Paris, January 12 - Airbus has amended its de-icing checklists in response to multiple incidents where the inadvertent failure to deactivate the ditching pushbutton after ground de-icing operations led to cabin pressurization failures and subsequent cabin-altitude alerts. The ditching pushbutton, a guarded control on Airbus narrowbody aircraft such as the A320 family, serves a dual purpose: it prepares the aircraft for emergency water landings by sealing various inlets and valves, and during de-icing, it prevents the ingestion of de-icing fluid into the cabin air system by isolating bleed-air sources and closing relevant openings. When activated on the ground, this configuration is essential for safety during fluid application, but it must be reversed before takeoff to allow normal pressurization.
In several reported events, including a notable case involving an EasyJet A320neo, crews completed de-icing preparations but neglected to deselect the ditching pushbutton during post-de-icing reconfiguration. As the aircraft climbed, the pressurization system remained inhibited, causing the cabin altitude to rise steadily and eventually trigger excess cabin altitude warnings. Pilots responded by initiating emergency descent procedures, identifying the misconfiguration, and resetting the pushbutton, which restored normal pressurization without further incident. Airbus has acknowledged awareness of at least six similar occurrences, highlighting a recurring procedural vulnerability in the transition from de-icing to normal flight configuration.
The manufacturer's response includes targeted revisions to the de-icing checklists, incorporating explicit comments and notes beneath the relevant action lines for the ditching pushbutton. These additions emphasize that leaving the pushbutton engaged after de-icing completion will prevent in-flight pressurization and ultimately activate the cabin-altitude alert. The updates aim to reinforce crew awareness of this critical step, reducing the risk of oversight during high-workload ground operations in cold weather conditions.
This proactive measure underscores Airbus's commitment to continuous safety enhancement in aircraft operations, particularly for procedures involving ground de-icing and cabin pressurization systems. By addressing these configuration errors through clearer guidance, the amendments help mitigate potential disruptions and ensure safer departures in icing environments. Operators are incorporating the revised checklists to align with the latest manufacturer recommendations, further strengthening overall flight safety protocols.