Hong Kong aviation investigators say an engine problem that caused Cathay Pacific to ground its entire fleet of Airbus A350 jets for inspection earlier this month could have escalated into “extensive damage.”
Cathay canceled dozens of flights in early September, citing the need to inspect its A350 planes after the engine issue forced a Zurich-bound flight to return to Hong Kong shortly after takeoff on September 2.
The airline had previously identified an engine component failure on the affected aircraft, though it stopped short of revealing what the problem was.
On Thursday, Hong Kong’s Air Accident Investigation Authority (AAIA) said it had found “a discernible hole” in the fuel hose, along with black soot “indicating signs of a fire,” during its own inspection.
The AAIA said it was possible for fuel to leak through the ruptured hose, triggering a fire that could spread to surrounding parts of the engine.
“If not promptly detected and addressed, this situation, along with further failures, could escalate into a more serious engine fire, potentially causing extensive damage to the aircraft,” it said.
Burn marks were additionally found under the aircraft’s two reverse thrusts, which redirect exhaust to create a braking effect in order to slow a plane after landing, according to a preliminary report issued by the body.
The AAIA recommended the European Union Aviation Safety Agency to require Rolls-Royce, the engine maker behind the popular A350 long-haul jets, to “develop continuing airworthiness information” on the problem.
Following the incident, Cathay conducted a thorough inspection of its 48-strong A350 fleet and replaced components on 15 of the planes.
The A350 family, which has two models, uses two different Trent XWB turbofan engines from Rolls-Royce.
CNN has reached out to Cathay and Rolls-Royce for comment.