Learn how to arm Airbus A321 autobrake, choose LO, MED or MAX, understand DECEL, manage touchdown and fix common simulator problems.
On a real Airbus A321, select LO or MED on the AUTO BRK panel during approach, verify the mode is armed, and arm the ground spoilers. After main-gear touchdown, spoiler deployment activates autobraking. Use MAX only for take-off rejection, then disarm landing autobrake with gentle pedal pressure or the selected pushbutton.
For Aviation & Real-World Flying, this is standard A320-family logic, although exact indications and operator procedures can vary. Autobrake meters pressure through the normal wheel brakes and anti-skid system to maintain a target deceleration; our explanation of how landing gear, wheel brakes and anti-skid work covers the underlying hardware.
Which Airbus A321 autobrake setting should I use?
Choose the mode from the landing-performance calculation and operating procedure, not from runway condition alone.
| Mode | Purpose | When to select it |
|---|---|---|
| LO (LOW) | Delayed, gentler landing deceleration | Normal landings where runway length and the planned exit permit a longer rollout |
| MED | Earlier, stronger landing deceleration | When performance calculations, runway length, surface condition or operational requirements call for it |
| MAX | Maximum rejected take-off braking | On the ground before take-off as directed by the checklist; it is not a stronger landing mode |
For departure, select MAX on the ground and verify it is armed before take-off. During a high-speed rejected take-off, retarding the thrust levers and deploying the ground spoilers triggers maximum autobraking. Use reverse and complete the remaining actions according to the aircraft or operator procedure; a low-speed rejection may require manual braking.
How do I arm A321 autobrake for landing?
- Calculate the landing: Select LO or MED using the required landing distance, runway state, wind and operator procedure.
- Configure the approach: Complete the slat and flap configuration using the appropriate A321 flap-selection timing. Move the speedbrake lever to the armed position and confirm the ground-spoiler armed indication.
- Select autobrake: Press the LO or MED pushbutton on the AUTO BRK panel. Confirm the blue ON light and any required cockpit display indication. The green DECEL light is not the armed indication.
- Touch down: After main-gear touchdown, place the thrust levers at idle as required. Ground-spoiler deployment activates autobraking; wheel contact by itself is not the trigger.
- Use reverse thrust: Apply reverse as prescribed. Because autobrake targets aircraft deceleration, reverse thrust normally causes the system to demand less wheel-brake pressure. Avoid unintended toe-brake input, which can disengage autobrake.
- Take over smoothly: At the appropriate taxi speed, apply gentle pedal pressure to disarm autobrake and continue with manual braking. Pressing the active autobrake pushbutton again also disarms it. Verify the mode indication extinguishes.
For the flare, touchdown, reverse and braking sequence around these steps, see our complete simulator landing procedure.
What does the DECEL light mean?
The green DECEL light means the aircraft has achieved approximately the demanded deceleration; it does not merely mean that wheel brakes are receiving pressure. The blue ON indication shows that the selected mode is armed.
On a slippery runway, autobrake can be working at the anti-skid limit without reaching its target, so DECEL may remain extinguished. Monitor the speed trend and remaining runway rather than treating that light as proof that braking has failed. Apply manual braking if the stopping performance is inadequate, accepting that pedal input disarms autobrake.
Why does A321 autobrake fail to activate in a simulator?
Most simulated autobrake failures come from spoiler logic, control-axis noise or an aircraft model that implements only part of the real system.
- Ground spoilers did not deploy: Check that the speedbrake lever was armed and that the touchdown and thrust-lever conditions were satisfied. A bounce can retract the spoilers and interrupt or disarm autobraking.
- Toe brakes are not fully released: A noisy or poorly calibrated pedal axis can register brake input and cancel autobrake immediately. Add a small dead zone, recalibrate the pedals and release the parking brake.
- Anti-skid or normal braking is unavailable: Autobrake may refuse to arm or drop out when the required braking system is switched off or has failed.
- The control binding repeats: A button mapped as a continuous command can select and then instantly deselect the mode. In FSX, compare the assignment with the default FSX brake and control bindings.
- The aircraft uses simplified systems: Some default or lower-fidelity A321 models animate the switch without reproducing Airbus activation delays, DECEL logic or automatic disarming. Trust the aircraft-specific checklist and annunciations rather than assuming every A321 add-on behaves identically.