# Autobrake

### AUTOBRAKE SELECTOR KNOB (ROTARY ACTION) <a href="#toc118376651" id="toc118376651"></a>

* RTO: Selects Rejected Takeoff deceleration rate. This mode is equivalent to maximum manual braking.
* OFF: Autobrake is deactivated.
* LO: Selects the low deceleration rate.
* MED: Selects the medium deceleration rate.
* HI: Selects the high deceleration rate.

### AUTOBRAKE OPERATION <a href="#toc118376652" id="toc118376652"></a>

* Modulates hydraulic pressure to the brakes in order to provide a constant deceleration rate corresponding to the level selected.
* If reverse thrust is actuated, the autobrake system will modulate the brake pressure to maintain the deceleration rate constant to the mode selected.
* <mark style="color:red;">Anti skid, touchdown and locked wheel protections are provided during autobrake operation.</mark>
* Autobrakes will be disengaged when brake pedal pressure is applied, or the thrust lever is above idle.
* Rejected Takeoff autobrakes will engage when:
  * Thrust levers IDLE or REV.
  * Wheelspeed above 60kts.
  * Brake pedals not pressed.
* Ways to disarm the autobrakes:
  * Selector switch set to OFF.
  * Pedal braking is applied.
  * <mark style="color:red;">Brake control system failure is detected.</mark>
  * Either thrust lever is advanced beyond IDLE during autobrake application.