If ADS data disagrees with other sources, the recommended action is to

• A. Fly with standby instruments as primary and verify with alternate sources.
• B. Continue with the primary ADS and ignore discrepancy.
• C. Request diversion to nearest airport.
• D. Turn off the Autopilot and rely on manual flight.

Answer: (A)

When the air data system (ADS) readings conflict with other sources, the priority is to ensure you’re flying with reliable references. The standby instruments are designed to be independent from the primary air data path, so using them as the primary reference keeps you in control even when the ADS is faulty or producing questionable data.

Relying on the standby instruments provides you with essential flight indications—airspeed, attitude, and altitude—without depending on the suspected faulty ADS. At the same time, you should verify these indications against alternate sources within the aircraft, such as remaining air data or navigation sensors, to determine which source is correct and to confirm stable flight parameters.

This approach preserves safety by maintaining accurate flight references, rather than continuing with potentially erroneous ADS data or reacting inappropriately to a fault.