An engine defect in the Airbus A350 plane that led to the cancellation of dozens of Cathay Pacific flights earlier this month could have escalated into "extensive damage", according to the results of a Hong Kong probe released Thursday.
According to AFP, Hong Kong-based Cathay briefly grounded its fleet of A350s for inspections and repairs after a Zurich-bound plane was forced to turn around and head back to the Chinese city on September 2.
The inspections found that components on 15 of the 48 planes in the fleet of A350s, powered by engines from the British manufacturer Rolls-Royce, had to be replaced.
In Thursday's report, the Hong Kong investigators said a post-flight examination of the Zurich-bound plane found that a fuel hose had ruptured, as evidenced by a "discernible hole", burn marks and "black soot observed on the aft section of the core engine".
The fuel could have leaked through the ruptured hose and resulted in a fire that would have spread to surrounding areas, said the report released by the Air Accident Investigation Authority (AAIA).
"If not promptly detected and addressed, this situation... could escalate into a more serious engine fire, potentially causing extensive damage to the aircraft," it said, categorising the incident as "serious".
Five additional fuel hoses in the Zurich-bound plane -- which was manufactured in 2019 -- were also found to have either "frayed metal braids or collapsed structures", the authority said.
To address the issue, the AAIA recommended that the European Union Aviation Safety Agency 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, AFP added.
In its report, Hong Kong investigators said the Cathay flight crew saw an engine fire warning for the number two engine shortly after liftoff. The crew declared an emergency "mayday" signal but later downgraded it to a call indicating an urgent situation. The fire warning was cleared after 59 seconds, as the crew shut down the engine and used a fire extinguisher, AFP further reported. -- AFP