LANDING GEAR AND BRAKES Flashcards
Describe the OFF position of the landing gear?
• Landing gear hydraulic system is depressurized.
FCOM, VOL 2; 14.10.1
How many degrees can the nose-wheel steering system turn the nose gear with the tiller, and how many degrees with the rudder pedals?
- 70 degrees in either direction with the tiller
- 7 degrees with the rudder pedalsFCOM, VOL 2; 14.10.2/3
When does RTO apply maximum brake pressure?
- All 4 thrust levers are retarded to idle, and
- Groundspeed above 85 knots.FCOM, VOL 2; 14.10.4; 14.20.5
What does the BRAKE SOURCE amber light indicate when illuminated?
• Active brake hydraulic sources (systems 4, 1, and 2)
have low pressure
FCOM, VOL 2; 14.10.5
What does a white, crosshatched, expanded gear position indication mean?
• Respective landing gear in transit.
FCOM, VOL 2; 14.10.7
What does an amber X display on an expanded gear position mean?
• Landing gear position indicator inoperative.
FCOM VOL 2 14.10.7
What does a white empty box on the Gear synoptic display indicate?
• Related landing gear door position indicators inoperative.
FCOM VOL 2; 14.10.6
What sensing systems control in flight and ground operation of various airplane systems?
• Air/ground sensing system, main gear tilt sensors provide air/ground
signal to relays which control various systems.
• Nose gear extension sensing system provides signals to relays controlling
functions in the stall warning and nose gear steering systems.
FCOM, VOL 2; 14.20.1
How does the airplane distinguish between air mode and ground mode?
• A combination of main gear tilt sensors indicate the main gear are tilted
(Air mode), or not tilted.(ground mode)
FCOM, VOL 2; 14.20.1
Nose gear extension sensing provides a signal to relays controlling functions in which systems?
- Stall warning
- Nose gear steeringFCOM, VOL 2; 14.20.1
What conditions must be satisfied in order for the landing gear lever lock to release?
- Main gear are tilted
- Body gear centred.FCOM, VOL 2; 14.20.2
Describe the sequence of events when the landing gear lever is moved UP?
- The landing gear doors open
- Automatic braking occurs
- Landing gear begin to retract.
- EICAS gives related indicationsFCOM, VOL 2; 14.20.2
How are the landing gear held in position after retraction?
- Main gear are held in the up position by uplocks
- The nose gear is mechanically locked in the up position.FCOM, VOL 2; 14.20.2
During landing gear extension or retraction, state what happens if any gear position disagrees with lever position after normal transit time.
• The EICAS changes to the expanded non-normal format,
• GEAR DISAGREE master caution with beeper.
• Affected gear displayed as in transit, or UP/DOWN if the gear never
unlocked from the UP/DOWN position.
FCOM, VOL 2; 14.20.2/3
How does the gear extend through the alternate gear extension system?
- By pushing the alternate gear extend switches
- The gear uplocks and gear door latches are electrically released.
- The gear free-falls
- Gravity and air loads extend the gear, and
- Springs pull the downlocks into the locked positionFCOM VOL 2; 14.20.3
When does body gear steering operate?
• When the nose wheel steering angle exceeds 20 degrees
• Ground speed is less than 15 knots.
• As speed increase’s through 20kts on take off, the body gear is hydraulically
centred, and body gear steering is deactivated.
FCOM, VOL 2; 14.20.3
When is body gear steering deactivated?
• Ground speed increasing through 20 knots
FCOM, VOL 2; 14.20.3
What is the purpose of the brake accumulator?
• Provides parking brake application
FCOM, VOL 2; 14.20.4
Describe the difference between normal and alternate anti-skid braking systems?
• Normal brake antiskid provides each main gear wheel with
individual antiskid protection.
• Alternate brake antiskid provides antiskid protection to lateral
wheel pairs (forward and/or aft pair on each truck),
rather than to individual wheels
FCOM, VOL 2; 14.20.4
How does the brake torque limiter function in the Alternate brake system?
- Brake torque is sensed on an individual wheel basis.
- signal is sent to the alternate anti-skid valve, and
- Brake pressure is released on a laterally paired wheel basis.FCOM, VOL 2; 14.20.5
When do the auto brakes apply after landing?
- All thrust levers are closed,
- Ground mode sensed, and
- The wheels have spun up.FCOM, VOL 2; 14.20.5
Which systems contribute to total airplane deceleration on landing?
- Autobrakes
- Thrust reverse
- SpoilersFCOM, VOL 2; 14.20.5
Give examples of what would disarm the autobrakes after landing?
• Pedal braking applied,
• Any thrust lever advanced after landing,
• Speedbrake lever moved to DOWN detent after speedbrakes
have been deployed on the ground,
• DISARM or OFF position selected on the autobrakes selector,
• Autobrake fault,
• Normal antiskid system fault, and
• loss of normal brake hydraulic pressure.
FCOM, VOL 2; 14.20.6
What hydraulic system pressurizes the brake accumulator?
• System 4
FCOM VOL 2; 14.20.6
Can the airplane be stopped with normal accumulator pressure?
• No, the accumulator is not designed to stop the aircraft.
FCOM, VOL 2; 14.20.6
Why is it necessary to pressurize hydraulic system 4 before pressurizing the other systems?
• Precludes the transfer of hydraulic fluid from system 1 or 2 into system 4,
when the parking brake is set, and then released.
FCOM, VOL 2; 14.20.6
What provides automatic brake source selection?
• Pressure-operated selector valves.
FCOM, VOL 2; 14.20.1
What value on the brake temperature monitoring system causes the BRAKE TEMP Advisory EICAS message to appear?
• 5
FCOM, VOL 2; 14.30.1 (bottom)
