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Flashcards in Landing Gear & Brakes Deck (27)
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After retraction, how is the gear held up?

Gear is held up by mechanical uplocks. Up lock hook in over center position by springs, holding the gear even with hydraulic pressure off.


Which hydraulic system power the landing gear?

Center system


Is the system still pressurized with the gear retracted?



Can the gear be retracted after an alternate extension?

Yes, provided the center hydraulic system is functional.


What is the greatest angle the rudder pedals & tiller will turn the nose gear?

Rudder - 8 degrees
Tiller - 70 degrees


Which system powers the brakes? Is there a backup?

Brakes powered electrically by 28Vdc system. Backup is battery power.


How does alternate landing gear extension work?

Dedicated DC hydraulic pump releases uplocks using center system fluid. Landing gear free-falls in to down and locked position.
Gear lever position has no effect on alternate extension.
All hydraulically powered gear doors will remain open after extension.


With RTO selected, when would the brakes be applied?

-Airplane is on the ground
-Groundspeed above 85kts
-Both thrust levers retarded to idle


What will disarm the brakes after landing?

-Pedal braking applied
-Either thrust lever advanced
-Speedbrake lever moved down after speedbrakes have deployed
-DISARM or OFF selected on the autobrake selector
-Autobrake fault
-Normal antiskid system fault
-Loss of inertial data from the IRU's


Where are the brake temperatures displayed?

Synoptic GEAR page


How can the parking brake be confirmed as set?

By observing the EICAS memo message "PARKING BRAKE SET"


What is the "park and adjust" feature?

A feature which monitors the condition of the brakes after application and adjusts the clamping force as needed during brake cooling.


Is there an active force on the EBA's when the parking brake is set?

No, brakes are clamped on and no force required.


When does the autobrake application start on landing?

-Both thrust levers retarded to idle
-Wheels have spun up


Is there any limitation on the MAX AUTO brake selection?

Deceleration is limited to 4 until pitch angle is less than 1 degree


Above what value will the BRAKE TEMP indication change to amber and show the associated EICAS?
When does it change back to white?

5.0 or above
Changes back when all brakes are below 3.0


When is taxi brake release active?

787-8 - Below 70kts
787-9 - Below 30kts


When is the EICAS "TIRE PRESS" displayed?

-When any tire pressure is above or below the normal range.
-When there is excessive diff between two tires on the same axle.


How many Electric Brake Actuators are there per main wheel brake?

4 EBA's per wheel brake, 32 in total.


How many EBAC's are there?

4 Electric Brake Actuator Controllers. Each control a fore-aft wheel pair.


What happens when a wheel speed sensor senses a skid?

Brake pressure is reduced until skidding stops


Is antiskid provided for each individual wheel?



What data is used for touchdown and hydroplaning protection in the antiskid system?

Airplane inertial data


What data is used for locked wheel protection?

Comparison with other wheel speeds.


How long after the EICAS indication changes from UP to blank after retraction?

10 seconds


How can the isolation valves be controlled by the crew?

They can not


What is the purpose of the NGIV, RSIV and the AEIV?

Together with a reservoir standpipe in the center hydraulic system, the isolation valves will provide isolation functionality in the event of a leak. Flight crew will be able to extend the landing gear and have operational nose wheel steering on landing.