Study Guide Landing Gear & Brakes

Question 1

How is the landing gear extended and retracted?

Answer 1

Electrically commanded and hydraulically actuated

Question 2

When will the aural warning for the landing gear sound?

Answer 2

If the gear is not down and locked, and

-=5

Question 3

Can the landing gear aural warning be silenced by pushing the ‘LG WRN INHIB’ button?

Answer 3

Only if both altimeters have failed.

Question 4

What are three landing gear extension modes?

Answer 4

• Normal
  
  • LG lever DOWN
• Electric override
  
  • Bypasses PSEM to directly command command selector valve
• Alternate gear extension
  
  • Manual unlock release opens free fall sequencing valve

Question 5

What is the purpose of the DN LOCK RLS button on the landing gear lever?

Answer 5

• Mechanically release the landing gear lever lock

- Lock protects against inadvertent landing gear retraction when weight on wheels

Question 6

What keeps the gear locked in position?

Answer 6

• Extended Down lock springs

- Retracted Up lock hooks

Question 7

Describe the landing gear indications?

Answer 7

• Green Down and locked
• White Up and locked
• Amber in transit
• Red gear position and lever disagreement

Question 8

How do the landing gear doors actuate?

Answer 8

Mechanically, during gear retraction or extension

Question 9

How are the brakes commanded?

Answer 9

-Brake by wire
-Electrically commanded and hydraulically actuated
Pedal position transducers send brake requests to the BCM (Brake Control Module)

Question 10

What hydraulic system(s) provide brake pressure?

Answer 10

• HYD 1 Outboard brakes
• HYD 2 Inboard brakes
• HYD 1 & 2 Parking/Emerg brake

Question 11

What protections are provided for breaking?

Answer 11

Touchdown
-No braking until 3 seconds or >50 its wheel speed after touchdown

Anti Skid
-Compares wheel speed and released pressure

Locked Wheel
-Allows up to 33% differential braking for steering purposes

Question 12

How many applications will the parking/emergency brake provide?

Answer 12

-6 applications

Question 13

What stops the wheels from spinning during retraction?

Answer 13

Main Gear BCM applies brakes after weight off wheels

Nose Gear Snubbers in the nose bay stop the wheels

Question 14

Which hydraulic system controls the nose wheel steering?

Answer 14

HYD 2

Question 15

What are the limits for the nose wheel steering?

Answer 15

• Angle varies with ground speed
• up to 40 Kts
• 41 to 100 Kts Decreases linearly from 76 to 7 degrees