Landing Gear Flashcards
What are the type of struts?
Air/Oil
What does the torque knee do on the nose wheel?
Transmits steering motions and nose wheel shimmy damping
How are the landing gear doors moved?
Mechanical actions
How is the nose gear doors attached?
Via hinges and are spring loaded to open position.
How do the nose gear doors retract?
Roller on each side of the assembly engages a cam assembly on each door and draws the doors closed behind the gear
How are the main gear doors attached?
Hinged on the sides and connected to an actuator torque-tube assembly with 2 push pull links
How is the landing gear controlled?
Electrically controlled, hydraulically actuated
How is the landing gear held in a down position? Up position?
Folding braces called “drag legs,” mechanical downlocks.
Held up by hydraulic pressure
How is hydraulic power supplied to the system?
A hydraulic power pack
What controls the flow of hydraulic fluid to individual gear actuators?
Electrically actuated selector valve - which receives power from the landing gear control switch
How is the gear extended and retracted?
Via a hydraulic power pack
There are 3 hydraulic lines which run from the power pack - what are they for?
Normal extension, retraction, and emergency extension which is all routed to the nose and main gear actuators
Where are the normal and manual extension lines connected to the hydraulic actuator at?
Upper end
How long will the pump motor run?
Until all three landing gears are down and locked
At what PSI does the nose gear actuator unlock at?
200-400 PSI of hydraulic pressure
When the hydraulic pressure reaches _____, the uplock pressure switch will cause the landing gear relay to open and interrupt the current to the pump motor
1,850 PSI
What happens if the hydraulic pressure drops to 1,600 PSI?
The pressure switch will cause the pump to actuate
What mechanism do the squat switches control?
Down lock hooks
When do the downlock hooks unlock?
When the plane leaves the ground
What does the red light in the gear handle mean?
The gear is in transit or in an unsafe position
What’s the purpose of up limit switches?
To actuate when the gear is fully up to allow the system to know that it is actually up
What does the down limit switch also function as?
A warning system
When will the landing gear in transit light illuminate?
Landing gear handle in up position and airplane is on the ground
Flaps up or approach and one or both power levers retarded below 79 +- 2% N1, one or more landing gears are not down and locked
Any landing not in fully retracted position
Flaps are beyond the approach position (36% or more) with any gear not down, regardless of power lever position
Name the different scenarios when the landing gear warning horn will go off
Gear up, flaps up, power -77% to +81% (silence by button)
Gear up, flaps approach, -77% to +81% (silence by button)
Gear up, flaps past approach, any power setting (silence by lowering gear)
What’s the process for letting the gear down manually?
Pulling landing gear relay circuit breaker, put landing gear control in the down position, remove pump handle from securing clip, pump the handle down until the green gear lights illuminate and resistance is felt
What are the type of brakes?
A non-assisted hydraulic brake system
What’s the main gear brakes equipped with?
Multi-disc hydraulic brakes
