EASA Mandates Urgent Software and Hardware Fixes for Airbus A320 Fleet After Solar Flare

Global space weather monitoring confirmed a pronounced escalation in solar activity as of November 29, 2025, following a period of relative quietude in the preceding weeks. This heightened state is directly attributable to the emergence of an intensely active sunspot cluster designated AR4294 as it rotated into the Earth-facing hemisphere. The region has proven highly energetic, producing a total of three M-class flares within the preceding 24-hour period, including a significant M5.9 event recorded at 22:22 UTC on November 28.

This specific M5.9 flare was powerful enough to induce an R2-level moderate radio blackout that affected communications across the vast expanse of the Pacific Ocean. These immediate terrestrial consequences of the solar surge prompted swift regulatory action within the aviation sector. The European Union Aviation Safety Agency (EASA) acted decisively on November 28, issuing an Emergency Airworthiness Directive (EAD) that became effective on November 29 at 23:59 UTC.

The directive mandates immediate software and hardware remediation for an estimated 6,000 Airbus A320 family aircraft, encompassing the A319, A320, and A321 models in both CEO and NEO configurations. The core concern stems from the vulnerability of the flight-control architecture to data corruption induced by intense solar radiation, a risk highlighted by a recent in-flight incident involving an A320 experiencing an uncommanded and limited pitch down.

Airbus, the manufacturer, had proactively alerted operators via an Alert Operators Transmission (AOT) before the EASA formalized the mandate, acknowledging that a significant portion of the in-service fleet could be susceptible to this radiation interference pathway. The EAD specifically requires the replacement of certain Elevator Aileron Computers (ELAC), identified as the ELAC B L104 units, before the aircraft can undertake subsequent commercial flights. EASA stipulated that only limited, non-ETOPS ferry flights, restricted to three cycles and carrying no passengers, are permissible for positioning aircraft to maintenance facilities for the required service.

The manufacturer noted that the mitigation involves implementing software protections and hardware safeguards to prevent radiation-related corruption of critical flight-control data, with some operators, like American Airlines operating approximately 340 A320s, beginning modifications immediately. This event underscores the increasing operational challenges posed by the current solar maximum phase of Solar Cycle 25, which is leading to more frequent and intense solar phenomena.

For context, this surge follows earlier intense activity in November 2025, where an X5.1-class flare from region AR4274 on November 11 triggered severe geomagnetic storms (G4) and widespread radio blackouts across Africa and Europe. While the current M-class flares from AR4294 are less severe than the X-class events earlier in the month, their ability to cause localized radio blackouts demonstrates the ongoing need for vigilance in monitoring space weather impacts on critical, high-technology systems like modern avionics. The aviation industry is now navigating a landscape where space weather is a direct, immediate factor in airworthiness compliance and operational scheduling.