Landing Gear & Brakes Flashcards
Landing Gear and Brakes
Which hydraulic system supplies power for retraction, extension, and steering ?
The CENTER Hydraulic system.
Landing Gear and Brakes
How is the brake system powered ?
ELECTRICALLY.
It’s an Electro-mechanical brake system powered by the 28 V DC bus and main battery
Landing Gear and Brakes
How are the brakes controlled ?
The Electro-mechanical brake system is controlled by
4 Electric Brake Actuator Controllers (EBACs).
They trigger the Electric Brake Actuators (EBAs) on each wheel brake.
Landing Gear and Brakes
What deflection to the nosewheel does the rudder pedals provide ?
8° in either direction.
Landing Gear and Brakes
Above which speed is the auto brake available for a rejected takeoff ?
85 kts
Landing Gear and Brakes
What is the speed limitation for Gear extension and retraction ?
Same speed :
270 IAS / 0.82 Mach
Landing Gear and Brakes
What deflection does the nose wheel steering tiller gives ?
70° in either direction, summed with rudder pedal steering inputs (but still limited to 70° of travel).
Landing Gear and Brakes
Landing gear doors symbology :
What does a white crosshatch rectangle indicate ?
The gear is in transit.
Landing Gear and Brakes
Landing gear doors symbology :
What does a blank white rectangle indicate ?
The door signal is invalid.
Landing Gear and Brakes
What is the Brake temperature indication range ?
From 0.0 to 9.9 in increments of 0.1
EICAS Advisory message BRAKE TEMP is displayed above 4.9
Landing Gear and Brakes
Are there any air-ground logic sensors on the nosewheel beam ?
NO
The sensors are only on the main landing gear beams.
Landing Gear and Brakes
How do landing gears move during normal gear extension ?
The landing gears freefall without hydraulic power to the down and locked position.
Landing Gear and Brakes
How many brake actuators are there per wheel ?
There are 4 Electric Brake Actuators (EBAs) on each main landing gear wheel brake.
Landing Gear and Brakes
What controls the Electric Brake Actuators (EBAs) ?
The EBAs are controlled by an Electric Brake Actuator Controller (EBAC).
There are 4 EBACs that each control the brake force of a fore-aft wheel pair.
Landing Gear and Brakes
Are all brakes always simultaneously applied ?
NO
if wheel speeds are less than 70 kts, each manual brake application applies one half of the brakes on each main landing gear, alternating between wheel pairs at each brake application.
Note : the brake pedal must be fully released to transition to the other two brakes on a main landing gear.
Landing Gear and Brakes
When are ALL active brakes applied by an action on the rudder brake pedals ?
- Heavy brake application
- Landing rollout
- RTO
- Parking brake
Landing Gear and Brakes
When is the EICAS advisory message TIRE PRESS displayed ?
- Any tire pressure is above or below normal range
- There is an excessive pressure difference between two tires on the same axle.
Landing Gear and Brakes
When does autobrake application begin ?
After landing when :
- Both thrust levers are retarded to idle and,
- The wheels have spun up.
Landing Gear and Brakes
Can the autobrake selector move on its own ?
YES
- When the autobrake system disarms after landing, the autobrake selector automatically moves to the DISARM position.
- When the autobrake system disarms during takeoff, the autobrake selector will automatically move to OFF after takeoff.
Landing Gear and Brakes
What powers the landing gear extension during an ALTERNATE extension ?
- A dedicated DC powered hydraulic pump and CENTER hydraulic system fluid unlock the Gear,
- The struts then freefall by gravity.
Landing Gear and Brakes
What causes the autobrake system to disarm ?
- Pedal braking is applied,
- Either thrust lever is advanced after landing,
- Speedbrake lever is moved to the DOWN detent after they have deployed on the ground,
- the DISARM or OFF position is selected on the autobrake selector,
- An autobrake fault,
- A normal antiskid system fault,
- A loss of inertial data from the IRUs
