What steps are taken when an ECAM displays UNRELIABLE SPEED?

• A. Disengage autothrust and autopilot, manually manage speed with pitch/thrust, verify data, and follow ECAM/alternate procedures.
• B. Increase thrust to maximum and ignore ECAM.
• C. Engage autopilot and adjust speed to fit target.
• D. Reboot ECAM system, then continue.

Answer: (A)

When ECAM shows UNRELIABLE SPEED, the airspeed data you’re receiving cannot be trusted. Relying on automatic speed control with bad data can drive the airplane toward dangerous regimes, so the pilot must take manual control to ensure safe handling.

The proper response is to disengage autothrust and autopilot, then manually manage airspeed with pitch and thrust. By removing automatic speed authority, you prevent the flight control system from acting on faulty information and you can stabilize the aircraft using your own judgment of pitch attitude and thrust setting. While doing this, verify the speed indication with the standby instruments and follow the ECAM’s alternate procedures to diagnose the fault or switch to an alternate air data source. Continue to monitor and adjust until reliable data is restored or the ECAM sequence directs a safe reconfiguration, keeping within safe speed margins and stall protection.

Other options don’t address the underlying issue. Ignoring the ECAM or forcing maximum thrust can compound the problem or lead to unsafe conditions, and rebooting the ECAM doesn’t fix the faulty air data.