Landing Gear Flashcards
Which hydraulic systems must be powered when checking the brake wear indicators?
System 2 and 3 and the brakes must be applied
Which hydraulic system powers the landing gear?
System 3.
Which hydraulic systems can be used to assist manual landing gear extension if the main system fails?
System 2.
What effect will the loss of both the #2 and #3 hydraulic system have on the landing gear?
You will not be able to lower the nosegear—no pressure available to force it off the uplock.
In the event of a #2 and #3 hydraulic system failure, what emergency braking is available?
Brake accumulators in both systems should provide reserve pressure for six applications with the anti skid OFF.
How is the Anti-Skid test performed?
The Anti-Skid Control Unit is equipped with a self test feature. It is also tested during the originating check by cycling the Anti-Skid switch.
What should you do if you are unable to raise the gear handle after takeoff?
Use the DN LCK REL button next to the gear handle to release the downlock mechanism
What effect will the loss of either the #2 or #3 hydraulic system have on braking capability?
Anti-skid braking will be available from the remaining system, with a 50% loss of stopping capability.
Locked wheel protection is provided by the anti-skid system upon landing. When will the system allow braking to occur?
Wheel spin up speed reaches 35 kts or 5 seconds after WOW signal is present.
When the parking brake is set and hydraulic systems are deactivated, what effect does it have?
Pressure will bleed off in the #2 system but will be maintained from the #3 system brake accumulators because of a parking brake shutoff valve.
After an overheated brake is cooled in flight by lowering the gear, how can the pilot reset the BTMS indicating system?
Press the BTMS OVHT WARN RESET button on the landing gear panel.
With the same indications of an overheated brake on the ground, what should you do?
Do not reset the BTMS system until maintenance has had a chance to inspect the brake.
The nosewheel steering system allows travel of _______ from neutral with the rudder pedals and ______ with the handwheel control unit.
8 degrees/80 degrees
With a failure of the nosewheel steering system, the nosewheel will go into the ____________.
Free castering mode
Bumping or moving the nosewheel tiller after landing gear extension will interfere with a system test and cause the nosewheel steering to be: ____________.
Inoperative upon landing, with no advance warning to the pilot in flight
How does the parking brake work?
The parking brake shutoff valve is used to lock the brakes on by trapping hydraulic system 3 pressure. When the hydraulic system is shutdown system 3 accumulator pressure should keep the brake applied for an extended period of time
How are the tires thermally protected from blowout?
through the use of four thermal fuse plugs in each wheel
What are the brake accumulators charged to
750psi
How many brake applications are available from an accumulator charge?
up to 6
Can braking be accomplished through the use of accumulator pressure?
yes
Where is the brake energy chart found?
QRH1
What is the minimum turn around time after a landing or rejected takeoff?
15 minutes to insure max brake temperature
What is touchdown protection?
Guards from inadvertent landing with the brakes applied if the pilot is pressing the brake pedals. Braking will not be applied until a wheel spin up to 35 knots is achieved, or weight on wheels plus 5 seconds
What is locked wheel protection?
The anti skid control unit (ASCU) monitors each wheel to ensure even rotation. If one wheel enters a skid and is at least 30 percent slower than the others, the ASCU will release brake pressure to that wheel to balance the rotation speeds
What holds the MLG in the extended position?
Mechanical over centering with down locks
What holds the nose gear in the retracted position?
A spring loaded over-center type locking mechanism
What holds the main gear in the retracted position?
Mechanical up locks and hydraulic system 3 pressure
What controls the landing gear?
The Proximity Sensing Electronic Unit PSEU
what position are the nose gear doors in the down gear position?
The doors are open
What ensures the nose wheel is centered prior to reaction into the wall?
the ECU sends a signal to center after takeoff, then a centering cam keeps it centered when hydraulic pressure is removed.
When will the “TOO LOW GEAR” aural warning sound?
with radar altitude below 500 feet at a speed of less than 190 KIAS
why is it important not to move the tiller in flight with the gear extended?
The steering will be inoperative as annunciated by a STEER INOP message on EICAS upon landing however you will have no warning in flight.
