Landing Gear and Brakes Flashcards
Describe the OFF position of the landing gear.
• Landing gear hydraulic system is depressurized.
Note: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 pedals
Note:FCOM, VOL 2; 14.10.2, and 14.10.3
When does RTO apply maximum brake pressure?
- Airplane on the ground
- All 4 thrust levers are closed, and
- Above 85 knots.
Note:FCOM, VOL 2; 14.10.4; 14.20.4
What does the BRAKE SOURCE amber light indicate when illuminated?
• Active brake hydraulic sources (hydraulic systems 4, 1, and 2) have low pressure
Note:FCOM, VOL 2; 14.10.5
What does a white, crosshatched, expanded gear position indication mean?
• Respective landing gear in transit
Note:FCOM, VOL 2; 14.10.7
What does an amber X display on an expanded gear position mean?
• Landing gear position indicator inoperative
Note:FCOM, VOL 2; 14.10.7
What does a white empty box on the Gear synoptic display indicate?
• Respective landing gear door position indicators inoperative
Note:FCOM VOL 2; 14.10.8
What sensing systems control in flight and ground operation of various airplane systems?
- Air/ground sensing system
- Nose gear extension sensing system
Note:FCOM, VOL 2; 14.20.1
How does the airplane distinguish between air mode and ground mode?
• A combination of main gear tilt sensors
Note:FCOM, VOL 2; 14.20.1
Nose gear extension sensing provides a signal to relays controlling functions
in which systems?
- Stall warning
- Nose gear steering
Note:FCOM, 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 centered
Note:FCOM, VOL 2; 14.20.1
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 indications
Note:FCOM, 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.
Note:FCOM, VOL 2; 14.20.2
During landing gear extension, state what happens if any gear position disagrees with lever position after normal transit time.
• The EICAS changes to the expanded non-normal format
• Affected gear displayed as in transit, or UP if the gear never unlocked
from the up position.
Note:FCOM, VOL 2; 14.20.2
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
- Springs pull the downlocks into the locked position
Note:FCOM VOL 2; 14.20.2
When does body gear steering operate?
• When the nose wheel steering angle exceeds 20 degrees
Note:FCOM, VOL 2; 14.20.3
When is body gear steering activated and when is it deactivated?
- Ground speed decreasing through 15 knots
- Ground speed increasing through 20 knots
Note:FCOM, VOL 2; 14.20.3
What is the purpose of the brake accumulator?
• Provides parking brake application
Note:FCOM, VOL 2; 14.20.3
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
Note: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 sent to alternate anti-skid valve.
- Brake pressure is released on a laterally paired wheel basis.
Note:FCOM, VOL 2; 14.20.4
When do the auto brakes apply after landing?
- All thrust levers are closed
- Ground mode sensed
- The wheels have spun up
Note:FCOM, VOL 2; 14.20.5
Which systems contribute to total airplane deceleration on landing and reduces autobrake pressure?
- Thrust reverse
- Spoilers
Note:FCOM, VOL 2; 14.20.4
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
• Loss of normal hydraulic pressure
Note:FCOM, VOL 2; 14.20.5
What hydraulic system pressurizes the brake accumulator?
• System 4
Note:FCOM VOL 2; 14.20.5
Can the airplane be stopped with normal accumulator pressure?
• No, the accumulator is not designed to stop the aircraft.
Note:FCOM, VOL 2; 14.20.5
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.
Note:FCOM, VOL 2; 14.20.6
What provides automatic brake source selection?
• Pressure-operated selector valves
Note:FCOM, VOL 2; 14.20.1
What value on the brake temperature monitoring system causes the BRAKE TEMP Advisory EICAS message to appear?
• 5
Note:FCOM, VOL 2; 14.30.2
What does it mean when the Brake Source light is illuminated on the Captain’s panel?
Active brake source (Hydraulic systems 4, 1 and 2) have low pressure
What is the difference between the normal and alternate brake systems?
Normal system operates off hydraulic system 4. Autobrakes and full anti-skid is available. The alternate system operates off hydraulic system 1(if 4 fails) then 2 (if 1 fails). Anti-skid is reduced to pairs of wheels and autobrakes are not available.
Can I select autobrakes when hydraulic system 1 is the active brake source?
No
Above what ground speed does the RTO function become available?
85 knots