Flight Controls

Question 1

Which flight controls have some form of electrical actuation?

Answer 1

The stabilizer has two electric motors.

The slats have an electric motor.

Question 2

How many spoilers are used for roll control?

Answer 2

10 in total.

Question 3

How many ailerons are used for roll control?

Answer 3

4 total

Question 4

What is the number of spoilers used for speed brake and lift dumper/ground spoiler.

Answer 4

14

Question 5

How many slats are there?

Answer 5

14

Question 6

How many flaps are there?

Answer 6

4

Question 7

How many flight control computers are there and what are the types and numbers of each?

Answer 7

6 total

3 PRIMs

and

3 SECs

Question 8

How many flight control computers are required to safely control and land the aircraft and which types?

Answer 8

One of either type, PRIM or SEC, is required to control and land the aircraft.

Question 9

In normal operation, what is the name of the computer that computes and sends orders to the other computers?

Answer 9

The master.

Question 10

Each flight control is connected to ………………?

Answer 10

One PRIM and one SEC.

Question 11

Which PRIM is usually the master?

Answer 11

PRIM 1

Question 12

What is the sequence of allocation for the master PRIM if PRIM 1 fails.

Answer 12

PRIM 2 or if unavailable then PRIM 3

Question 13

If all PRIMs are unservicable which computer becomes master?

Answer 13

With no PRIMS online each SEC computes and executes its own orders.

There is no master.

Question 14

Which control laws do the PRIMs compute?

Answer 14

PRIMs compute all control laws, Normal, Alternate and Direct.

Question 15

Which control laws are computed by the SECs?

Answer 15

The SECs compute Alternate law when the PRIMs are failed.

Question 16

What is an FCDC and what does it do?

How many are there?

Answer 16

Flight Control Data Concentrator

These take information from the Flight Control Computers and make it accessable to other systems such as the Flight Data Recorders and Flight Warning System.

There are two FCDCs.

Question 17

In the event of total FCC failure, what system is in place to recover control?

Answer 17

The Backup Control Module takes over when all FCCs fail.

Question 18

What is an EHA?

Answer 18

An EHA is an Electro Hydrostatic Actuator.

It operates as a self contained hydraulic actuator receiving power from an electric supply.

Question 19

What is an EBHA?

Answer 19

An EBHA is an Electrical Backup Hydraulic Actuator.

This acts as a normal actuator when hydraulic supply is available.

If hydraulic supply fails it uses an internal pump and hydraulic reservoir to continue operation.

Question 20

How is elevator actuation organized?

Answer 20

Each elevator has one conventional actuator and one EHA.

The conventional actuator powers the elevator in normal operation with the EHA in damping mode as standby.

Question 22

Each flight control actuator is controlled by………?

Answer 22

One PRIM and one SEC.

Question 23

If all three PRIMS fail, which SEC becomes master?

Answer 23

There is never a master SEC. All SECS act independently/

Question 24

How does each PRIM use ISIS data?

Answer 24

To crosscheck data from the ADIRUs