On 1 December 2024, Air New Zealand flight NZ249, an A320neo operating Wellington–Sydney, experienced an uncommanded engine shutdown about 40 minutes after departure. The crew declared a Mayday and diverted safely to Auckland for a single‑engine landing.

The New Zealand TAIC investigation confirmed the shutdown was caused by the engine fire pushbutton on the overhead panel releasing by itself – not by pilot action. A retaining pin inside the switch had been bent before installation due to supplier mishandling. Because the pin couldn’t hold the switch fully latched, normal in‑flight vibration allowed it to pop out, which automatically shut down the engine. Both pilots independently confirmed they had not touched the switch and the checklists at the time did not require verifying the fire panel position after a shutdown.

In 2026, an A350 flying LAS – LHR experienced a similar event: an unexpected engine rundown at night near Halifax after the No.2 engine fire switch popped out, triggering multiple ECAM alerts. With the captain resting, the PF initiated a descent and declared PAN while stabilising the aircraft. ECAM messages were brief and did not initially indicate an engine failure, but the engine SD page confirmed loss of thrust. After the captain returned, the crew attempted an in‑flight relight, which was not possible until the fire switch was pushed back in following advice from Maintrol. The relight succeeded, systems stabilised, and the crew elected to continue to Heathrow, landing normally.

Why this is easy to miss: Airbus fire switches sit high on the overhead panel, recessed and guarded, and are not part of the normal scan unless a fire warning is active. When they release mechanically, the visual cue is subtle – especially at night – although you might hear a click as it releases. This makes a popped fire switch surprisingly easy to overlook. Both events underline the value of a deliberate overhead check whenever fuel valve or generator related ECAMs appear unexpectedly.

The same fire panel design is used across the A320 family, and similar systems appear on larger Airbus types. Safran issued service bulletins in late 2024, Airbus followed with inspection instructions in December 2024, and EASA AD 2025‑0274 now mandates inspection and replacement of affected switches across the global fleet by November 2027.

How serious is this failure mode? Depending on when it happens, it could be:

• Challenging in cruise
• Potentially hazardous in initial climb, especially with terrain or SID constraints
• Critical at V1

Risk picture

• Likelihood: Low
• Severity: High to potentially catastrophic depending on phase of flight, especially if the problem is misidentified
• Overall risk: Medium/High until the suspect switches are replaced fleet‑wide

Advice:

• Keep fire indication discipline tight: confirm & cross‑check before action
• Include false fire handle/pushbutton events in simulator profiles
• Reinforce the Airbus golden rules: Aviate, Navigate, Communicate… then ECAM

Bottom line

This is a serious mechanical defect, and it’s completely latent – no ECAM cue until the moment it happens. So far, outcomes have relied on solid crew handling, but the long compliance window understandably feels uncomfortable. Until the hardware is replaced, awareness and disciplined SOPs remain our best mitigation.

BALPA will continue to monitor regulatory progress on AD 2025-0274 and urges members operating affected Airbus types to familiarise themselves with the service bulletin details and raise any concerns with their operators without delay.

BALPA’s Accident Analysis and Prevention (AAP) Group reviews safety occurrences to provide members with timely, practical guidance. If you have information relevant to this or similar events, contact the safety team directly. With more than half a million people flying in UK airspace each day, the work of the Accident Analysis and Prevention group is a cornerstone of BALPA’s mission: to protect pilots and ensure that the UK remains one of the safest aviation environments in the world. If you would like to get involved in the work of the AAP, email aap@balpa.org