Europe's air safety regulator said on Thursday it would call for inspections of at least part of the Airbus A350 long-haul fleet after an engine part failed during the flight of a Cathay Pacific A350-1000 jetliner on Monday.
The European Union Aviation Safety Agency (EASA) said it was acting as a precaution to prevent similar events after consulting Hong Kong regulators and accident investigators, as well as Airbus and engine supplier Rolls-Royce.
It also confirmed that the failure of part of the fuel system had caused a fire that was quickly tackled by the crew.
"We will require a one-time fleet inspection, which may be applicable only to a portion of the A350 fleet, in order to identify and remove from service any potentially compromised high-pressure fuel hoses," EASA said in an emailed statement.
Details and time limits for checks will be outlined in an emergency airworthiness directive on Thursday, it added.
Rolls-Royce and Airbus both said they were working closely with authorities to comply with the directive. Rolls-Royce said it was focused on minimizing any short-term disruption, adding: "We apologize to those who may be affected."
The A350-1000, the larger of two models in the Airbus A350 family, and its Rolls-Royce XWB-97 engines have been under the spotlight since a Zurich-bound jet was forced to return to Hong Kong after the engine problem, later traced to a fuel leak.
Initial investigations have revealed that a flexible pipe feeding a fuel injection nozzle was pierced, sources said on Wednesday, and the Hong Kong-led probe must now determine whether this was the cause or a consequence of the incident.
The A350-1000 represents 15% of the A350 fleet in service.
Details of the EASA measure were still being discussed on Thursday, but people familiar with the matter said it was likely to involve a visual inspection of Trent XWB-97 engines with progressive deadlines — a relatively light maintenance task.
The XWB-84 engine, which powers the more widely used A350-900, was seen as less likely to be included in the checks.
The decision to order precautionary checks of at least part of the fleet comes after manufacturers initially argued against the need for checks of the whole A350 population, sources said.
Barring fresh evidence, manufacturers had been leaning against recommending worldwide checks but the final say is with regulators, sources told Reuters on Wednesday.
Key wording
Due to the highly technical nature of modern aircraft and engines, manufacturers typically perform much of the technical groundwork in preparing regulatory instructions and play a crucial part in global monitoring of the fleet in service.
However, regulators can override their recommendations and order their own checks, and they face increasing pressure to be seen to act independently following a global tightening of safety oversight in the wake of a Boeing safety crisis.
The decision is seen as the first public test for recently appointed EASA Executive Director Florian Guillermet.
Although it was quickly contained and nobody was injured, the stakes in how the incident is handled remain high for Rolls-Royce and airlines amid public concerns over air safety.
Insiders said that could prompt a tug-of-war over technical wording spelling out the criteria for replacing any parts.
Rolls is seen as anxious to ensure any repair work is driven by technical factors rather than less tangible pressure on airlines and is likely to remind carriers to use correct procedures and tools after a wave of ad hoc inspections, sources said.
Airlines, for their part, have been pushing for more clarity from Airbus and the engine maker and have been critical of the lack of communication as they face questions from passengers.
Airbus and Rolls-Royce sought to address airlines' questions on Thursday during their first closed briefings to carriers since Monday's incident. Questions included which planes would be affected and the availability of parts, a person briefed on the matter said.
