Landing Gear Flashcards
Describe the ‘OFF’ position of the landing gear (747-400)
Landing gear hydraulic system is depressurized.
How many degrees can the nose wheel steering system turn the nose wheel with the tiller? With the rudder pedals?
Tiller = 70 degrees
Rudder Pedals = 7 degrees
What does the ‘BRAKE SOURCE’ light indicate?
Low pressure in active brake sources (HYD SYS 4, 1, 2).
How is the landing gear held in position after retraction?
Main gear held in position by uplocks,
Nose Gear mechanically held in the up position.
When does RTO apply maximum braking? (3 Items)
Airplane on Ground,
Wheel speed above 85 kts, and
Thrust levers at Idle.
What is the purposed of the brake accumulator?
Provides pressure for parking brake.
What does a white crosshatched expanded gear position mean?
Associated gear is in transit.
What conditions must be satisfied for the landing gear lever lock to be released? (2 Items)
Wing Gear tilted, and
Body Gear centered
What hydraulic system pressurizes the brake accumulator?
HYD SYS 4.
What BTMS value causes the ‘BRAKE TEMP’ EICAS to appear?
5 or higher.
How does the landing gear extend with the alternate gear extension system?
Gear uplocks and doors are electrically unlocked, and gear free falls into position.
Why is it necessary to pressurize HYD SYS 4 before the other systems?
Precludes the transfer of fluid from HYD SYS 1 and 2 into HYD SYS 4. When the parking brake is set and released, brake return lines dump into system 4.
What does an EICAS ‘LIMITER’ message indicate? (3 Items)
Limiter failure on more than 1 wheel per truck,
Parking brake lever is released, and brake valve is not fully open, or
Brake system control unit power loss occurs.
What does an EICAS ‘LIMITER’ message indicate? (3 Items)
Limiter failure on more than 1 wheel per truck,
Parking brake lever is released, and brake valve is not fully open, or
Brake system control unit power loss occurs.
