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Then there is an abnormal attitude law. This law activates if the aircraft gets into a position where computers can no longer keep it in the envelope. Keep in mind that even though the aircraft is protected, in very tight situations things can go beyond the protections. In this case also the protections are turned off and alternate law activated which allows pilot to maneuver out of the situation. The abnormal attitude law activates if any of the following conditions are met:

• Bank angle above 125 °
• Pitch attitude above 50 ° nose up or below 30 ° nose down
• Speed below 60 to 90 kt (depending on the aircraft pitch attitude), or above 440 kt
• Mach above 0.91
• Angle of attack above 30 ° to 40 °, or below -10 °

Then there is an abnormal attitude law. This law activates if the aircraft gets into a position where computers can no longer keep it in the envelope. Keep in mind that even though the aircraft is protected, in very tight situations things can go beyond the protections. In this case also the protections are turned off and alternate law activated which allows pilot to maneuver out of the situation. For the A320 the abnormal attitude law activates if any of the following conditions are met:

• Bank angle above 125 °
• Pitch attitude above 50 ° nose up or below 30 ° nose down
• Speed below 60 to 90 kt (depending on the aircraft pitch attitude), or above 440 kt
• Mach above 0.91
• Angle of attack above 30 ° to 40 °, or below -10 °

So, can the Airbus protections be turned off? Simple answer is, Yes. If required it can be manually turned off and the aircraft control laws degraded from normal law to alternate law.

So, can the Airbus protections be turned off? The simple answer is, Yes. If required it can be manually turned off and the aircraft control laws degraded from normal law to alternate law.

The switching off ADRs cannot be found in the aircraft FCOM or the FCTM. It is little secret all Airbus pilots are aware of. When I did my type rating on the aircraft, I learnt it when our instructor shut them off to practice stalls. Airbus however, mentioned the procedure in the Airbus initial type training course guide. There was a time though when Airbus had the procedure as a temporary OEB (Operational engineering bulleting) after a Lufthansa A321 suffered a spurious high angle of attack protection activation due to two faulty AOA sensors. The pilots were only able to control the aircraft by forcing it into alternate law by switching off ADR 2 and ADR 3 which was already rejected by the computers. The OEB Airbus released, numbered OEB 48, was there in the aircraft QRH until they got new angle of attack sensor modifications.

The switching off ADRs cannot be found in the aircraft FCOM or the FCTM. Nevertheless, it is little secret all Airbus pilots are aware of. When I did my type rating on the aircraft, I learnt it when our instructor shut them off to practice stalls. Airbus however, mentioned the procedure in the Airbus initial type training course guide. There was a time though when Airbus had the procedure as a temporary OEB (Operational engineering bulleting) after a Lufthansa A321 suffered a spurious high angle of attack protection activation due to two faulty AOA sensors. The pilots were only able to control the aircraft by forcing it into alternate law by switching off ADR 2 and ADR 3 which was already rejected by the computers. The OEB Airbus released, numbered OEB 48, was there in the aircraft QRH until they got new angle of attack sensor modifications.