Flight Controls

Question 1

All flight controls. except the ailerons, are controlled how?

Answer 1

Electronically using fly-by-wire technology.

Question 2

How are the Ailerons controlled?

Answer 2

Conventional control cables, and hydro-mechanical actuators.

Question 3

Which flight controls are Hydraulically Actuated?

Answer 3

• Primary flight controls
• Multi function spoilers
• Ground Spoilers

Question 4

Which flight controls are Electrically Actuated

Answer 4

• Horizontal stabilizer
• Flaps
• Slats

Question 5

What components make up the fly-by-wire system?

Answer 5

• Pilot interface (yoke, flaps / slat handle)
• Actuator control electronics (ACE) units
• Flight control modules (FCM) computers
• Flight control surface

Question 6

What is the function of an ACE (actuator control electronic)?

Answer 6

ACE units take the pilot control column inputs and translate that to the respective control surface.

Question 7

How many ACE units does the ERJ-175 have?

Answer 7

9 total

• 3 Primary ACE (P-ACE)
• 2 Slat / Flap ACE (SF-ACE)
• 1 Horizontal Stabilizer ACE (HS-ACE)
• 3 Spoiler ACE (S-ACE)

Question 8

What is the function of the P-ACE units?

Answer 8

They provide redundancy for the elevator and rudder.

Question 9

What is the function of the SF-ACE units?

Answer 9

They provide additional power to the Slat / Flaps (Think “LO RATE”

Question 10

What is the function of the S-ACE units?

Answer 10

They provide redundancy to all multi function and ground spoilers.

Question 11

Normal Mode allows what high level functions? (8)

Answer 11

• AOA limiting with elevator offset.
• Elevator control law scheduling with elevator.
• Auto-thrust compensation with elevator
• Rudder airspeed gain scheduling and stroke limiting
• Yaw damper and turn coordination via AFCS
• Rudder flight authority
• Roll spoiler scheduling with airspeed and speed brake deployment.
• Configuration change compensation with horizontal stabilizers due to speed brakes actuation.

Question 12

How is DIRECT MODE achieved?

Answer 12

By pressing the corresponding flight controls mode guarded button. (located between the MCDU’s

Question 13

What is lost in Direct Mode?

Answer 13

• FCM’s no longer translate pilot input to control surfaces.
• Flight controls have the same sensitivity regardless of airspeed.
• High level functions are no longer available.
• Loss of AOA limiting

Question 14

The rudder, elevator and stabilizer have how many controlling channels?

Answer 14

2 each

• Rudder : Upper and Lower
• Left elevator: Inboard and outboard
• Right elevator: inboard and outboard.

Question 15

How does the flight control system determine which channel is active?

Answer 15

It alternates even and odd days.

Question 16

Electric P-BIT

Answer 16

• Provides detection of out of tolerance conditions and failures in the FCM’s, P-ACE’s, and SF-ACE’s.
• Begins when AC power is 1st established.
• Last for 3 minutes
• 3 things can interrupt:
• -Interrupting AC power
• -Cycling a flight control mode button
• -Pressureizing any hydraulic system

Question 17

What does the elevator system consist of?

Answer 17

• 2 Independent, interconnected elevator sections (left & right)
• 4 PCU’s
• 2 P-ACE’s
• 2 Independent, interconnected control columns
• 2 Independent artificial feel units
• 1 Elevator control column disconnect handle

Question 18

ELEVATOR:

What is the purpose of the 4 FCM’s?

Answer 18

To provide high level function inputs to the ACE’s which include:

• Elevator control laws scheduling with airspeed (less deflection at higher airspeeds)
• Auto thrust compensation
• AOA limiting with elevator offset

Question 19

Which hydraulic systems provide power to the elevator

Answer 19

All 3

• System 1 powers left outboard PCU
• System 2 powers both inboard PCU’s
• System 3 powers Right Outboard PCU

Question 20

RUDDER:

What does the rudder system consist of?

Answer 20

• 1 Rudder surface
• 2 PCU’s
• P-ACE modules
• 2 Sets of adjustable rudder pedals

Question 21

RUDDER:

Which PCU, and which hydraulic system powers the Captains pedals?

Answer 21

The Upper PCU and Hydraulic system 1

Question 22

RUDDER:

Which PCU and which hydraulic system powers the F.O.’s pedals?

Answer 22

Lower PCU and Hydraulic system 3

Question 23

RUDDER:

What high level functions does the FCM provide?

Answer 23

• Yaw dampener
• Turn coordinator
• Gain scheduling as a function of airspeed (more deflection at lower airspeed)

Question 24

RUDDER:
In direct mode all high level functions are lost. How does the P-ACE module determine high speed or low speed gains?

Answer 24

Its determined by flap configuration:

• Slat / Flaps up - Less rudder deflection
• Slat / Flaps 1 or greater- more rudder deflection allowing the pilot maximum rudder authority

Question 25

AILERONS: | How are the ailerons controlled?

Answer 25

They use Cables and pulleys that control hydraulic PCU's attached to the ailerons.

Question 26

AILERONS: | How many PCU's do the ailerons have? What powers them?

Answer 26

Each aileron has 2 PCU's. - Left and Right inboard PCU's use hydraulic system 2 - Left and right outboard PCU's use hydraulic system 3.

Question 27

AILERONS: | IF the control wheel becomes jammed and must be disconnected, What does the Captain and F.O. command?

Answer 27

If the right aileron jams: - The captain commands the left aileron and multi-function spoiler pair #5. If the left aileron jams: The F.O. commands the right aileron and multi-function spoiler pair #4.

Question 28

HORIZONTAL STABILIZER: | What is the purpose of the horizontal stabilizer?

Answer 28

To control forces required on the elevator

Question 29

HORIZONTAL STABILIZER: | Stabilizer trim can be accomplished ___________ or through the _______.

Answer 29

Manually | FCM

Question 30

HORIZONTAL STABILIZER: | Trim priority logic?

Answer 30

- Backup Switches (Lower Pedestal) - Captain control wheel - First Officer control wheel - FCM (auto-trim) commands

Question 31

HORIZONTAL STABILIZER: | Pressing both sides of the trim switch for more than ____ seconds, stops moving the surface and trim is heard.

Answer 31

3 Seconds

Question 32

HORIZONTAL STABILIZER: IF half of the trim switch is pressed down for more than ____ seconds that switch is _______ and the aural "TRIM" is heard. Only MX can reset.

Answer 32

7 | Disabled

Question 33

HORIZONTAL STABIIZER: | Pitch trim runaway memory item

Answer 33

- A/P DISC BUTTON....PRESS AND HOLD - Pitch trim sys 1 & 2 cutout buttons.... PUSH IN. (Center Pedestal) Then QRC, Then QRH

Question 34

What is the purpose of the SLATs / FLAPs?

Answer 34

To increase lift for takeoff and landing.

Question 35

____ slat surfaces (___ per wing), and ____ doubled slotted flap surfaces (___ per wing)

Answer 35

8, 4 | 4, 2

Question 36

SLAT / FLAP: | Normal takeoff flap positions?

Answer 36

1, 2, & 4

Question 37

SLAT / FLAP | Normal landing positions

Answer 37

5, Full

Question 38

SPOILERS: | What purposes do they serve?

Answer 38

- Roll control - Speed Brakes - Ground spoilers

Question 39

SPOILERS: | How are: Roll control, Speed Brakes and Ground spoilers actuated?

Answer 39

- The FCM automatically commands the spoilers for roll control and ground spoilers. - The pilot manually actuates the spoilers using the speed brake handle.

Question 40

SPOILERS: | How many spoilers on the ERJ-175

Answer 40

5 on the upper surface of each wing.

Question 41

SPOILERS: | What do each of the spoilers do?

Answer 41

- The 2 inboard panels are dedicated ground spoilers. | - The 3 outboard spoilers are multi-function spoilers and can be used for all spoiler functions.

Question 42

SPOILERS: | How are the spoilers numbered

Answer 42

Starting inboard and moving outboard.

Question 43

SPOILERS: | Hydraulic systems 1 and 2 are used to actuate which spoilers?

Answer 43

- Hydraulic system 1 actuates spoiler pairs 2, 3, and 4. | - Hydraulic system 2 actuates spoiler pairs 1 and 5.

Question 44

SPOILERS: | In order for ground spoilers to activate what must occur simultaneously?

Answer 44

- Weight on wheels - Wheel speed > 45 KIAS or airspeed > 60 KIAS - Thrust Lever Angle (TLA)

Question 45

SPOILERS: | Are ground spoilers available in Direct Mode?

Answer 45

NO

Question 46

SPOILERS: | When are speed brakes automatically commanded closed?

Answer 46

- Flaps selected to 2 or greater. - Airspeed decreases below 180 KIAS - TLA > 70 degrees - Speed brakes are not available in direct mode.