CBT - Landing Gear

Question 1

When using landing gear gravity extention when there is not hydraulic power, what will happend to the landing gear doors after extention?

Answer 1

The landing gear doors will stay open

Question 2

Will NWS be available after L/G Gravity extention?

Answer 2

Yes in both normal and alternate modes

Question 3

What landing gear operation limitation exists if **Y HYD **fails?

Answer 3

Gear Retraction:
Only Nose gear full retraction is available.
Both BLG and WLG gear will stay extended and only the WLG doors will open.
WLG is prevented to retract even though it is powere by the G HYD as it may collide with the BLG

Question 4

What landing gear operation limitation exists if **G HYD **fails?

Answer 4

Only the BLG will fully retract since G HYD controls NLG and WLG

Question 5

Which HYD sys controls which gear

Answer 5

BLG doors and gear controlled by Y and WLG by G

Question 6

Which systems are related to the landing gear?

Answer 6

• The Landing Gear Extension and Retraction System (LGERS)
• The Brake Control System (BCS)
• The Steering Control System (SCS)
• The Tire Pressure Indicating System (TPIS)
• The Brake Temperature Monitoring System (BTMS), and
• The Oleo Pressure Monitoring System (OPMS).

Question 7

What is the main role of the Landing Gear Extension and Retraction System (LGERS)

Answer 7

• The opening/closure of the landing gear doors, and
• The extension and the retraction of the landing gears.

Question 8

How does the LGERS monitor/control and actuate the Landing gear?

Norma and Abnormal

Answer 8

Question 9

Where does the LGERS fall In the HYD architecture?

Answer 9

The LGERS is only pressurized during the extension and retraction phases, isolated from hydraulic pressure otherwise.

Question 10

What are the components of the LGERS?

Answer 10

The LGERS has two independent and redundant Landing Gear Control and Indication System (LGCIS) referred to as LGCIS 1 and LGCIS 2

they alternate after each gear retraction cycle

Question 11

From where does the L/G indicator panel (main instrument panel) get indications about gear uplock/downlock?

Answer 11

Only LGCIS 1 sends landing gear position data to the **L/G indicator panel ** using an additional and independent set of downlock proximity sensors.

These sensors are also electrically independent.

Question 12

Which system controls the L/G Gravity extention?

What caution exists with gravity extention?

Answer 12

Two Free Fall Control Modules (FFCM A and FFCM B) control the gravity extension of the landing gears.

The FFCMs are independent from the LGCIS

Non reversible incase normal extention fails and RESET shall not be done in flight

Question 13

What are the average timings for gear operation?

Normal and Gravity Ext

Answer 13

Normal 60s
Gravity Ext 70s

Question 14

At what speed is the gear extention inhibited?

Answer 14

The LGCIS receives airspeed data from the ADIRS to inhibit the extension of the landing gear above 280 kt.

Question 15

How is steering achieved on the A380?

Answer 15

• Nose Wheel Steering (NWS), and
• Body Wheel Steering (BWS).

Question 16

What is the role of the Body Wheel Steering?

Answer 16

On ground, the BWS reduces the loads on the BLG

Question 17

How many NWS modes are there?

Answer 17

• The normal NWS, and
• The alternate NWS when the normal NWS fails

Question 18

What HYD system powers normal NWS steering? What happens if it fails?

Answer 18

G HYD provides normal steering.
If the GREEN hydraulic supply fails, the alternate NWS activates automatically. The hydraulic power is supplied by:

• The LEHGS, and/or
• The NWS accumulator

Question 19

Is steering performance the same in alternate steering?

Answer 19

No, it is degraded. The damping of the steering handwheels automatically increases to prevent the flight crew from commanding excessive steering rates

Question 20

What supplies BWS in mode? And what happens if that system fails?

Answer 20

Yellow Hydraulic.
In case of a Y hydraulic failure, both BLGs are locked in the centered position by the locking mechanisms.

Question 21

Which FBW system controls and send alerts for the entire NWS and BWS system?

Answer 21

Wheel Steering Control System (WSCS)

With two redundant channels 1 & 2

Question 22

How does the BWS operate during pushback to reduce BLG stress when Y HYD is off?

Answer 22

Two Electrical Motor Pumps (EMPs), located on the Y hydraulic system, supply the BWS actuators during pushback

Question 23

When does the BWS automatically operate during taxi?

What is the maximum deflection for BWS

Answer 23

GS < 30 and NWS reaches 20

15 degrees

Question 24

What is the maximum pilot NWS tiller steering angle and autopilot/rudder angle?

Answer 24

Pilot 70 degrees
Autopilot/Rudder 6 Degrees