Landing Gear

Question 1

How is the gear held up?

Answer 1

Mechanical uplocks

Question 2

How are the landing gear bay doors opened?

Answer 2

Mechanically

Question 3

How is the gear held down?

Answer 3

Downlock springs

Question 4

What are the 3 ways to extend the gear?

Answer 4

• Normal - via gear handle
• Electrical override - electrical signal bypasses the PSEM
• Alternate - residual hydraulic pressure releases uplocks and gear free falls

Question 5

What must you do to get 3 green indication using the alternate gear extension?

Answer 5

Place the gear handle in the down position

Question 6

If the down/uplock sensors disagree, which one will be considered valid?

Answer 6

The one that agrees with the landing gear lever position

Question 7

Which hydraulic system provides pressure to the outboard brakes?

Answer 7

Hydraulic system 1

Question 8

Which hydraulic system provides pressure to the inboard brakes?

Answer 8

Hydraulic system 2

Question 9

If both hydraulic systems fail, is there a way to stop the airplane?

Answer 9

Yes, via the emergency parking brake

Question 10

What are some functions of the brake control modules (BCM)?

Answer 10

• Locked wheel protection
• Anti-skid protection
• Automatic wheel braking
• Touchdown protection

Question 11

When is locked wheel protection active?

Answer 11

Above 30 kts

Question 12

When is anti-skid deactivated?

Answer 12

Below 10 kts

Question 13

When is anti-skid not available?

Answer 13

For the emergency parking brake system

Question 14

What prevents the main landing gear from being retracted with the wheels spinning?

Answer 14

Automatic wheel braking

Question 15

What is touchdown protection?

Answer 15

Prevents the airplane from touching down with the main landing gear brakes applied

Question 16

When is touchdown protection deactivated?

Answer 16

• 3 seconds after WOW has sensed the ground or

* Wheel speed above 50 kts

Question 17

What supplies the emergency/parking brake?

Answer 17

Hydraulic system 1 and 2

Question 18

Where are the pressure accumulators for the emergency/parking brake system?

Answer 18

Isolated from both normal hydraulic systems

Question 19

How many brake applications are available from the accumulators?

Answer 19

6 full brake applications

Question 20

What supplies the nose wheel steering?

Answer 20

Hydraulic system 2

Question 21

Handwheel steering angle

Answer 21

• 76° until 40 kts

* Decreases to 7° at 100 kts

Question 22

What is the maximum rudder pedal steering angle

Answer 22

7°

Question 23

When is free wheel steering automatically activated?

Answer 23

• Air/ground system failure occurs
• Steering angle > 76°
• Steering system failure

Question 24

What are the two ways to disconnect the free wheel steering?

Answer 24

• Disconnect switch on yokes

* Disconnect switch on the external power connection

Question 25

How many weight on wheels (WOW) sensors are there?

Answer 25

• 6 total

* 2 on each wheel

Question 26

When will you get a green towing light?

Answer 26

• Steering disengaged
• Parking brakes not applied
• Main brakes not applied

Question 27

How many downlock/uplock sensors are installed?

Answer 27

• 12 sensors total

* 2 uplocks and 2 downlocks per landing gear

Question 28

When will the gear warning sound and can not be silenced?

Answer 28

•Flaps 5 or full regardless of thrust lever or radio altimeter

Flaps 0 thru 4
•RA below 700 ft AGL and
•Either thrust lever below 45° for 2 engines
•Thrust lever below 59° for 1 engine

Question 29

In the event of a dual radio altimeter failure when will the inhibit button silence the aural warning?

Answer 29

Only when flaps are between 0-4 positions

Question 30

How are the brakes operated?

Answer 30

Brake by wire

Question 31

Describe the landing gear indications

Answer 31

• Green - down and locked
• White - up and locked
• Amber - in transit
• Red - gear position and lever disagree