Wheels And Tyres Flashcards
Do the main wheels have an overpress plug
An inflation valve and an overinflation plug are installed in the inner wheel assembly, 180 degrees apart. The overpressure-relief plug is a stainless steel rupture disc, which releases pressure in a controlled manner in the event of an overpressurization (325 psi).
4 off
Is there a heat transfer plate
A one-piece heat shield is installed in the inner wheel half to reduce heat transfer from the brake unit. Four thermal relief plugs, located in four of the eight drive lugs in the inner wheel half, provide overheat protection (release at 200°C (390°F)). Eight stainless steel inserts are attached to the drive lugs by screws and engage drive slots in the brake rotor disks.
What is normal brake syst press
1400 to 3200
What is min press for park brake
1100psi
What are brake position transducers
4 brake position transducers
Brake Pedal Position Transducers Figure H2 The brake pedal position transducers are dual linear variable differential transformers (LVDTs). They are used to convert mechanical movement of the brake pedals to electrical signals for each BCU. The signals from the four pedal LVDTs correspond to hydraulic brake pressure commands. Each LVDT (dual electric and single mechanical drive) provides two independent channels of electrical signals that control the main brakes in symmetrical pairs: inboard brakes and outboard brakes. One coil of each LVDT is connected to channel A, with the other coil connecting to channel B. A dead band is provided in the LVDT stroke to preclude inadvertent brake operation during rudder pedal operation. The pedal LVDTs have a built-in feel spring to provide brake pedal feel forces. To provide redundant brake pedal return capability, external pedal return springs are installed in each brake pedal mechanism.
How many brake channels
2= A and B
What does the shutoff valve do
Shutoff Valves
Figures H4 and H5
A solenoid operated three-way shutoff valve is located downstream of the pressure switch in the brake system no. 2, and downstream of the pressure transducer in the system no. 3. The shutoff valves isolate the brake control valves from system hydraulic pressure during flight, while releasing brake pressure back to return. The shutoff valves also serve to remove hydraulic pressure from the brake control valves when uncommanded brake application is detected. The valves are energized open with either of the 28-V dual power supplies, allowing pressure to the brake control valves. The 28 V is supplied from each card, 28-V bus 1 from channel A and 28-V BAT bus from channel B. These two power sources are diode isolated, providing short-circuit protection to prevent loss of both 28-V buses in case of a shorted wire or shutoff valve.
What system is brake accumulator
3 hyd acc
How many brake applications
6
Where are brake control valves
Main u/c wheel well
What hyd system is normal brake
Syst 2, and emerg/parking is system 3
Is there any anti skid or protection on emergency
No, system 3 via accumulator and only 6 applications
Does the overheat have a reset
Yes on flight deck near brake panel
When is auto brake set
In flight
What wheels does the emerg brake supply
2 and 3
