EASA AD 2021-0103
Navigation — Air Data Reference Inoperative / Master Minimum Equipment List — Amendment
Summary
EASA Airworthiness Directive 2021-0103 is an amendment affecting Airbus A330 and A340 aeroplanes. It addresses a safety issue related to the Air Data Reference (ADR) system and updates the Master Minimum Equipment List (MMEL) for these aircraft models. The directive mandates changes to operational documentation and flight crew procedures to mitigate risks associated with ADR failures.
What Changed
This directive introduces a restriction on the repair interval for the ADR system as specified in the Airbus A330/A340 ATA34 MMEL item 34-10-01. It requires operators to implement the revised MMEL Major Event Revision (MER) that limits dispatch with one ADR inoperative. The change aims to prevent loss of control scenarios caused by multiple ADR failures and erroneous airspeed data.
Why It Matters
The amendment is critical for maintaining safe flight operations by ensuring that aircraft are not dispatched with ADR failures beyond a safe interval. It impacts operators, maintenance organizations, and compliance teams by imposing stricter requirements on dispatch conditions and repair timelines. Adhering to this directive helps prevent potential loss of control incidents related to air data system failures.
What To Do
Operators must update their operational documentation to incorporate the MMEL changes related to ATA34 MMEL item 34-10-01 within 90 days of the directive's effective date. Flight crews must be informed of the new dispatch restrictions and operate the aircraft accordingly. Compliance with the revised MMEL must be maintained to meet regulatory requirements.
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