Cathay Pacific's Airbus A350 engine defect that led to multiple flight cancellations in early September could have resulted in "extensive damage", according to a report released on Thursday by the Hong Kong Air Accident Investigation Authority (AAIA).

The issue came to light after a Zurich-bound Cathay Pacific flight was forced to return to Hong Kong on 2 September. Following this incident, the airline briefly grounded its fleet of A350s for inspections and repairs.

The inspection revealed that components on 15 of Cathay's 48 A350s, which are powered by Rolls-Royce engines, needed replacement. Investigators discovered a "discernible hole in the (fuel) hose", burn marks, and "black soot" indicating fire in the core engine's aft section.

"If not promptly detected and addressed, this situation ... could escalate into a more serious engine fire, potentially causing extensive damage to the aircraft," the report warned.

The AAIA's preliminary findings were described as "tentative" by a spokesperson, who also recommended that the European Union Aviation Safety Agency (EASA) require Rolls-Royce to develop airworthiness information, including inspection requirements for the affected engines' secondary fuel manifold hoses.

Cathay Pacific's incident spurred other airlines in Asia to conduct similar inspections on their A350-900 and A350-1000 models, which are powered by Rolls-Royce Trent XWB-84 and XWB-97 engines. The EASA has also mandated inspections on A350-1000 aircraft worldwide, with 86 such planes in service.

Qatar Airways operates the largest fleet of A350-1000s with 24 planes, followed by Cathay Pacific and British Airways, each with 18.

Both Airbus and Rolls-Royce confirmed their cooperation with Cathay Pacific but declined to comment further due to the ongoing investigation.

Source: AFP