Landing Gear & Brakes Flashcards
Landing Gear Description
- How is it controlled, by what system, and what are its backups
- Landing gear warning tone sounds whenever the gear is not down and locked and any of the following conditions exist: (2)
• Electrically Controlled
• Hydraulically Actuated
• #2 Hydraulic System is the normal source of power
• PTU supplies back-up hydraulic power to the #2 Hydraulic System
• An Alternate Landing Gear Extension system provides an alternate means of manually extending the landing gear
• Landing gear warning tone sounds whenever the gear is not down and locked and any of the following conditions exist:
o Flaps are greater than 8.5° with either engine torque indicating less than 50% and both power levers positioned aft of the RATING detent
o Airspeed is less than 156 KIAS with both power levers near the FLIGHT IDLE detent
Main Landing Gear
- Extension and retraction direction
- Doors are identified as ___ and work how
- How many gear pins
- How many brake wear indicators
- Extends forward
- Retracts aft
- Equipped with a door assembly consisting of a pair of forward doors and a pair of aft doors
- Forward doors are mechanically linked to the main strut
- Aft doors are hydraulically sequenced automatically during gear operation
- When gear is retracted all doors are closed
- 5 “Pins” total: 1 for the main gear and 1 for the main door (2 pins per side) & 1 for the nosewheel door
- 8 “Break Wear Indicators” total: 4 on each main landing gear (2 forward & 2 aft)
Nose Gear
- Extension and retraction direction
- Doors are identified as ___ and work how
- Nose wheel is equipped with an ___
- Extends aft
- Retracts forward
- Equipped with a door assembly consisting of a pair of aft doors and a pair of forward doors
- Aft doors are mechanically linked to the nose gear strut (When the nose gear is down, the aft doors remain open)
- Forward doors are hydraulically sequenced automatically during gear operation
- Nose gear is equipped with an integral ground lock mechanism (manually operated using a spring-loaded panel on the left side of the nose)
Brake System
- Powered by
- When does Anti-Skid activate
- How many seconds until activation of Anti-Skid if on slippery runway
- Min speed for Anti-Skid operation
• Powered by the #1 Hydraulic System
• Anti-Skid Equipped
o Anti-Skid activates when the main brake system receives a WOW signal and senses a main wheel speed of 35 knots
o In conditions of low runway friction (i.e. ice) where the main wheel spin up may be delayed, the control unit will reactivate main brake capability 5 seconds after receiving WOW signal
• Minimum speed for Anti-Skid operation is 10 knots
Emergency Brake System
• Powered by #_ Hydraulic System
• Used for ___
• Alternate means of ___
• Accumulator in the system maintains hydraulic pressure to the parking brake after ___
• Accumulator provides approx _ applications of emergency braking if both the #1 and #2 Hydraulic Systems fail
• A manually operated hand pump, located in right main wheel well, is used to ___
• An Emergency/Parking brake accumulator pressure gauge is located in the ___ and can be used to confirm increasing pressure when performing this procedure
• An addition “Gear Pump Handle” is located inside the ___
NOTE: Minimum indicated parking brake pressure prior to starting the RIGHT engine first is ___ psi
NOTE: Minimum indicated parking brake pressure prior to starting the LEFT engine first is ___ psi
- Powered by #2 Hydraulic System
- Used for setting the parking brake
- Alternate means of main brake application if the normal brake system should fail
- Accumulator in the system maintains hydraulic pressure to the parking brake after engine shutdown
- Accumulator provides approx 6 applications of emergency braking if both the #1 and #2 Hydraulic Systems fail
- A manually operated hand pump, located in right main wheel well, is used to restore Emergency/Parking brake accumulator pressure when necessary
- An Emergency/Parking brake accumulator pressure gauge is located in the right wing root area and can be used to confirm increasing pressure when performing this procedure
- An addition “Gear Pump Handle” is located inside the RIGHT main landing gear wheelwell
NOTE: Minimum indicated parking brake pressure prior to starting the RIGHT engine first is 500 psi
NOTE: Minimum indicated parking brake pressure prior to starting the LEFT engine first is 1000 psi
Nosewheel Steering System
• Powered by the #_ Hydraulic System
• Steering Hand Control turns the nosewheel up to __° either side of center for low speed taxi
• Rudder pedals turns the nosewheel up to _° either side of center for high-speed taxi, take-off and landing roll
• Nosewheel steering system will revert to free castoring mode whenever any of the following conditions exist: (4)
• In the free-castor mode, the nosewheel will rotate up to ___° either side of center
• When operating free castoring mode, ___ must be used for directional control
NOTE: Nosewheel steering must always be selected ___ for all towing and push back operations
• Powered by the #2 Hydraulic System
• Steering Hand Control turns the nosewheel up to 70° either side of center for low speed taxi
• Rudder pedals turns the nosewheel up to 8° either side of center for high-speed taxi, take-off and landing roll
• Nosewheel steering system will revert to free castoring mode whenever any of the following conditions exist:
o Nosewheel angle exceeds 70° left or right of center position
o Steering Control Unit (SCU) fails
o STEERING switch is selected to the OFF position
o Following an alternate gear extension
• In the free-castor mode, the nosewheel will rotate up to 120° either side of center
• When operating free castoring mode, differential braking and/or differential power must be used for directional control
NOTE: Nosewheel steering must always be selected OFF for all towing and push back operations
Alternate Landing Gear Extension
• System provides a manual means of extending the landing gear when any of the following malfunctions occur: (3)
• System provides a manual means of extending the landing gear when any of the following malfunctions occur:
o “LDG GEAR INOP” Caution light is illuminated or,
o Landing Gear indication fails or,
o Loss of #2 Hydraulic System fluid
Alternate Landing Gear Release/Extension Doors (CEILING & FLOOR)
• “LANDING GEAR ALTERNATE RELEASE”
- Location of handle
- What happens when the door is opened
- What happens when the bypass valve is opened
• Opening this door also allows access to the “MAIN L/G RELEASE” Handle:
- This is used to
• “LANDING GEAR ALTERNATE RELEASE”
o Located in the flight deck CEILING (over the F/O’s seat)
o Opening this door mechanically operates (opens) a bypass valve in the normal gear extension system
o Opening of the bypass valve relieves #2 Hydraulic System pressure from the landing gear uplocks to allow for a manual release of the landing gear
• Opening this door also allows access to the “MAIN L/G RELEASE” Handle:
o “MAIN L/G RELEASE” handle is pulled to release the main landing gear doors and main gear uplocks
o Main gear will free fall into the down position but may require to be pumped down to obtain full down and locked position
Alternate Landing Gear Release/Extension Doors (CEILING & FLOOR)
• “LANDING GEAR ALTERNATE EXTENSION”
- Location and what is found in there
- What happens when door is opened
• “LANDING GEAR ALTERNATE EXTENSION”
o Located on the flight deck FLOOR. Opening of this door gives access to:
“NOSE L/G RELEASE” handle
Alternate extension hand pump
“Alternate Downlock Verification” Light System
• Opening this door mechanically operates (opens) the MLG alternate selector valve
• Opening this valve is necessary for pump operation
o Insert the pump handle into the socket and pump to assure complete main gear extension and downlock
Alternate Landing Gear Release/Extension Doors (CEILING & FLOOR)
• “LANDING GEAR ALTERNATE EXTENSION”
• “NOSE L/G RELEASE” handle is pulled to ___
- How does the gear reach the down and locked position
- Will the normal landing gear advisory lights indicate along with the alternate in the floor
• “NOSE L/G RELEASE” handle is pulled to release the nose gear doors and nose gear
o Nose gear will free fall aft to a full down and locked position, being assisted by airflow
o Advisory lights on the landing gear control panel will indicate the status of all gear doors and gear
o “Alternate Downlock Verification” light system (in the floor) provides a redundant means of verifying the down and locked status of the landing gear
Landing Gear INHIBIT Switch
- Location
- What does it do
- Why
- Switch is located in the flight deck CEILING (over the F/O’s seat) adjacent to the “LANDING GEAR ALTERNATE RELEASE” door
- Selecting switch to “INHIBIT” disables the electrical command sent to the gear solenoid valve for normal extension when the landing gear select handle is moved
- Landing gear select handle can then be moved without gear activation
