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Brakes
Also from: Autobrake
The main wheels have carbon brakes actuated by either the normal or alternate brake system. The normal system uses green hydraulic pressure, the alternate system and parking brake uses blue, backed up by the hydraulic accumulator.
Maintenance is required when the temperature difference between 2 brakes of the same gear > 150° or when the temperature of one brake > 600° or < 60°.
Accumulator
The accumulator brake pressure is checked with the parking brake off. An indication in the green means the accumulator can hold parking brake pressure for 12 hours. It allows about 7 brake applications if autobraking is not working. The blue hydraulic electrical pump can be used to recharge the accumulator.
Autobrake
When the landing gear lever is in the up position, the autobrake is automatically disengaged. After landing, extension of the ground spoilers triggers the autobrake (after 1s if LO is used). The DECEL light on the AUTO/BRK pbs illuminates when deceleration is at least 80% of the selected rate. Note that for a reject below 72 kt, the autobrake will not activate as the spoilers do not extend.
The autobrake is disarmed when the spoilers are retracted, or by applying pressure to one brake pedal.
Autobrake MAX is only used for takeoff.
Modes
| Antiskid | Autobrake | Hydraulic System | Notes | |
| Normal |  | | green | |
| Alternate with Antiskid | |  | blue | active in flight with gear up (pressure applied to the brake pedals in-flight will be indicated on the triple indicator) |
| Alternate w/o Antiskid | | | blue or accumulator | may also be electrical failure (including BSCU), modulate brake pressure to 1,000 psi |
| Parking Brake | - | - | blue | or uses accumulators (at least 7 full brake applications) |
Parking brake
The park brake is electrically controlled and works when airborne. It has priority over normal and alternate braking. To check the brake wear indicators, the parking brake should be on. If the parking brake fails, the PARK BRK handle should be released to restore braking to the pedals.
Failures
| BRAKES HOT | - 1 brake temperature is > 300°C |
| BRAKES RELEASED | - tachometer has failed or brake servo valve is jammed closed |