The engine defect in the Airbus A350 plane that led to the cancellation of dozens of Cathay Pacific flights in early September could have escalated into "extensive damage", according to a probe released on Thursday by the Air Accident Investigation Authority (AAIA). Cathay briefly grounded its fleet of A350s for inspections and repairs after a Zurich-bound plane was forced to turn back to Hong Kong on September 2. The inspection found that components on 15 of the 48-plane fleet of A350s, powered by engines from the British manufacturer Rolls-Royce, had to be replaced. Investigators said a post-flight examination found a "discernible hole in the (fuel) hose", "black soot observed on the aft section of the core engine, indicating signs of a fire" as well as burn marks. "If not promptly detected and addressed, this situation... could escalate into a more serious engine fire, potentially causing extensive damage to the aircraft," said the AAIA's preliminary report. An AAIA spokesperson said the Preliminary Report had been published to provide factual information established in the investigation's early-evidence collection phase to both the aviation industry and general public in a timely manner, and should be regarded as tentative. "The investigation team is conducting a detailed analysis of the data and information collected in order to determine the circumstances and causes of this occurrence with a view to preventing a recurrence in conjunction with identifying areas for further investigation or lines of inquiry to follow up," the spokesperson said. The AAIA also made a recommendation to the European Union Aviation Safety Agency (EASA) to require Rolls-Royce to "develop continuing airworthiness information, including but not limited to, inspection requirements of the secondary fuel manifold hoses" of the engines in question. Cathay's incident prompted other airlines in Asia to carry out similar checks on their A350-900 and A350-1000 models, which are both powered by Rolls-Royce Trent engines. The EASA also mandated inspections on A350-1000s, of which there are 86 such planes in service worldwide. Qatar Airways is the biggest operator of the 1000 version, with 24 in its fleet, followed by Cathay Pacific and British Airways, which both operate 18. Airbus and Rolls-Royce earlier said they are cooperating with Cathay, but could not comment further pending the investigation. The AAIA, an independent investigation authority formed under the Transport and Logistics Bureau, is responsible for the investigation of civil aircraft accidents and incidents in accordance with the Hong Kong Civil Aviation regulations and with reference to the International Civil Aviation Organisation's standards. (Additional reporting by AFP)
