Landing Gear Flashcards
What conditions are required that will cause the green towing light on the nose gear to illuminated?
Parking brake off
Nosewheel steering disengaged
Toe brakes not applied
What does the red guarded steering switch on the forward ramp panel do?
Disengage nosewheel steering
Enables re-engagement of nosewheel steering
How can you tell if the rampers left the steering disconnect switch on the ground service panel not in the down and guarded position?
During the after start check, the captain presses the tiller. If the STEER OFF EICAS extinguishes, the ramper’s switch is down and guarded.
What indications do you need to be safe for pushback?
Green towing light on the nose gear
Parking break ON light extinguished
STEER OFF EICAS displayed
Which hydraulic system controls nosewheel steering?
HYD SYS 2
The nosewheel steering system is a(n) _______ controlled and ________ actuated brake by wire system.
Electronically, hydraulically
For high speed steering on the ground, which steering mode is used?
Rudder pedal steering mode
How do you engage the nosewheel steering system?
The steering handle must be pushed down
How is nosewheel steering angle limit affected by wheelspeed?
Steering angle limit decreases as speed increases
What disengages rudder pedal steering?
The activation of nosewheel steering
When do you use hand steering mode?
Low speed control or sharper turn angle required
What is the turn radius for a 180 degree turn in the E170?
54 feet 8 inches
What is the turn radius for a 180 degree turn in the E175?
59 feet 2 inches
During taxi out, ATC asks you if you can hold in the holding bay for runway 18. There is a note on the plate: “Holding bay at Rwy 18 closed except aircraft with wingspan less than 79.’”
No
What determines the minimum turn radius obstruction clearance path for an aircraft with standard winglets?
Horizontal stabilizer tip
What determines the minimum turn radius obstruction clearance path for an aircraft with enhanced wingtips?
Enhanced wingtip
The main landing gear is held up and locked in position by:
A mechanical uplock
In what 2 situations can the landing gear warning not be silenced?
SLAT/FLAP lever in the 0,1,2,3, or 4 with
- RA below 700 ft AGL and
- Thrust lever is set below a predetermined mid-range position
OR
SLAT/FLAP lever in a landing position (5 or FULL) regardless of thrust lever position or radio altitude
What keeps the gear down and locked?
Downlock springs
What color is the in transit indication for landing gear on the EICAS?
Amber
What color is the up and locked indication for the landing gear?
White
What color is the down and locked indication for the landing gear on EICAS?
Green
What color is the gear position and lever disagreement indication on the EICAS?
Red (20 second grace period)
What does a red icon indicate on the landing gear position indicator?
A discrepancy between the landing gear lever position and the respective landing gear position
OR
Landing gear kept in transit and is not locked in the commanded position
How do the landing gear doors actuate?
Mechanically, during landing gear extension or retraction
How is the landing gear extended or retracted?
Electrically commanded, hydraulically activated
What are the three landing gear extension modes?
Normal, electrical override, and alternate gear extension
When would you use the alternate gear extension procedure?
If hydraulic pressure is not available for gear operation or the electrical system fails
Describe the use of the alternate gear extension lever.
Relieves hydraulic pressure in the lines and releases all uplocks, gear extends by freefall (gear must be down to get 3 green on EICAS)
Describe the normal landing gear extension procedure
Landing gear lever down releases the hydraulic pressure for the uplocks and retraction actuators
When would you use the electrical override switch (extension)?
When the landing gear lever control box fails, bypassing the Proximity Sensor Electronics Module (PSEM) and commands gear extension in the same sequence as normal
When is the LG WRN INHIB switch used?
To inhibit the landing gear warning in the event of a dual radio altimeter failure
Can the landing gear aural warning be silenced by pushing the LG WRN INHIB button?
Only if both radio altimeters have failed and flaps are set 0-4
What is the purpose of the DN LOCK RLS button on the landing gear lever?
a. Manually releases the landing gear lever lock if gear won’t retract on takeoff and terrain is imminent
b. Lock protects against inadvertent landing gear retraction with weight on wheels
Hydraulic systems _____ power the brakes.
1 and 2
What hydraulic systems provide brake pressure?
HYD 1: Outboard brakes, emergency brake
HYD 2: Inboard brakes, emergency brake
The LANDING and RTO modes will be disarmed if any of the following conditions occur:
- Toe brakes actuated
- Auto brakes set to OFF
- Brake Control System is failed
- Thrust lever is advanced beyond idle during autobrake application
How many full brake applications will the parking/emergency brake accumulator provide?
6 full applications
How do you know the parking brake is set?
An ON light illuminates on the EMER/PKNG BRAKE light
Can the parking brake be used to stop the aircraft if you lose hydraulic systems 1 and 2?
Yes
What conditions must be met for the autobrakes to engage during a rejected takeoff?
Thrust levers IDLE or REV
Wheelspeed above 60 knots
Brake pedals not pressed
How are the brakes commanded?
Brake by wire, electrically commanded and hydraulically activated
Pedal position transducers send brake requests to the BCM (Brake Control Module)
If the brake indicator pins are flush, are brakes within acceptable limits?
Yes
When does touchdown protection deactivate for braking?
3 seconds after weight on wheels has sensed ground, or >50kt wheelspeed
_______ prevents tire skidding and ensures maximum braking efficiency.
Anti skid protection
There is anti-skid protection when using the emergency brake (T/F).
False
What does anti-skid provide?
When does it deactivate?
Reduces wheel brake pressure in order to recover wheelspeed and prevent tire skidding (deactivates <10 knots).
When is the anti-skid system deactivated?
Below 10 knots
What does Locked Wheel provide?
If a wheelspeed is 33% or below its paired wheel’s speed, the BCM commands zero pressure to the brake of the slower wheel, allowing speed equalization (deactivates below 30 knots).
When is Locked Wheel Protection deactivated?
Below 30 knots
Taking off with AMBER brake temperature indications is allowed (T/F).
False
Activation of the DN LOCK RLS button is prohibited for all takeoffs unless what?
Unless required for obstacle clearance.
What is the maximum gear extension speed?
250 knots
What is the maximum gear retraction speed?
250 knots
What is the maximum gear extended speed?
250 knots
What is the maximum tire ground speed?
195 knots
What is the memory item for STEERING RUNAWAY?
STEERING DISC SWITCH…… PRESS
What do PSEMs do?
Proximity Sensor Electronic Modules sense weight on wheels using six sensors, two on each landing gear.
When does the PSEM prevent gear retraction?
If two WOW sensors on the same gear are failed or
If the shock absorber fails to extend completely, the PSEM will continue to compute a WOW signal of on ground
Describe the normal landing gear retraction sequence.
Hydraulic pressure is released for the nose and main landing gear locks
The respective actuators pressurize to retract the gear
The gear indications change in the EICAS to show it is in transit
