OIL

TEMP

OIL

PRESS

FF LBS/HR

FQ LBS0C

0 0

750

REF

DATA

AHRSMSG

RUDDERLIMIT FAIL

Rudder position transmitter

potentiometer

EICAS MFD (MultiFunction Display)


24/40


25/40


26/40


27/40


28/40

Flight Controls


On the Boeing 707 fore- and trailing flaps are one unit with a fixed slot.

The flap assembly extends along a curved rail.

The lower flap shroud on the wing is hinged and moves upward to improve the

airflow through the slot during flap extension.

The Cessna, as an example of a small aircraft, uses a dual roller system on the

single flap support arm.

These two rollers follow individual slots in a guide rail.

The upper and lower slots are initially parallel which allows aft movement of the

flap.

Towards the last third of the travel the upper slot is curved down and the lower

curved up which deflects the flap downwards.


29/40

Flight Controls


A single, cockpit-operated, electric motor drives a single screw jack connected to

control rods. A cable circuit assures symmetrical operation on both wings.

"Slats and leading edge flaps"

A wind tunnel experiment shows us the need for high lift devices on the leading

edge. Smoke is used to visualise the airflow over a flat plate.

Using a bend in the plate to simulate flap deflection the smoke trail is deflected

downwards.

As a result of the so-called pre-orientation of flow the airflow ahead of the plate is

also deflected downwards. This increases the angle of attack and especially on

fast airfoils with a small nose radius can lead to an early stall. To reduce this

effect leading edge flaps or slats are commonly used.

Flap 0

Forward roller

Aft roller FLAP

Control cables

Control rods

Fowler Flaps

Flap select leverElectric Motor

Screwjack

CESSNA


30/40

Flight Controls


"Leading edge flaps"

Leading edge flaps fold down when the trailing flaps are lowered.

The drooped leading edge is hinged at the bottom and when extended maintains

a smooth surface on top of the wing.

The Kruger flap is a hinged panel hinged slightly aft of the leading edge.

During extension an additional hinged portion folds out and forms a new leading

edge.

Both types of leading edge flaps actively increase the camber of the wing. Both

devices can be operated by hydraulic actuators or mechanical screw jacks.

SMOKE TRAIL

SMOKE JET

MARKER

PLATE

SMOKE TRAIL

SMOKE JET

MARKER

PLATE


31/40


32/40


33/40

Flight Controls


The flap control system is operated by the flap selector.

The detente cam provides settings from 0 degree in the full forward position, via

5, 10, and 15 degrees to 35 degrees in the full aft position.

To change the flap setting, the trigger must be pulled, to lift the cam follower.

At the next position the trigger must be released.

The cam follower will engage in this position.

The Quadrant transmits the movement via a cable circuit to the hydraulic flap

power unit.

The cable circuit is routed from the cockpit under-floor, up behind the copilot to

the ceiling. and in the ceiling backwards to the center wing area, up to the flap

power unit.


34/40

Flight Controls


The flap drive system consists of the flap power unit, the primary drive system

and the secondary drive system.

Four ball screw actuators in each wing drive the flaps.

One transfer gearbox on each side, connects the secondary drive to the primary.

The torque sensor unit will illuminate a caution light, if the secondary drive is

used.

Five flap tracks, on each wing support the flaps.

COUPLING TORQUE

SENSOR

COUPLING

SECONDARY

DRIVE

OUTBD

FLAP

INBD

FLAP

INBD

FLAP

OUTBD

FLAP

POSITION

SENSOR

NO. 4

BALLSCREW

ACTUATOR

NO. 3

BALLSCREW

ACTUATOR

NO. 2

BALLSCREW

ACTUATOR

NO. 1

BALLSCREW

ACTUATOR

NO. 2

BALLSCREW

ACTUATOR

NO. 3

BALLSCREW

ACTUATOR

NO. 4

BALLSCREW

ACTUATOR

POSITION

SENSOR

COUPLING TRANSFER

GEARBOX

TRANSFER

GEARBOX

PRIMARY

DRIVE

INPUTPULLEY

FLAP POWERUNIT

RIGHT WINGLEFT WING


35/40

Flight Controls


"Dash 8 Spoiler control system"

The roll spoilers augment the ailerons in providing lateral control.

They are hinged to the trailing edge of the wing.

The spoilers extend 75upwards when fully deflected.

The system is hydraulically operated by the number 1 system for the inboard

spoilers, and the nr. 2 system for the outboard spoilers.

The spoilers rise in parallel with the up-going aileron.

At speeds above 140 knots only the inboard spoilers operate.

The spoilers are controlled from the pilot's control column.

Rotary movement of the pilot's control wheel is

transmitted by a chain and sprocket mechanism

to a lever on the base of the column.

The lever is connected to the spoiler quadrant via

a push rod.

The quadrant integrates a tension regulator.

The tension of the roll spoiler cable to the splitter

quadrant is maintained constant under all

temperature conditions by the tension regulator.


36/40

Flight Controls


"Ground spoilers and speed brake system of the Embraer 145"

The outboard surfaces provide the speed brake and ground spoiler functions,

while the inboard surfaces provide only the ground spoiler function.

The spoiler surfaces are made of composite material, and the subsystem is

hydraulically actuated and electrically controlled.

The control of the ground spoiler function is automatic during the landing and

rejected take off.

The speed brake function is controlled by the pilot.

The operation of the ground spoiler is automatic during the landing and rejected

takeoff procedures.

With the aircraft on ground, the ground spoiler logic receives the first signal from

the landing gear proximity switches.

When the wheel speed gets up to 25 knots of the turning speed, the speedsensor sends the second signal.

When the pilot moves the two thrust levers to below 30, the spoiler control unit

will operate the spoiler surfaces to open.

CHECK

TO CONFIG

PRESSANDPULL

PRESSANDPULL

AILDISC

ELEVDISC

2222

UP

DOWN

0

9

18

45

18

45

9

0

FLAP

EMERG/PARKBRAKE

PULL

AND

ROT

ATE

CLOSE

OPEN

SPEED BRAKE

MAX

THRUSTSET

IDLE

GUSTLOCK

GO AROUND GO AROUND


37/40

Flight Controls


The indications of the spoilers on the EICAS display are:

To operate the speed brake, the aircraft must have engine thrust lever angles

below 50, flaps set to 0and the airspeed below 202 knots IAS.

In these conditions, when the pilot operates the speed brake lever, the spoiler

control unit commands the outboard spoiler surfaces to open.

If one of these conditions does not occur, and the pilot operates the speed brake

lever, the EICAS display will show the caution message SPEED BRAKE LEVER

DISAGREE and the surfaces remain closed.

0

AA

KG KG

ALT T/0 1

35.035.0

103% 630

1210

0.0

70708686

1500 1500

55 55

490490

450 450

DN DNDN

0 2

END

KGH KGH

The spoiler OPEN or CLOSED

indicating the surfaces condition.

The SPOILER FAIL indicates a

failure found in the spoiler control

unit.

There is also an aural warning

message TAKE OFF SPOILER

when the pilot tries a takeoff withthe spoiler surface open


38/40


39/40

Flight Controls


A trim tab is mounted on the outboard trailing edge of each elevator.

The trim tab is operated manually from the trim hand-wheel, on the center consol.

The movement is transmitted via chains to the cable circuit in the under-floor

compartment, to the tail cone.

Up in the vertically stabilizer, to the horizontal stabilizer.

The trim actuator converts the rotary movement of the cable in a linear

movement, to adjust the trim tab.

Elevator trim indication is accomplished mechanically. A spiral on the inside face

of the pilots hand-wheel converts rotary movement to linear movement of the

pointer.

Elevator Trim Tab System


40/40

Documents

021 05-00-00 Flight Controls Amend0