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EASA regulator orders checks on some A350 jets

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Measure involves visual checks of A350-1000 engines

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Comes after engine part failed on Cathay Pacific jet

(Recasts after regulator issues safety bulletin)

By Joanna Plucinska and Tim Hepher

LONDON/PARIS, Sept 5 (Reuters) - Europe's air safety

regulator on Thursday ordered inspections on engines of Airbus

A350-1000 jets after an engine fire during the flight

of a Cathay Pacific jetliner.

The European Union Aviation Safety Agency (EASA) said it was

acting to prevent similar events after consulting regulators and

accident investigators in Hong Kong, where Cathay is based, as

well as Airbus and engine supplier Rolls-Royce.

"This action is a precautionary measure, based on the

information received from the initial investigation of the

recent Cathay Pacific serious incident and on the airline's

findings in its own subsequent inspections," EASA Executive

Director Florian Guillermet said in a statement.

EASA also confirmed that the failure of a hose in the fuel

system had caused a fire that was quickly tackled by crew.

A "serious incident" is an investigative term in aviation

that means there was a high probability of an accident.

"We will continue to follow closely all information that

will be made available through the ongoing safety

investigation," Guillermet said.

The move affects the larger of two models of twin-engined

A350, the A350-1000, which represents 15% of the A350 fleet or

86 jets. The smaller and widely sold A350-900 is not affected.

In an emergency directive issued late on Thursday, EASA gave

airlines between three and 30 days to carry out visual checks

and measurements on the fuel hoses but did not call for parts to

be removed for the work, unless they were found to be damaged.

It excluded engines already inspected by Cathay.

Rolls-Royce and Airbus said earlier they were working

closely with authorities to comply with the planned directive.

Rolls said it was focused on minimising any short-term

disruption, adding: "We apologise to those who may be affected".

The A350-1000 and its XWB-97 engines have been under the

spotlight since a Zurich-bound jet was forced to return to Hong

Kong on Monday after the engine problem, later traced to a fuel

leak.

Initial investigations have revealed that a hose between a

manifold and 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.

EASA said the fire had caused heat damage to the engine

housing, including ducts used for reverse-thrust on landing.

"This condition, if not detected and corrected could, in

combination with additional failures, lead to a more severe

engine fire and resulting damage to an aeroplane," it said.

Reuters had reported earlier on Thursday that the EASA's

measure was likely to involve a visual inspection with

progressive deadlines - a relatively light maintenance task.

By ordering checks, however, EASA partially overrode

efforts by manufacturers to avoid disruptive action on the whole

fleet on the basis of their own technical analysis, sources

said.

Barring fresh evidence, they had been leaning against

recommending worldwide checks but the final say is with

regulators, sources told Reuters on Wednesday.

PUBLIC TEST

Due to the highly complex nature of 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 ( BA ) safety crisis.

Thursday's 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.

The directive followed hours of talks over key technical

wording spelling out the criteria for replacing any parts.

Rolls is seen 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 clarity from

Rolls and Airbus and some have been privately critical of the

lack of communication as they face questions from passengers.

Airbus and Rolls sought to address airlines' questions on

Thursday during their first closed briefings since Monday's

incident. Questions included which planes would be affected and

the availability of parts, a person briefed on the matter said.