Landing Gear and Brakes Flashcards
NWS limits for the tiller and rudder?
Tiller ±75º, rudder ±7.5º
How should brake wear indications be checked?
Parking brake applied and HYD SYS 3 pressurized
When is gear warning horn mutable?
In secondary mode with one throttle idle
Function of gear warning HORN switch?
Disable gear warning under certain airplane configurations
Max airspeed with landing gear extended?
250KIAS/0.7 M
Max operating airspeed for extending/retracting landing gear?
200KIAS
Which single HYD SYS for all aspects of nose gear operations?
HYD SYS 3
HYD SYS(s) that operates the normal landing gear extension/retraction?
HYD SYS 2 and 3
How is excessive air pressure due to heat buildup in main wheel/tire assembly released?
Four heat sensitive fuse plugs
How are main gear inboard doors normally operated?
HYD SYS 3
Recommended actions to nose gear for all towing operations?
Disconnect the nose wheel steering torque links
What conditions cause the auto brake to disarm?
Brake pedal application >20%, autobrake switch selected off, autobrake or BCU system fault, wheel speed invalid, ground spoilers stowed after being deployed
How is NWS controlled and actuated?
Electrically controlled and hydraulically actuated?
How is NWS steering operated after manual gear extension?
Free caster mode
How are the brakes controlled and actuated?
Electrically controlled and hydraulically actuated
How is weight on wheels(WOW) sensing accomplished?
Two proximity sensors on each main and nose gear assembly
Max operating altitude with landing gear extended?
20,000ft
How is main landing gear overheat detected?
Single loop heat sensing elements
Which HYD SYS operates the braking system?
HYD SYS 2(outboard brakes), HYD SYS 3(inboard and parking/emer brake system)
The 3 conditions where gear warning horn is not mutable?
When activated by flap position, both throttles idle, radio altimeter(s) valid
What are the two operating modes of the gear warning horn system?
Primary(operable rad alt) and secondary(below 16,500ft and no serviceable rad alt)
How is BRAKE OVHT warning message removed from EICAS if the condition no longer exists?
Momentarily pressing the BTMS OVHT WARN RESET
How is normal extension and retraction of the landing gear controlled?
Electrically controlled by the landing gear electronic control unit (LGECU)
After manual landing gear extension, which gear door caution messages remain displayed?
L-R MAIN GEAR DOOR, NOSE DOOR
How is the park/emergency brake actuated?
Mechanical linkages transfer manual inputs from the parking brake lever to the parking brake valve
Autobrake at LOW, MED or HI, what two conditions must be met to activate the auto brake system?
Both MLG indicate WOW for >5 secs or wheel spin up >50 KIAS and the ground spoilers are commanded to deploy
What type of brakes are used on the Global Express aircraft?
Carbon disc brakes
What is the sequence of events that occur during manual landing gear extension?
Mechanical release of all LG unlocks and gear doors. SYS 3 shutoff valves block HYD pressure operating the gear uplocks and doors, dump valve opens transferring SYS3 pressure from gear and doors to return. SYS2 pressure assists in main door downlock
What is meant by the term brake by wire?
Rudder pedal braking input is converted to an electrical signal (transducers) and sent to the brake control unit (BCU)
