Systems: Landing Gear and Brakes Flashcards
What is the nosewheel turning range with rudder pedals alone? With handwheel and nosewheel?
Nosewheel only 5 degrees
Nosewheel and hand steering 76 degrees
Do you need a fully operational nosewheel steering system in order to steer the aircraft with the rudder pedals?
No, although in the event the steering system has been disengaged, turning ability through the rudder pedals along is a function of rudder authority (airspeed).
How does the landing gear operate?
The gear is electronically commanded, hydraulically actuated and mechanically locked. When the landing gear lever is placed to the UP or DOWN position, a signal is transmitted to the Landing Gear Electronic Unit (LGEU) which allows hydraulic fluid to extend or retract the gear.
What is the minimum parking brake pressure?
Although parking brake pressure is not monitored directly by the pilots, a caution message, EMERG BRK LO PRES, is displayed on the EICAS in case of low pressure inside the #2 accumulator.
If the EICAS message is present upon powering up, testing the hydraulic system per Setup Check procedures should re-charge the #2 accumulator restore proper pressure to the system.
How does the electrical override extension work?
The LGEU is bypassed and directly actuates the landing gear electro valve and nose gear doors solenoid valve. The DOORS function opens the nose landing gear doors. The GEAR/DOORS function extends the gear.
How does the free-fall extension work?
If the normal and electrical override switch do not work, pull the free fall lever UP. This actuates the free-fall selector and unlocks the gear so that it can fall by gravity.
Can the gear be pumped up?
No
When do you get a gear warning annunciation?
RA below 1200, low thrust lever angle
RA below 1200, flaps 22 and 45 and low thrust lever angle
Flaps lever 45
In the event of an RA failure, gear warning will activate at any altitude with low thrust setting but may be canceled by pressing the landing gear warning cutout button.
What are the weight on wheels sensors and what is their purpose?
5 weight on wheels proximity switches, 2 on each main and one on the nose, relay shock-absorber compression information.
When does the anti-skid system ha e to be operative?
Anti-skid must be functional during a LAHSO.
