Landing Gear and Brakes Flashcards Preview

EMB 175 > Landing Gear and Brakes > Flashcards

Flashcards in Landing Gear and Brakes Deck (18)
Loading flashcards...

How is the landing gear extended and retracted?

Electrically commanded and hydraulically controlled.


When will the aural warning for the landing gear sound?

If the gear is not down and locked below 700FT RA with flaps at five or full and reduced TLA or any altitude with the flaps greater than five.


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

Only if both radio altimeters have failed.


What are the three landing gear extension modes?

* Normal.... LG lever DOWN
* Electric override........Bypasses the PSEM to directly command the selector valve.
* Alternate gear extension...... Manual uplock release opens free fall sequencing valve.


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

* Mechanically releases the landing gear lever lock.
* Lock protects agains inadvertent landing gear retraction on the ground.


What keeps the gear lock in position?

* Extended downlock springs.
* Retracted uplock hooks.


Describe the landing gear indications.

* Green.... Down and locked.
* White.......Up and Locked.
* Amber......In transist
* Red...... gear position and lever disagreement... 20 second grace period.


How do the landing gear doors actuate?

Mechanically, during landing gear extension or retraction.


how are the brakes commanded?

* Brake by wire.
* Electrically commanded and hydraulically actuated.
* Pedal position transducers send brake request to the BCM... Brake Control Module.


What Hydraulic systems provide brake pressure?

* System one..... Outboard
* System two..... Inboard.
* System one and two.... parking and emer brakes.


What brake protections are provided?

* Touchdown........No braking until three seconds or wheel speed of greater than 50 Knots.
* Anti skid.... Compares wheel speeds and releaes pressure... Inop less than ten knots.
* Locked wheel....Allows up to 33% differential braking for steering purposes.... Inop less than 30 Knots.


How many applications will the parking emer brake provide?



What stops the wheel from spinning during retraction?

* Mains...... BCM applies brakes after weight off wheels.
* Nose...... Snubbers in the nose bay.


What system controls the nose wheel steering?

Hydraulic two


What are the limits of the nosewheel steering?

Angle varies with ground speed.

* Up to 40 knots...... 76 degrees.
41 to 100 knots... Decreases from 76 to 7 degrees.


Location and purpose of prox sensors

Upper lower and middle...
Upper up and locked
Middle down and locked
Lower weight on wheels


Feedback sensors

Provide feedback on nose wheel steering angle and over steering.


What is the PSEM?

Proximity sensors electronics modules.