EASA AD 2025-0271
Central Maintenance System — Central Computer / Primus APEX Operational Software — Modification
Summary
EASA Airworthiness Directive 2025-0271 is an official regulatory document addressing Pilatus PC-12/47E aeroplanes with specific serial numbers. It mandates modifications to the Central Maintenance System's Primus APEX Operational Software to enhance flight safety. The directive applies specifically to PC-12/47E aircraft equipped with certain software builds.
What Changed
This directive introduces a mandatory update to the Primus APEX Operational Software from build 12.7.1 or earlier to build 12.7.2. It also requires implementation of a Temporary Revision to the Pilot’s Operating Handbook and prohibits installation of the affected older software versions. These changes address a safety issue related to the Stall Warning Protection System triggering at inappropriate airspeeds.
Why It Matters
The update is critical for maintaining safe flight operations by preventing premature stall warnings that could increase pilot workload and reduce aircraft control. Operators and maintenance organizations must comply to ensure continued airworthiness and avoid operational restrictions. Compliance also ensures alignment with EASA regulations and helps mitigate potential safety risks during specific flight conditions.
What To Do
Operators of affected PC-12/47E aeroplanes must upload the updated Primus APEX Operational Software build 12.7.2 within 12 months of 16 December 2025. They must also implement the Pilot’s Operating Handbook Temporary Revision either before the next flight after software update or within 30 days of the directive’s effective date, depending on the aircraft group. Installation of older software versions is prohibited from the effective date onward.