What happened
During the flight, a failure occurred within the number one static inverter, triggered by a malfunctioning C60x series capacitor. This component failure resulted in the inverter failing and the emission of smoke into the flight deck. Due to the necessity of using oxygen masks, communication between the flight crew and the Senior Cabin Crewmember (SCC) became difficult. This lack of clear communication led the SCC to initially misinterpret the situation as an unspecified leak, prompting preparations for a potential depressurisation event.
Despite the initial misunderstanding, the procedures required for managing the smoke event were similar to those for a depressurisation, meaning the cabin management remained effective. During the incident, the SCC found that the required Cabin Preparation cards were inaccessible while seated. However, the crew successfully completed all necessary actions to prepare the cabin for landing and a precautionary disembarkation without needing to reference the cards.
The investigation
Technical examination revealed that the failure of the C60x series capacitor was consistent with known failure patterns observed in other capacitors of the same series. The investigation also focused on the operational challenges faced by the crew, specifically the impact of oxygen mask usage on cockpit-to-cabin communication and the physical accessibility of emergency documentation for seated cabin crew.